Current status of liver transplantation for human immunodeficiency virus-infected patients in mainland China

According to the report from the Chinese Center for Disease Control and Prevention, the prevalence of human immunodeficiency virus (HIV) infection exceeded 1.2 million individuals by the year 2022, with an annual increase of about 80000 cases. The overall prevalence of hepatitis B surface antigen among individuals co-infected with HIV reached 13.7%, almost twice the rate of the general population in China. In addition to the well-documented susceptibility to opportunistic infections and new malignancies, HIV infected patients frequently experience liver-related organ damage, with the liver and kidneys being the most commonly affected. This often leads to the development of end-stage liver and kidney diseases. Therefore, organ transplantation has emerged as an important part of active treatment for HIV infected patients. However, the curative effect is not satisfactory. HIV infection has been considered a contraindication for organ transplantation. Until the emergence of highly active anti-retroviral therapy in 1996, the once intractable replication of retrovirus was effectively inhibited. With prolonged survival, the failure of important organs has become the main cause of death among HIV patients. Therefore, transplant centers worldwide have resumed exploration of organ transplantation for HIV-infected individuals and reached a positive conclusion. This study provides an overview of the current landscape of HIV-positive patients receiving liver transplantation (LT) in mainland China. To date, our transplant center has conducted LT for eight end-stage liver disease patients co-infected with HIV, and all but one, who died two months postoperatively due to sepsis and progressive multi-organ failure, have survived. Comparative analysis with hepatitis B virus-infected patients during the same period revealed no statistically significant differences in acute rejection reactions, cytomegalovirus infection, bacteremia, pulmonary infections, acute kidney injury, new-onset cancers, or vascular and biliary complications.

Extended Conjugation Strategy Enabling Red-Shifted and Efficient Emission of Orange-Red Thermally Activated Delayed Fluorescence Materials

In account of the energy gap law, the development of efficient narrow-band gap thermally activated delayed fluorescence (TADF) materials remains a major challenge for the application of organic light-emitting diodes (OLEDs). The orange-red TADF materials are commonly designed with either large π-conjugated systems or strong intramolecular donor-acceptor (D-A) interactions for red-shift emission and small singlet-triplet energy gap (ΔEST). There are rare reports on the simultaneous incorporation of these two strategies on the same material systems. Herein, two orange-red emitters named 1P2D-BP and 2P2D-DQ have been designed by extending the conjugation degree of the center acceptor DQ and increasing the number distribution of the peripheral donor PXZ units, respectively. The emission peak of 1P2D-BP is red-shifted to 615 nm compared to 580 nm for 2P2D-DQ, revealing the pronounced effect of the conjugation extension on the emission band gap. In addition, the distorted molecular structure yields a small ΔEST of 0.02 eV, favoring the acquisition of a high exciton utilization through an efficient reverse intersystem crossing process. As a result, orange-red OLEDs with both 1P2D-BP and 2P2D-DQ have achieved an external quantum efficiency (EQE) of more than 17%. In addition, the efficient white OLED based on 1P2D-BP is realized through precise exciton assignment and energy transport modulation, showing an EQE of 23.6% and a color rendering index of 82. The present work provides an important reference for the design of high-efficiency narrow-band gap materials in the field of solid-state lighting.

Comprehensive Crystal Regulation Reduces Interfacial Energy Loss for Efficient Blue Perovskite Light-Emitting Diodes

As an essential component of future full-color displays, blue perovskite light-emitting diodes (PeLEDs) still lag far behind the red and green counterparts in the device performances. In the mainstream quasi-2D blue perovskite system, trap-mediated nonradiative loss, low energy transfer efficiency, and interface fluorescence quenching remain significant challenges. Herein, guanidinium thiocyanate (GASCN) and potassium cinnamate (PCA) are respectively introduced into the hole transport layer (HTL) and the perovskite precursor to achieve a dense and uniform perovskite thin film with greatly improved optoelectronic properties. Therefore, adequate GA+ acts as pre-nucleation sites on the HTL surface, regulating crystallization through strong hydrogen bonding with perovskite intermediates. The realized polydisperse domain distribution is conducive to cascade energy transfer, and the improved hole transport ability alleviates interface fluorescence quenching. In addition, the SCN- and CA- groups can form coordination bonds with the defects at the buried perovskite interface and grain boundaries, respectively, which effectively suppresses the detrimental nonradiative recombination. Benefitting from the comprehensive crystal regulation, blue PeLEDs featuring stable emission at 484 and 468 nm exhibit improved external quantum efficiencies of 11.5% and 4.3%, respectively.

Regulating Perovskite Crystallization through Interfacial Engineering Using a Zwitterionic Additive Potassium Sulfamate for Efficient Pure-Blue Light-Emitting Diodes

Quasi-two-dimensional (quasi-2D) perovskites are emerging as efficient emitters in blue perovskite light-emitting diodes (PeLEDs), while the imbalanced crystallization of the halide-mixed system limits further improvements in device performance. The rapid crystallization caused by Cl doping produces massive defects at the interface, leading to aggravated non-radiative recombination. Meanwhile, unmanageable perovskite crystallization is prone to facilitate the formation of nonuniform low-dimensional phases, which results in energy loss during the exciton transfer process. Here, we propose a multifunctional interface engineering for nucleation and phase regulation by incorporating the zwitterionic additive potassium sulfamate into the hole transport layer. By using potassium ions (K+ ) as heterogeneous nucleation seeds, finely controlled growth of interfacial K+ -guided grains is achieved. The sulfamate ions can simultaneously regulate the phase distribution and passivate defects through coordination interactions with undercoordinated lead atoms. Consequently, such synergistic effect constructs quasi-2D blue perovskite films with smooth energy landscape and reduced trap states, leading to pure-blue PeLEDs with a maximum external quantum efficiency (EQE) of 17.32 %, spectrally stable emission at 478 nm and the prolonged operational lifetime. This work provides a unique guide to comprehensively regulate the halide-mixed blue perovskite crystallization by manipulating the characteristics of grain-growth substrate.

Top-Down Exfoliation Process Constructing 2D/3D Heterojunction toward Ultrapure Blue Perovskite Light-Emitting Diodes

3D perovskites with low energy disorder and high ambipolar charge mobility represent a promising solution for efficient and bright light-emitting diodes. However, the challenges of regulating the nanocrystal size to trigger the quantum confinement effect and control the surface trap states to reduce charge loss hinder the applications of 3D perovskites in blue perovskite light-emitting diodes (PeLEDs). In this study, we present a top-down exfoliation method to obtain blue 3D perovskite films with clipped nanocrystals and tunable bandgaps by employing methyl cyanide (MeCN) for post-treatment. In this method, the MeCN solvent exfoliates the surface components of the 3D perovskite grains through a partial dissolution process. Moreover, the dissolved precursor can be further utilized to construct an ingenious 2D/3D heterostructure by incorporating an organic spacer into the MeCN solvent, contributing to efficient defect passivation and improved energy transfer. Consequently, efficient PeLEDs featuring ultrapure blue emission at 478 nm achieve a record external quantum efficiency of 12.3% among their 3D counterparts. This work emphasizes the significance of inducing the quantum confinement effect in 3D perovskites for efficient blue PeLEDs and provides a viable scheme for the in situ regulation of perovskite crystals.

