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The spatial distribution of precipitation anomalies during flood season and characteristics of drought and flood disasters in China are directly affected by the speed and stagnation of the East Asian summer monsoon (EASM). EASM is significantly affected by external forcing such as sea surface temperature, land surface processes, ice and snow cover, and internal dynamic anomalies of atmospheric circulation. The sea surface temperature (SST) anomaly and its evolution have always been important factors for predicting precipitation during the flood season, considering lead time and the strength of precipitation prediction in flood season.Based on the scientific understanding and application of the mechanism of El Niño-southern oscillation (ENSO) cycle and other Ocean SST on the key factors of EASM, the prediction skill of flood season precipitation is reviewed. According to a prediction evaluation spanning over 40 years of historical records, the prediction accuracy for different types of rainfall pattern, the prediction accuracy of rain types in 1981-1990, 1991-2000, 2001-2010, and 2011-2020 is 50%/30%, 60%/30%, 50%/40%, and 70%/50%, respectively. In other words, the prediction of the primary rainfall patterns during the flood season in China is closer to the observation, and the accuracy of predicting spatial distribution patterns of drought and flood has significantly improved. This improvement can be attributed to the in-depth understanding of the impact of SST on EASM activities and enhancements made to dynamic climate models. In the history of flood season prediction, there have been both successful and unsuccessful cases. The years with low prediction accuracy and significant flooding events are as follows: 1983, 1991, 1999, 2003, and 2014. The primary basis for prediction is analyzed, revealing that the limited understanding of the mechanism of SST affecting the EASM had a great impact on the skill of precipitation predictions during the flood season. Among these factors, the influence of different phases of the ENSO cycle, the asymmetry of ENSO's influence, the change in ENSO spatial patterns, and the influence of other local seas, such as the Indian Ocean SST anomaly, all play important roles.The importance of multi-factor and multi-scale synergy theory and application, as well as the technical support of the objectification method for prediction, are emphasized in summarizing causes for low prediction skill cases. Finally, some suggestions for improving future flood season precipitation predictions are put forward, and it is emphasized that the development of a multi-factor and multi-time scale synergistic theory, an objective climate prediction method, and an integrated system for monitoring, predictions and impact assessment will significantly enhance predictions and provide services for flood season precipitation.

Human eyes possess exceptional image-sensing characteristics such as an extremely wide field of view, high resolution and sensitivity with low aberration1. Biomimetic eyes with such characteristics are highly desirable, especially in robotics and visual prostheses. However, the spherical shape and the retina of the biological eye pose an enormous fabrication challenge for biomimetic devices2,3. Here we present an electrochemical eye with a hemispherical retina made of a high-density array of nanowires mimicking the photoreceptors on a human retina. The device design has a high degree of structural similarity to a human eye with the potential to achieve high imaging resolution when individual nanowires are electrically addressed. Additionally, we demonstrate the image-sensing function of our biomimetic device by reconstructing the optical patterns projected onto the device. This work may lead to biomimetic photosensing devices that could find use in a wide spectrum of technological applications.

This study investigated the effect of combined thymosin α1 and vitamin C (Tα1 + VitC) on the immunological responses of septic rats. Five groups were designed. The septic model was established by the cecal ligation puncture (CLP) method. The sham group did not undergo CLP, the model group was given normal saline solution, the Tα1 group was given Tα1 (200 µg/kg), the VitC group was given VitC (200 mg/kg), and the Tα1 + VitC group was given Tα1 + VitC. Specimens for immunological analyses were collected at 6, 12, 24, and 48 h posttreatment in each group except for the sham group (only at 48 