Synchronous Regulation Strategy of Pyrrolidinium Thiocyanate Enables Efficient Perovskite Solar Cells and Self-Powered Photodetectors

Developing inventive approaches to control crystallization and suppress trap defects in perovskite films is crucial for achieving efficient perovskite photovoltaics. Here, a synchronous regulation strategy is developed that involves the infusion of a zwitterionic ionic liquid additive, pyrrolidinium thiocyanate (PySCN), into the perovskite precursor to optimize the subsequent crystallization and defects. PySCN modification not only orchestrates the crystallization process but also deftly addresses trap defects in perovskite films. Within this, SCN- compensates for positively charged defects, while Py+ plays the role of passivating negatively charged defects. Based on the vacuum flash evaporation without anti-solvent, the air-processed perovskite solar cells (PSCs) with PySCN modification can achieve an extraordinary champion efficiency of 22.46% (0.1 cm2 ) and 21.15% (1.0 cm2 ) with exceptional stability surpassing 1200 h. Further, the self-powered photodetector goes above and beyond, showcasing an ultra-low dark current of 2.13 × 10-10 A·cm-2 , a specific detection rate of 6.12 × 1013  Jones, and an expansive linear dynamic range reaching an astonishing 122.49 dB. PySCN modification not only signifies high efficiency but also ushers in a new era for crystallization regulation, promising a transformative impact on the optoelectronic performance of perovskite-based devices.

Rational Multidimensional Shielded Multiple Resonance Emitter Suppresses Concentration Quenching and Spectral Broadening for Solution-Processed Organic Light-Emitting Diodes

Thermally activated delayed fluorescence (TADF) emitters based on multiple resonance (MR) effects are promising for high-definition organic light-emitting diodes (OLEDs) with narrowband emission and high efficiency. However, they still face the challenges of aggregation-caused quenching (ACQ) and spectral broadening. Solution-processable MR-TADF emitters with an external quantum efficiency (EQE) of >20% and a full width at half-maximum (fwhm) of <30 nm have rarely been reported. To construct ACQ-resistant emitters without sacrificing color purity, the aggregation-induced MR-TADF material 6TBN with a rigid B,N-containing polycyclic aromatic hydrocarbon core and four carbazole substituents as well as 12 tert-butyl groups on the periphery is designed. The multidimensional shielded effect largely limits the ACQ, intermolecular interactions, and spectral broadening. Consequently, solution-processed OLEDs based on 6TBN exhibit a maximum EQE of 23.0% and high color purity with a fwhm of 25 nm. Furthermore, the nondoped device achieves a high efficiency (12.3%) and merely a slight widening of the fwhm to 27 nm. This work provides a feasible strategy to achieve MR-TADF materials with resistance to concentration quenching and high color purity.

Hyperbolic polaritonic crystals with configurable low-symmetry Bloch modes

Photonic crystals (PhCs) are a kind of artificial structures that can mold the flow of light at will. Polaritonic crystals (PoCs) made from polaritonic media offer a promising route to controlling nano-light at the subwavelength scale. Conventional bulk PhCs and recent van der Waals PoCs mainly show highly symmetric excitation of Bloch modes that closely rely on lattice orders. Here, we experimentally demonstrate a type of hyperbolic PoCs with configurable and low-symmetry deep-subwavelength Bloch modes that are robust against lattice rearrangement in certain directions. This is achieved by periodically perforating a natural crystal α-MoO₃ that hosts in-plane hyperbolic phonon polaritons. The mode excitation and symmetry are controlled by the momentum matching between reciprocal lattice vectors and hyperbolic dispersions. We show that the Bloch modes and Bragg resonances of hyperbolic PoCs can be tuned through lattice scales and orientations while exhibiting robust properties immune to lattice rearrangement in the hyperbolic forbidden directions. Our findings provide insights into the physics of hyperbolic PoCs and expand the categories of PhCs, with potential applications in waveguiding, energy transfer, biosensing and quantum nano-optics.

Managing Interfacial Defects and Carriers by Synergistic Modulation of Functional Groups and Spatial Conformation for High-Performance Perovskite Photovoltaics Based on Vacuum Flash Method

Interfacial nonradiative recombination loss is a huge barrier to advance the photovoltaic performance. Here, one effective interfacial defect and carrier dynamics management strategy by synergistic modulation of functional groups and spatial conformation of ammonium salt molecules is proposed. The surface treatment with 3-ammonium propionic acid iodide (3-APAI) does not form 2D perovskite passivation layer while the propylammonium ions and 5-aminopentanoic acid hydroiodide post-treatment lead to the formation of 2D perovskite passivation layers. Due to appropriate alkyl chain length, theoretical and experimental results manifest that COOH and NH₃ ⁺ groups in 3-APAI molecules can form coordination bonding with undercoordinated Pb²⁺ and ionic bonding and hydrogen bonding with octahedron PbI₆ ^4- , respectively, which makes both groups be simultaneously firmly anchored on the surface of perovskite films. This will strengthen defect passivation effect and improve interfacial carrier transport and transfer. The synergistic effect of functional groups and spatial conformation confers 3-APAI better defect passivation effect than 2D perovskite layers. The 3-APAI-modified device based on vacuum flash technology achieves an alluring peak efficiency of 24.72% (certified 23.68%), which is among highly efficient devices fabricated without antisolvents. Furthermore, the encapsulated 3-APAI-modified device degrades by less than 4% after 1400 h of continuous one sun illumination.

Suppressed Voltage Deficit and Degradation of Perovskite Solar Cells by Regulating the Mineralization of Lead Iodide

Both the uncoordinated Pb²⁺ and excess PbI₂ in perovskite film will create defects and perturb carrier collection, thus leading to the open-circuit voltage (V_OC ) loss and inducing rapid performance degradation of perovskite solar cells (PSCs). Herein, an additive of 3-aminothiophene-2-carboxamide (3-AzTca) that contains amide and amino and features a large molecular size is introduced to improve the quality of perovskite film. The interplay of size effect and adequate bonding strength between 3-AzTca and uncoordinated Pb²⁺ regulates the mineralization of PbI₂ and generates low-dimensional PbI₂ phase, thereby boosting the crystallization of perovskite. The decreased defect states result in suppressed nonradiative recombination and reduced V_OC loss. The power conversion efficiency (PCE) of modified PSC is improved to 22.79% with a high V_OC of 1.22 V. Moreover, the decomposition of PbI₂ and perovskite films is also retarded, yielding enhanced device stability. This study provides an effective method to minimize the concentration of uncoordinated Pb²⁺ and improve the PCE and stability of PSCs.

[Opportunities and challenges for the high-quality development of hernia and abdominal wall surgery in China]

Hernia and abdominal wall surgery is a relatively new subspecialty in surgery. Although it started late in China, after 25 years of rapid development, it has made remarkable achievements and has become an important part of surgery, laying a solid foundation for the further development of the discipline. At the same time, one should also be soberly aware of the present deficiencies in this field. The development of the field should be more detailed and in-depth from the following aspects: correct understanding of new concepts of hernia and abdominal wall surgery, establishment of hernia patient registration and quality control system, technological innovation and development of technical equipment, especially the expansion of robot surgical systems, materials science progression to hernia and abdominal wall surgery. Faced with this challenge, China is expected to achieve high-quality development in the field of hernia and abdominal surgery.

[Influencing factors of small intestinal ischemia in elderly patients with incarcerated hernia]

Objective: To investigate the factors influencing small intestinal ischemia in elderly patients with incarcerated hernia. Methods: The clinical data of 105 elderly patients admitted for surgical procedures of incarcerated hernia at Department of General Surgery, Huadong Hospital between January 2014 and December 2021 were retrospectively analyzed. There were 60 males and 45 females, aged (86.1±4.3) years (range: 80 to 96 years). They were divided into normal group (n=55) and ischemic group (n=50) according to intraoperative intestinal canal condition. The t test, χ² test and Fisher's exact probability method were used for the univariate analysis of the factors that influence intestinal ischemia in patients, and Logistic regression was used for multifactorial analysis. Results: In all patients, 18 patients (17.1%) had irreversible intestinal ischemia with bowel resection. Six patients died within 30 days, 3 cases from severe abdominal infection, 2 cases from postoperative exacerbation of underlying cardiac disease, and 1 case from respiratory failure due to severe pulmonary infection. The results of the univariate analysis showed that there were differences in gender, history of intussusception, duration of previous hernia, white blood cell count, neutrophil percentage, C-reactive protein, type of incarcerated hernia, and preoperative intestinal obstruction between the two groups (all P<0.05). The Logistic regression results showed that the short time to the previous hernia (OR=0.892, 95%CI 0.872 to 0.962, P=0.003), high C-reactive protein (OR=1.022, 95%CI 1.007 to 1.037, P=0.003), non-indirect incarcerated hernia (OR=10.571, 95%CI 3.711 to 30.114, P<0.01) and preoperative intestinal obstruction (OR=6.438, 95%CI 1.762 to 23.522, P=0.005) were independent risk factors for the development of intestinal ischemia in elderly patients with incarcerated hernia. Conclusions: The short duration of the previous hernia, the high values of C-reactive proteins, the non-indirect incarcerated hernia, and the preoperative bowel obstruction are influencing factors for bowel ischemia in elderly patients with incarcerated hernia. A timely operation is necessary to reduce the incidence of intestinal necrosis and improve the prognosis.

Outcomes of ABO-incompatible liver transplantation in end-stage liver disease patients co-infected with hepatitis B and human immunodeficiency virus

BACKGROUND

Human immunodeficiency virus (HIV)-positive patients coinfected with hepatitis B virus (HBV) are eligible for liver transplantation (LT) in Africa and Southeast Asia, particularly China. However, the outcome of HIV-HBV coinfected patients referred for ABO-incompatible LT (ABOi-LT) is unknown.

AIM

To clarify the outcome of ABOi-LT for HIV-HBV coinfected patients with end-stage liver disease (ESLD).

METHODS

We report on two Chinese HIV-HBV coinfected patients with ESLD who underwent A to O brain-dead donor LT and reviewed the literature on HIV-HBV coinfected patients treated with ABO-compatible LT. The pretransplantation HIV viral load was undetectable, with no active opportunistic infections. Induction therapy consisted of two sessions of plasmapheresis and a single dose of rituximab in two split doses, followed by an intraoperative regimen of intravenous immunoglobulin, methylprednisolone, and basiliximab. Post-transplant maintenance immunosuppressive agents consisted of tacrolimus and mycophenolate mofetil, and prednisone.

RESULTS

At the intermediate-term follow-up, patients showed undetectable HIV viral load, CD4(+) T cell counts greater than 150 cells/μL, no HBV recurrence, and stable liver function. A liver allograft biopsy showed no evidence of acute cellular rejection. Both patients survived at 36-42 mo of follow-up.

CONCLUSION

This is the first report of ABOi-LT in HIV-HBV recipients with good intermediate-term outcomes, suggesting that ABOi-LT may be feasible and safe for HIV-HBV coinfected patients with ESLD.

Unveiling the degraded electron durability in reduced-dimensional perovskites

The operational stability of reduced-dimensional metal halide perovskites (RD-MHPs) lags far behind the practical requirements for future high-definition displays. Thereinto, the electron durability of RD-MHPs plays a critical role in stable LEDs during continuous operation, however, it still lacks adequate research and a deep understanding. Herein, the electron durability and deterioration mechanism of phenethylammonium (PEA⁺)-modified RD-MHPs are systematically conducted through an in situ photoelectron spectroscopy technique by implementing tunable electron-beam radiation to simulate device operation. The formation of detrimental metallic lead (Pb⁰) caused by the reduction of lead ions (Pb²⁺) is observed along with the decomposition of PEA⁺ under electron-beam radiation, thereby changing the photophysical properties of PEA⁺-doped RD-MHPs. These results provide deep insight into the process of how injected electrons affect the performance of PEA⁺-doped perovskite LEDs, which may also provide potential guidance for designing robust and effective organic spacers for RD-MHPs.

Regulating Charge Carrier Recombination in the Interconnecting Layer to Boost the Efficiency and Stability of Monolithic Perovskite/Organic Tandem Solar Cells

The charge carriers of single-junction solar cells can be fluently extracted and then collected by electrodes, leading to weak charge carrier accumulation and low energy loss (E_loss ). However, in tandem solar cells (TSCs), it is a considerable challenge to obtain a balance between the densities of the holes and electrons extracted from the two respective subcells to facilitate an efficient recombination in the interconnecting layer (ICL). Herein, a charge-carrier-dynamic management strategy for inorganic perovskite/organic TSCs is proposed, centered on the simultaneous regulation of the defect states of CsPbI_1.9 Br_1.1 perovskite in the front subcell and hole transport ability from the perovskite to ICL. The target hole density on the perovskite surface and the hole loss before reaching the ICL are significantly improved. As a result, the hole/electron density offset in the ICL can be effectively narrowed, leading to a balanced charge carrier recombination, which reduces the E_loss in TSCs. The resulting inorganic perovskite/organic 0.062-cm² TSC exhibits a remarkable power conversion efficiency (PCE) of 23.17% with an ultrahigh open-circuit voltage (V_oc ) of 2.15 V, and the PCE of the 1.004-cm² device (21.69%) exhibited a weak size-dependence. This charge-carrier-dynamic management strategy can also effectively enhance the operational and ultraviolet-light stabilities of the TSCs.

Bio-Inspired Pangolin Design for Self-Healable Flexible Perovskite Light-Emitting Diodes

Despite tremendous developments in the luminescene performance of perovskite light-emitting diodes (PeLEDs), the brittle nature of perovskite crystals and their poor crystallinity on flexible substrates inevitably lead to inferior performance. Inspired by pangolins' combination of rigid scales and soft flesh, we propose a bionic structure design for self-healing flexible PeLEDs by employing a polymer-assisted crystal regulation method with a soft elastomer of diphenylmethane diisocyanate polyurethane (MDI-PU). The crystallinity and flexural strain resistance of such perovskite films on plastics with silver-nanowire-based flexible transparent electrodes are highly enhanced. The detrimental cracks induced during repeated deformation can be effectively self-healed under heat treatment via intramolecular/intermolecular hydrogen bonds with MDI-PU. Upon collective optimization of the perovskite films and device architecture, the blue-emitting flexible PeLEDs can achieve a record external quantum efficiency of 13.5% and high resistance to flexural strain, which retain 87.8 and 80.7% of their initial efficiency after repeated bending and twisting operations of 2000 cycles, respectively.

Unraveling the Hole-Transport-Layer-Manipulated Carrier Transfer Dynamics in Perovskite Light-Emitting Diodes

Charge transfer dynamics is decisive for the performance of perovskite light emitting diodes (PeLEDs), and deep insight into the charge transfer process inside the working device is indispensable. Here, the influence of the hole transport layer on charge transport and recombination processes in PeLEDs is investigated via impedance spectroscopy. The results demonstrate that the rational interfacial energy level alignment can improve the radiative recombination by reducing the leakage current and carrier transport resistance. Shockley-Read-Hall recombination and Auger recombination enlarge the lifetime of carrier transfer in the working devices as determined from the electroluminescence spectrum. Our work provides a distinctive and reliable method to explore the charge transfer property and highlights the importance of interfaces to boost the performance of PeLEDs.

[Microbiota structure and diversity in Aedes albopictus at different developmental stages]

OBJECTIVE

To investigate the diversity and composition of microflora in laboratory-reared Aedes albopictus at different developmental stages and larval habitat waters.

METHODS

The larval habitat waters and different developmental stages of laboratory-reared A. albopictus were collected, and the V3 and V4 regions of the bacterial 16S rRNA gene were sequenced using Illumina Miseq next-generation sequencing. The abundance and diversity of the microflora were examined using alpha diversity index in A. albopictus at different developmental stages, and the difference in the microflora compositions was compared in A. albopictus at different developmental stages using principal component analysis (PCA). In addition, the species composition and relative abundance of microflora in A. albopictus at different developmental stages were described using histograms and Venn diagrams.

RESULTS

A total of 16 phyla, 30 classes, 72 orders, 129 families and 224 genera of bacteria were detected in larval habitat waters and different developmental stages of A. albopictus. The highest bacterial diversity was seen in larval A. albopictus, with Chao index of 125.20 ± 30.48 and Shannon diversity index of 2.04 ± 0.39, which were comparable to those (Chao index of 118.52 ± 15.07 and Shannon diversity index of 2.15 ± 0.30) in larval habitat waters (t = 0.35 and -0.41, both P values > 0.05). The bacterial abundance and evenness were significantly greater in female adults than in male adults (Chao index: 42.50 ± 3.54 vs. 18.50 ± 2.13, t = 8.23, P < 0.05; Shannon diversity index: 1.25 ± 1.67 vs. 0.50 ± 0.05, t = 6.00, P < 0.05). Proteobacteria, Bacteroidota, Actinobacteriota and Finnicutes were four common phyla of bacteria at each developmental stage of A. albopictus, with Proteobacteria dominated at the pupal stage (90.36%), Bacteroidota dominated at the adult stage (46.01% in female adults and 86.11% in male adults), and Actinobacteriota dominated at the larval stage (32.10%). Elizabethkingia and Rahnella 1 were common dominant genera of bacteria at each developmental stage of A. albopictus, with Rahnellal as the major component at the pupal stage (87.56%), Elizabethkingia as the main component at the adult stage (46.01% in female adults and 86.11% in male adults, respectively), and Microbacteria as the dominant bacterial genus at the larval stage (12.11%). In addition, Delftia, Elizabethkingia, Romboutsia, Serratia, Rahnella 1, Enterococcus and Microbacterium were common genera of bacteria at each developmental stage of A. albopictus, with Edaphobaculum dominated at the larval stage (17.54%) and Sphingobacterium dominated in larval habitat waters (13.93%).

CONCLUSIONS

There are differences in the composition of symbiotic bacteria at different developmental stages of A. albopictus; however, similar microflora diversity is maintained at the phylum level. The microflora diversity is comparable in larvae and larval habitat waters of A. albopictus.

Topological approach of liver segmentation based on 3D visualization technology in surgical planning for split liver transplantation

BACKGROUND

Split liver transplantation (SLT) is a complex procedure. The left-lateral and right tri-segment splits are the most common surgical approaches and are based on the Couinaud liver segmentation theory. Notably, the liver surface following right tri-segment splits may exhibit different degrees of ischemic changes related to the destruction of the local portal vein blood flow topology. There is currently no consensus on preoperative evaluation and predictive strategy for hepatic segmental necrosis after SLT.

AIM

To investigate the application of the topological approach in liver segmentation based on 3D visualization technology in the surgical planning of SLT.

METHODS

Clinical data of 10 recipients and 5 donors who underwent SLT at Shenzhen Third People’s Hospital from January 2020 to January 2021 were retrospectively analyzed. Before surgery, all the donors were subjected to 3D modeling and evaluation. Based on the 3D-reconstructed models, the liver splitting procedure was simulated using the liver segmentation system described by Couinaud and a blood flow topology liver segmentation (BFTLS) method. In addition, the volume of the liver was also quantified. Statistical indexes mainly included the hepatic vasculature and expected volume of split grafts evaluated by 3D models, the actual liver volume, and the ischemia state of the hepatic segments during the actual surgery.

RESULTS

Among the 5 cases of split liver surgery, the liver was split into a left-lateral segment and right tri-segment in 4 cases, while 1 case was split using the left and right half liver splitting. All operations were successfully implemented according to the preoperative plan. According to Couinaud liver segmentation system and BFTLS methods, the volume of the left lateral segment was 359.00 ± 101.57 mL and 367.75 ± 99.73 mL, respectively, while that measured during the actual surgery was 397.50 ± 37.97 mL. The volume of segment IV (the portion of ischemic liver lobes) allocated to the right tri-segment was 136.31 ± 86.10 mL, as determined using the topological approach to liver segmentation. However, during the actual surgical intervention, ischemia of the right tri-segment section was observed in 4 cases, including 1 case of necrosis and bile leakage, with an ischemic liver volume of 238.7 mL.

CONCLUSION

3D visualization technology can guide the preoperative planning of SLT and improve accuracy during the intervention. The simulated operation based on 3D visualization of blood flow topology may be useful to predict the degree of ischemia in the liver segment and provide a reference for determining whether the ischemic liver tissue should be removed during the surgery.

Reconstructing the portal vein through a posterior pancreatic tunnel: New choice for portal vein thrombosis during liver transplantation

BACKGROUND

Thrombectomy and anatomical anastomosis (TAA) has long been considered the optimal approach to portal vein thrombosis (PVT) in liver transplantation (LT). However, TAA and the current approach for non-physiological portal reconstructions are associated with a higher rate of complications and mortality in some cases.

AIM

To describe a new choice for reconstructing the portal vein through a posterior pancreatic tunnel (RPVPPT) to address cases of unresectable PVT.

METHODS

Between August 2019 and August 2021, 245 adult LTs were performed. Forty-five (18.4%) patients were confirmed to have PVT before surgery, among which seven underwent PV reconstruction via the RPVPPT approach. We retrospectively analyzed the surgical procedure and postoperative complications of these seven recipients that underwent PV reconstruction due to PVT.

RESULTS

During the procedure, PVT was found in all the seven cases with significant adhesion to the vascular wall and could not be dissected. The portal vein proximal to the superior mesenteric vein was damaged in one case when attempting thrombolectomy, resulting in massive bleeding. LT was successfully performed in all patients with a mean duration of 585 min (range 491-756 min) and mean intraoperative blood loss of 800 mL (range 500-3000 mL). Postoperative complications consisted of chylous leakage (n = 3), insufficient portal venous flow to the graft (n = 1), intra-abdominal hemorrhage (n = 1), pulmonary infection (n = 1), and perioperative death (n = 1). The remaining six patients survived at 12-17 mo follow-up.

CONCLUSION

The RPVPPT technique might be a safe and effective surgical procedure during LT for complex PVT. However, follow-up studies with large samples are still warranted due to the relatively small number of cases.

Strategies to Improve the Stability of Perovskite Light-Emitting Diodes: Progress and Perspective

Perovskite light-emitting diodes (PeLEDs) featuring excellent electroluminescent (EL) characteristics and facile production have been emerging as promising candidates for next-generation high-definition displays. In recent years, tremendous advances have been achieved in the EL efficiency of PeLEDs. However, their poor operational stability impedes practical applications. Particularly, the severe spectral instability of pure-blue and pure-red PeLEDs lags far behind the requirements of commercial displays. In this Perspective, the critical factors related to device degradation are first summarized, including perovskite crystal defects, unbalanced charge injection, Auger recombination, and Joule heating. Then, the recent progress in improving the operational and spectral stabilities is reviewed in categories. Considering the present achievements, we provide potential research directions for further development of stable PeLEDs.

CsPbBr3 microarrays with tunable periodicity, optoelectronic and field emission properties using self-assembled polystyrene template and co-evaporation method

The booming growth of all inorganic cesium lead halide perovskites in optoelectronic applications has prompted extensive research interest in the fabrication of ordered nanostructures or microarrays for enhanced device performances. However, the high cost and complexity of commercial lithographic approaches impede the facile fabrication of perovskite microarrays. Herein, CsPbBr₃ microarrays with tunable periodicities have been fabricated using a self-assembled polystyrene nanosphere template and a co-evaporation method. The periodicity of CsPbBr₃ microarrays is precisely manipulated by simply modifying the size of polystyrene nanospheres. These microarrays are beneficial for light harvesting, leading to better light absorption ability and prolonged photoinduced carrier lifetime. The longest average carrier lifetime of 58.3 ns is obtained for CsPbBr₃ microarrays with a periodicity of 1.0 μm. More importantly, the periodic structures of CsPbBr₃ microarrays result in a tunable density of emitter tips in field emission devices. Compared to compact CsPbBr₃ films, a 68.2% decrease of the turn-on field is observed for CsPbBr₃ microarrays when the periodicity is 150 nm. The higher density of emitter tips leads to larger local field enhancement, and hence the largest field enhancement factor of 3346.6. Finally, a good emission current stability for CsPbBr₃ microarray-based field emission devices has been demonstrated.

[Surveillance of Culex mosquitoes in Jiangsu Province from 2018 to 2019]

OBJECTIVE

To investigate the distribution and density of Culex mosquito populations and the resistance of Culex pipiens pallens to insecticides in Jiangsu Province in 2018 and 2019.

METHODS

During the period from June to October in 2018 and 2019, six counties (districts, cities) were sampled in southern, northern and central Jiangsu Province as surveillance sites. The density of Culex mosquitoes was measured overnight using the light trapping technique. In addition, Culex pipiens pallens mosquitoes were collected from Hai'an of Nantong City and Yandu District of Yancheng City, central Jiangsu Province, and the sensitivity of female first filial generations to dichlorodiphenyltrichloroethane (DDT), malation, proposur, beta cypermethrin and deltamethrin was tested using the standard WHO insecticide susceptibility test assay.

RESULTS

A total of 104 423 Culex mosquitoes were captured in six surveillance sites of Jiangsu Province in 2018 and 2019, and Culex quinquefasciatus (49.11%), Culex pipiens pallens (28.38%), and Culex tritaeniorhynchus (21.04%) were predominant species. The density of Culex mosquitoes started to increase since early June, peaked in July and tended to be low in late October. Culex pipiens pallens mosquitoes captured from Hai'an was susceptible to malation, while those from Yandu District were moderately resistant to malation. Culex pipiens pallens mosquitoes from both Yandu and Hai'an were moderately resistant to proposur, and were resistant to DDT, beta cypermethrin and deltamethrin.

CONCLUSIONS

Culex quinquefasciatus, Culex pipiens pallens and Culex tritaeniorhynchus are predominant Culex species in Jiangsu Province. Culex pipiens pallens is resistant to DT, beta cypermethrin and deltamethrin in central Jiangsu Province.

[Study on emergency metabolic changes of Anopheles sinensis larvae following exposure to deltamethrin]

OBJECTIVE

To analyze the changes of small molecular metabolites in the larvae of a deltamethrin-sensitive strain of Anopheles sinensis following exposure to deltamethrin, so as to provide the scientific basis for investigating the metabolic pathway and screening metabolic markers of deltamethrin in An. sinensis.

METHODS

The 50% and 75% lethal concentrations (LC₅₀ and LC₇₅) of deltamethrin against the larvae of a deltamethrin-sensitive strain of An. sinensis were calculated in laboratory. The type and content of An. sinensis larvae metabolites were detected using high performance liquid chromatography and mass spectrometry (LC-MS/MS) following exposure to deltamethrin at LC₅₀ and LC₇₅ for 30 min and 24 h, and the changes of metabolites were analyzed.

RESULTS

The LC₅₀ and LC₇₅ values of deltamethrin were 4.36 × 10^-3 µg/mL and 1.12 × 10^-2 µg/mL against thelarvae of a deltamethrin-sensitive strain of An. sinensis. Following exposure of the larvae of a deltamethrin-sensitive strain of An. sinensis to deltamethrin at LC₅₀ and LC₇₅ for 30 min, the differential metabolites mainly included organic oxygen compounds, carboxylic acid and its derivatives, fatty acyl and pyrimidine nucleotides, with reduced glucose levels. Following exposure for 24 h, the differential metabolites mainly included organic oxygen compounds, carboxylic acid and its derivatives, aliphatic acyl and purine nucleotides, with increased glucose level detected.

CONCLUSIONS

Carbohydrate, carboxylic acid and its derivatives, fatty acyls, amino acids and their derivatives may play important roles in deltamethrin metabolism in the larvae of a deltamethrin-sensitive strain of An. sinensis.

High-Light-Tolerance PbI2 Boosting the Stability and Efficiency of Perovskite Solar Cells

Excess lead iodide (PbI₂) plays a crucial role in passivating the defects of perovskite films and boosting the power conversion efficiency (PCE) of perovskite solar cells (PSCs). However, the photolysis of PbI₂ is easily triggered by light illumination, which accelerates the decomposition of perovskite materials and weakens the long-term stability of PSCs. Herein, the high light tolerance of lead iodide (PbI₂) is reported by introducing an electron-donor molecule, namely, 2-thiophenecarboxamide (2-TCAm), to strengthen the [PbX₆]^4- frame. Characterization reveals that the retarded decomposition of PbI₂ is attributed to the interactions between Pb²⁺ and the organic functional groups in 2-TCAm as well as the optimized distribution of PbI₂. The crystallization and morphology of 2-TCAm-doped perovskite films are improved simultaneously. The 2-TCAm-based PSCs achieve a 16.8% increase in PCE and nearly 12 times increase in the lifetime as compared to the reference device. The demonstrated method provides insight into the stability of PbI₂ and its influence on PSCs.

Surface-induced phase engineering and defect passivation of perovskite nanograins for efficient red light-emitting diodes

Organic-inorganic hybrid lead halide perovskites are potential candidates for next-generation light-emitting diodes (LEDs) in terms of tunable emission wavelengths, high electroluminescence efficiency, and excellent color purity. However, the device performance is still limited by severe non-radiative recombination losses and operational instability due to a high degree of defect states on the perovskite surface. Here, an effective surface engineering method is developed via the assistance of guanidinium iodide (GAI), which allows the formation of surface-2D heterophased perovskite nanograins and surface defect passivation due to the bonding with undercoordinated halide ions. Efficient and stable red-emission LEDs are realized with the improved optoelectronic properties of GAI-modified perovskite nanograins by suppressing the trap-mediated non-radiative recombination loss. The champion device with a high color purity at 692 nm achieves an external quantum efficiency of 17.1%, which is 2.3 times that of the control device. Furthermore, the operational stability is highly improved, showing a half-lifetime of 563 min at an initial luminance of 1000 cd m^-2. The proposed GAI-assisted surface engineering is a promising approach for defect passivation and phase engineering in perovskite films to achieve high-performance perovskite LEDs.

[Strategies and studies of malaria vector control in Jiangsu Province]

Malaria was one of the major infectious diseases in Jiangsu Province, where Anopheles sinensis and An. anthropophagus are main vectors for malaria transmission. Following the concerted efforts for decades, the goal of malaria elimination was achieved in Jiangsu Province in 2019, and the vector control strategy has played a vital role during the progress towards malaria elimination in Jiangsu Province. Hereby, we review the historical distribution and ecological features of An. sinensis and An. anthropophagus and describe vector control strategies at different stages of malaria control in Jiangsu Province. In addition, the advances in the research of vector biology and control in Jiangsu Province are discussed, including vector identification, strain colonization, susceptibility to malaria parasites and insecticide resistance.

Interaction of the Cation and Vacancy in Hybrid Perovskites Induced by Light Illumination

Mixed A-site engineering is an emerging strategy to overcome the difficulties in realizing high-quality perovskite films together with high ambient stability. Particularly, the α-FACsPbI₃-based hybrid perovskites have been considered as a promising candidate for solar cell applications. However, the degradation mechanism of α-FACsPbI₃ hybrid perovskites induced by light illumination remains unclear. Here, the illumination-caused instability of α-FACsPbI₃ hybrid perovskites is investigated using various surface detection technologies, including photoelectron spectroscopy, scanning electron microscopy, and grazing incidence X-ray diffraction. The experimental findings reveal that the A-site vacancies arise from the migration of Cs⁺ cations from the perovskite surface into the bulk under light illumination, while their content is dependent on the light energy. The visible light enlarges the crystal lattice on the perovskite surface, leading to the Cs⁺ cation migration along with the lattice distortion of the PbI₆^4- octahedron and phase separation. However, the ultraviolet light further causes a stronger interaction between FA⁺ and [PbI₆]^4-, leading to the partial decomposition of [PbI₆]^4- into Pb⁰ and I^-. These results enrich the photodegradation mechanism, guiding the design of efficient and stable perovskite solar cells through surface passivation to suppress the Cs⁺ cation migration and to increase the octahedron dissociation energy.

Hierarchically Manipulated Charge Recombination for Mitigating Energy Loss in CsPbI2Br Solar Cells

All-inorganic perovskite cesium lead iodide/bromide (CsPbI₂Br) is considered as a robust absorber for perovskite solar cells (PSCs) because of its excellent thermal stability that guarantees its long-term operation stability. Efficient CsPbI₂Br PSCs are available when obtaining low energy loss, which needs efficient charge generation, less charge recombination, and balanced charge extraction. However, numerous traps in perovskites hinder the photon-electron conversion process. Herein, hierarchical manipulation of charge recombination is proposed for CsPbI₂Br PSCs featuring low energy loss. Nonselective trap reduction and selective halogen vacancy passivation are performed using 2,2'-(ethylenedioxy)diethylamine and phenylbutylammonium iodide for the bottom and top contacts, respectively. Because of all-around suppressed charge recombination, balanced charge extraction and suppressed hysteresis are realized. The champion PSC achieves an open-circuit voltage of 1.30 eV, a fill factor of 80.2%, and a power conversion efficiency of 16.6% that is 28.6% higher than that of the reference device. Moreover, the thermostability of PSCs is simultaneously enhanced because of the limited defect-assisted degradation.

Recent advances in interface engineering of all-inorganic perovskite solar cells

All-inorganic perovskite solar cells (PSCs) have become one of the most attractive research fields in recent years due to their excellent thermal stability and light stability as compared with their organic-inorganic hybrid counterparts. However, there is still a long way to go for their commercial application due to their low efficiency and poor stability under humidity conditions. Herein, an overview of the recent progress of all-inorganic PSCs based on interface engineering is provided. The main roles of interface engineering, adjusting energy-level alignment, enhancing charge transport capacity, passivating interface defects, modulating morphology of perovskite films, stabilizing perovskite phase, broadening spectral absorption, eliminating electrical hysteresis and enhancing operational stability, are summarized with examples, which paves the way for highly efficient and stable all-inorganic PSCs. Some of the latest progress in incorporating dopants to charge transport materials and modifying interface properties in all-inorganic PSCs are also covered.

[Clinical features of coronavirus disease 2019 in children aged <18 years in Jiangxi, China: an analysis of 23 cases]

OBJECTIVE

To study the clinical features of coronavirus disease 2019 (COVID-19) in children aged <18 years.

METHODS

A retrospective analysis was performed from the medical data of 23 children, aged from 3 months to 17 years and 8 months, who were diagnosed with COVID-19 in Jiangxi, China from January 21 to February 29, 2020.

RESULTS

Of the 23 children with COVID-19, 17 had family aggregation. Three children (13%) had asymptomatic infection, 6 (26%) had mild type, and 14 (61%) had common type. Among these 23 children, 16 (70%) had fever, 11 (48%) had cough, 8 (35%) had fever and cough, and 8 (35%) had wet rales in the lungs. The period from disease onset or the first nucleic acid-positive detection of SARS-CoV-2 to the virus nucleic acid negative conversion was 6-24 days (median 12 days). Of the 23 children, 3 had a reduction in total leukocyte count, 2 had a reduction in lymphocytes, 2 had an increase in C-reactive protein, and 2 had an increase in D-dimer. Abnormal pulmonary CT findings were observed in 12 children, among whom 9 had patchy ground-glass opacities in both lungs. All 23 children received antiviral therapy and were recovered.

CONCLUSIONS

COVID-19 in children aged <18 years often occurs with family aggregation, with no specific clinical manifestation and laboratory examination results. Most of these children have mild symptoms and a good prognosis. Epidemiological history is of particular importance in the diagnosis of COVID-19 in children aged <18 years.

Narrow Bandpass and Efficient Semitransparent Organic Solar Cells Based on Bioinspired Spectrally Selective Electrodes

The visual aesthetic that involves color, brightness, and glossiness is of great importance for building integrated photovoltaics. Semitransparent organic solar cells (ST-OSCs) are thus considered as the most promising candidate due to their superiority in transparency and efficiency. However, the realization of high color purity with narrow bandpass transmitted light usually causes the severely suppressed transparency in ST-OSCs. Herein, we present a spectrally selective electrode (SSE) by imitating the integrating strategy of beetle cuticle for achieving narrow bandpass ST-OSCs with high efficiency and long-term stability. The proposed SSE allows for efficient light-selective passage, leading to tunable narrow bandpass transmitted light from violet to red. An optimized power conversion efficiency of 15.07% is achieved for colorful ST-OSCs, which exhibit color purity close to 100% and a peak transmittance approaching 30%. Long-term stability is also improved for ST-OSCs made with this SSE due to the light-rejecting and the moisture-blocking abilities. The realization of bright and colorful ST-OSCs also indicates the application potential of SSEs in light-emitting diodes, lasers, and photodetectors.

Rational Interface Engineering for Efficient Flexible Perovskite Light-Emitting Diodes

Although perovskite light-emitting diodes (PeLEDs) are promising for next-generation displays and lighting, their efficiency is still considerably below that of conventional inorganic and organic counterparts. Significant efforts in various aspects of the electroluminescence process are required to achieve high-performance PeLEDs. Here, we present an improved flexible PeLED structure based on the rational interface engineering for energy-efficient photon generation and enhanced light outcoupling. The interface-stimulated crystallization and defect passivation of the perovskite emitter are synergistically realized by tuning the underlying interlayer, leading to the suppression of trap-mediated nonradiative recombination losses. Besides approaching highly emissive perovskite layers, the outcoupling of trapped light is also enhanced by combining the silver nanowires-based electrode with quasi-random nanopatterns on flexible plastic substrate. Upon the collective optimization of the device structure, a record external quantum efficiency of 24.5% is achieved for flexible PeLEDs based on green-emitting CsPbBr₃ perovskite.

[Clinical features of coronavirus disease 2019 in children aged <18 years in Jiangxi, China: an analysis of 23 cases]

OBJECTIVE

To study the clinical features of coronavirus disease 2019 (COVID-19) in children aged <18 years.

METHODS

A retrospective analysis was performed from the medical data of 23 children, aged from 3 months to 17 years and 8 months, who were diagnosed with COVID-19 in Jiangxi, China from January 21 to February 29, 2020.

RESULTS

Of the 23 children with COVID-19, 17 had family aggregation. Three children (13%) had asymptomatic infection, 6 (26%) had mild type, and 14 (61%) had common type. Among these 23 children, 16 (70%) had fever, 11 (48%) had cough, 8 (35%) had fever and cough, and 8 (35%) had wet rales in the lungs. The period from disease onset or the first nucleic acid-positive detection of SARS-CoV-2 to the virus nucleic acid negative conversion was 6-24 days (median 12 days). Of the 23 children, 3 had a reduction in total leukocyte count, 2 had a reduction in lymphocytes, 2 had an increase in C-reactive protein, and 2 had an increase in D-dimer. Abnormal pulmonary CT findings were observed in 12 children, among whom 9 had patchy ground-glass opacities in both lungs. All 23 children received antiviral therapy and were recovered.

CONCLUSIONS

COVID-19 in children aged <18 years often occurs with family aggregation, with no specific clinical manifestation and laboratory examination results. Most of these children have mild symptoms and a good prognosis. Epidemiological history is of particular importance in the diagnosis of COVID-19 in children aged <18 years.

Management of Delayed Fluorophor-Sensitized Exciton Harvesting for Stable and Efficient All-Fluorescent White Organic Light-Emitting Diodes

White organic light-emitting diodes (WOLEDs) using thermally activated delayed fluorescence (TADF)-based single emissive layer (SEL) have attracted enormous attention because of their simple device structure and full exciton utilization potential for high efficiency. However, WOLEDs made of an all-TADF SEL usually exhibit serious efficiency roll-off and poor color stability due to serious exciton-annihilation and unbalanced radiative decays of different TADF emitters. Herein, a new strategy is proposed to manipulate the TADF-sensitized fluorescence process by combining dual-host systems of high triplet energy with a conventional fluorescent emitter of complementary color. The multiple energy-funneling paths are modulated and short-range Dexter energy transfer is largely suppressed due to the steric effect of peripheral tert-butyl group in the blue TADF sensitizer. The resulting all-fluorescent WOLEDs achieve an unprecedentedly high external quantum efficiency of 21.8% with balanced white emission of Commission Internationale de l'Eclairage coordinate of (0.292, 0.343), accompanied with good color stability, reduced efficiency roll-off, and prolonged operational lifetime. These findings demonstrate the validity of this strategy for precisely allocating the exciton harvesting in SEL WOLEDs.

Recent progress of light manipulation strategies in organic and perovskite solar cells

Organic and perovskite solar cells are suffering from the insufficient utilization of incident light and thus low light harvesting efficiency despite their rapid progress in the past decade. In this regard, light manipulation strategies have attracted numerous attention to solve this inherent limit. Herein, the recent advances in light manipulation techniques in this area are overviewed. The light manipulation mechanisms are illustrated to classify the structures. Various light manipulation structures, fabrication techniques, and corresponding results are given and discussed, addressing the suppression of surface reflection, nano/micro-structure-induced light scattering, and the plasmonic effects with periodic metallic patterns and metallic nanoparticles. A brief perspective on future research is also proposed for pursuing broadband light harvesting.

Rational Molecular Design of Dibenzo[a,c]phenazine-Based Thermally Activated Delayed Fluorescence Emitters for Orange-Red OLEDs with EQE up to 22.0

The design and synthesis of highly efficient thermally activated delayed fluorescence (TADF) emitters with an electroluminescence wavelength beyond 600 nm remains a great challenge for organic light-emitting diodes (OLEDs). To solve this issue, three TADF molecules, xDMAC-BP (x = 1, 2, 3), are developed in combination with the rigid planar dibenzo[a,c]phenazine (BP) acceptor core and different numbers of 9,9-dimethylacridan (DMAC) donors. All these emitters possess stable internal charge transfer and a large dihedral angle between the donors and planar BP core. The emission wavelength can be regulated from 541 to 605 nm by increasing the number of the donor DMAC units because of the controllable tuning of the intramolecular charge transfer effect and the molecular geometrical structure. The photoluminescence quantum yields of these emitters are improved from 42 to 89% with the increase in the number of DMAC units. The orange-red OLEDs employing the xDMAC-BP emitters exhibit maximum external quantum efficiency (EQE) of 22.0% at 606 nm, which is the highest EQE of the previously reported TADF OLEDs exceeding 600 nm.

High-Efficiency Perovskite Light-Emitting Diodes with Synergetic Outcoupling Enhancement

Perovskite light-emitting diodes (PeLEDs) show great application potential in high-quality flat-panel displays and solid-state lighting due to their steadily improved efficiency, tunable colors, narrow emission peak, and easy solution-processing capability. However, because of high optical confinement and nonradiative charge recombination during electron-photon conversion, the highest reported efficiency of PeLEDs remains far behind that of their conventional counterparts, such as inorganic LEDs, organic LEDs, and quantum-dot LEDs. Here a facile route is demonstrated by adopting bioinspired moth-eye nanostructures at the front electrode/perovskite interface to enhance the outcoupling efficiency of waveguided light in PeLEDs. As a result, the maximum external quantum efficiency and current efficiency of the modified cesium lead bromide (CsPbBr₃ ) green-emitting PeLEDs are improved to 20.3% and 61.9 cd A^-1 , while retaining spectral and angular independence. Further reducing light loss in the substrate mode using a half-ball lens, efficiencies of 28.2% and 88.7 cd A^-1 are achieved, which represent the highest values reported to date for PeLEDs. These results represent a substantial step toward achieving practical applications of PeLEDs.

High-Efficiency Perovskite Light-Emitting Diodes with Synergetic Outcoupling Enhancement

Perovskite light-emitting diodes (PeLEDs) show great application potential in high-quality flat-panel displays and solid-state lighting due to their steadily improved efficiency, tunable colors, narrow emission peak, and easy solution-processing capability. However, because of high optical confinement and nonradiative charge recombination during electron-photon conversion, the highest reported efficiency of PeLEDs remains far behind that of their conventional counterparts, such as inorganic LEDs, organic LEDs, and quantum-dot LEDs. Here a facile route is demonstrated by adopting bioinspired moth-eye nanostructures at the front electrode/perovskite interface to enhance the outcoupling efficiency of waveguided light in PeLEDs. As a result, the maximum external quantum efficiency and current efficiency of the modified cesium lead bromide (CsPbBr₃ ) green-emitting PeLEDs are improved to 20.3% and 61.9 cd A^-1 , while retaining spectral and angular independence. Further reducing light loss in the substrate mode using a half-ball lens, efficiencies of 28.2% and 88.7 cd A^-1 are achieved, which represent the highest values reported to date for PeLEDs. These results represent a substantial step toward achieving practical applications of PeLEDs.

Synergetic Transparent Electrode Architecture for Efficient Non-Fullerene Flexible Organic Solar Cells with >12% Efficiency

Flexible organic solar cells (OSCs) are considered one key component in wearable, intelligent electronics due to the unique capacity for highly flexible renewable energy sources. However, it is urgently required to enhance their efficiency, as it is far inferior to that of their conventional, glass-based counterparts. To boost the performance of flexible OSCs on plastic substrates, we here present a synergetic transparent electrode structure, which combines electrically conductive silver nanowires, a sol-gel-derived ZnO planarization layer, and imprinted light-trapping nanostructures. This synergetic composite electrode exhibits good properties in terms of optical transparency, electrical conductivity, mechanical flexibility, and low-temperature processability. As a result, the single-junction non-fullerene-based flexible OSCs achieve a power conversion efficiency exceeding 12% due to the synergetic interplay between broadband light trapping and suppressed charge recombination loss. Moreover, these flexible OSCs are repeatedly bendable in both inward and outward bending directions, retaining over 60% of the initial efficiency after 1000 cycles of the bending test at a 3.0 mm radius. These results convey a clear depiction of the practicality of flexible OSCs in a variety of high-performance flexible applications.

Multifunctional Silver Nanoparticle Interlayer-Modified ZnO as the Electron-Injection Layer for Efficient Inverted Organic Light-Emitting Diodes

The insufficient electron injection constitutes the major obstacle to achieving high-performance inverted organic light-emitting diodes (OLEDs). Here, a facile electron-injection architecture featuring a silver nanoparticle (AgNPs) interlayer-modified sol-gel-derived transparent zinc oxide (ZnO) ultrathin film is proposed and demonstrated. The optimized external quantum efficiencies of the developed inverted fluorescent and phosphorescent OLEDs capitalized on our proposed electron-injection structure reached 4.0 and 21.2% at a current density of 20 mA cm^-2 and increased by a factor of 1.90 and 2.86 relative to a reference device without the AgNP interlayer, while simultaneously reducing the operational voltage and substantially ameliorating the device efficiency. Detailed analyses reveal that the local surface plasmon resonance emanated from AgNPs plays three meaningful roles simultaneously: suppressing the surface plasmon polariton mode loss, aiding in energy-level alignments, and inducing and reinforcing the local exciton-plasmon coupling electric field. Among these interesting and multifunctional roles, the enhanced local exciton-plasmon coupling electric field dominates the electron injection enhancement and substantial increases the device efficiency. Additionally, the light-scattering effect also helps in recovering the trapped light energy flux and thus improves the device efficiency. The proposed approach and findings provide an alternative path to fabricate high-performance inverted OLEDs and other related organic electronic or optoelectronic devices.

Effects of propofol and surgery on neuropathology and cognition in the 3xTgAD Alzheimer transgenic mouse model

Background

Previous work suggests that anaesthesia and surgery amplify the pathology and cognitive impairment of animals made vulnerable via age or specific transgenes. We hypothesized that surgery under propofol anaesthesia, a widely used i.v. general anaesthetic, has minimal delayed cognitive and neuroinflammatory sequelae in a vulnerable mouse transgenic model.

Methods

We conducted caecal ligation and excision surgery in cognitively presymptomatic (11-month-old) 3xTgAD mice under i.p. propofol anaesthesia. Age-matched 3xTgAD control mice received vehicle or propofol without surgery. Morris water maze testing was conducted 3 and 15 weeks later. Brains were examined with quantitative immunohistochemistry for amyloid β plaques, tau pathology, and microglial activation. Acute changes in neuroinflammatory cytokines were assessed in separate cohorts at 6 h.

Results

We detected no significant differences between groups in escape latencies at either 3 or 15 weeks, but detected a significant effect of surgery in the probe test at both 3 and 15 weeks. Spatial working memory was unaffected at 16 weeks in any group. No effects of either propofol alone or propofol with surgery were detected on plaque formation, tau aggregates, or neuroinflammation. Acute biochemical assays detected no effects in brain interleukin-10 or interleukin-6 concentrations.

Conclusions

Surgery in a vulnerable transgenic mouse under propofol anaesthesia was associated with minimal to no changes in short- and long-term behaviour and no changes in neuropathology. This suggests that propofol anaesthesia is associated with better cognitive outcomes in the aged, vulnerable brain compared with inhalation anaesthesia.

Isolation, genetic identification and degradation characteristics of COD-degrading bacterial strain in slaughter wastewater

Contamination of water by meat production is an important and extensive environmental problem and even threat to human health. Biodegradation is a major mechanism which removes the pollutants from the environment. Therefore, the present study aimed to isolate and characterize a COD degrading bacteria which can effectively degrade slaughter wastewater. Six COD degrading bacteria were isolated from slaughtering waste water and sludge in Hunan a meat product Co., Ltd. And the COD degradation rate of each strain was determined by potassium permanganate method. Through observing morphologically and analyzing sequence to 16S rDNA, the highest COD degradation strain was Bacillus velezensis by preliminarily identified and classified, reaching 11.80%. The suitable conditions of the growth of Bacillus velezensis strain were 37 °C, pH 7.0, the peptone concentration 1.5%, and the yeast extract concentration 0.8%.

Preoperative Alfa-Fetoprotein and Fibrinogen Predict Hepatocellular Carcinoma Recurrence After Liver Transplantation Regardless of the Milan Criteria: Model Development with External Validation

BACKGROUND/AIMS

Patient selection is critically important in improving the outcomes of liver transplantation for hepatocellular carcinoma. The aim of the current study was to identify biochemical measures that could affect patient prognosis after liver transplantation.

METHODS

A total of 119 patients receiving liver transplantation for hepatocellular carcinoma were used to construct a model for predicting recurrence. The results were validated using an independent sample of 109 patients from independent hospitals. All subjects in both cohorts met the Hangzhou criteria.

RESULTS

Analysis of the discovery cohort revealed an association of recurrence with preoperative fibrinogen and AFP levels. A mathematical model was developed for predicting probability of recurrence within 5 years: Y = logit(P) = -4.595 + 0.824 ×fibrinogen concentration (g/L) + 0.641 × AFP score (1 for AFP<=20ng/ml, 2 for 20<AFP<=100ng/ml, 3 for 100<AFP<=200ng/ml, 4 for 200<AFP<=400ng/ml, 5 for AFP> 400ng/ml). At a cutoff score of -0.85, the area under the curve (AUC) was 0.819 in predicting recurrence (vs. 0.655 when using the Milan criteria). In the validation cohort, this model had reasonable performance in predicting 5-year overall survival (68.8% vs. 28.1% in using the -0.85 cutoff, p< 0.001) and disease-free survival (65.7% vs. 25.9%, p< 0.001). The sensitivity and specificity were 77.0% and 62.5%, respectively. The AUC of this newly developed model was similar to that with the Milan criteria (0.698 vs. 0.678). Surprisingly, the DFS in patients with score <= -0.85 under this model but not meeting the Milan criteria was similar to that in patients meeting the Milan criteria (53.8% vs. 60.0%, p=0.380).

CONCLUSIONS

Preoperative AFP and fibrinogen are useful in predicting recurrence of hepatocellular carcinoma after liver transplantation.

Balanced Partnership between Donor and Acceptor Components in Nonfullerene Organic Solar Cells with >12% Efficiency

Relative to electron donors for bulk heterojunction organic solar cells (OSCs), electron acceptors that absorb strongly in the visible and even near-infrared region are less well developed, which hinders the further development of OSCs. Fullerenes as traditional electron acceptors have relatively weak visible absorption and limited electronic tunability, which constrains the optical and electronic properties required of the donor. Here, high-performance fullerene-free OSCs based on a combination of a medium-bandgap polymer donor (FTAZ) and a narrow-bandgap nonfullerene acceptor (IDIC), which exhibit complementary absorption, matched energy levels, and blend with pure phases on the exciton diffusion length scale, are reported. The single-junction OSCs based on the FTAZ:IDIC blend exhibit power conversion efficiencies up to 12.5% with a certified value of 12.14%. Transient absorption spectroscopy reveals that exciting either the donor or the acceptor component efficiently generates mobile charges, which do not suffer from recombination to triplet states. Balancing photocurrent generation between the donor and nonfullerene acceptor removes undesirable constraints on the donor imposed by fullerene derivatives, opening a new avenue toward even higher efficiency for OSCs.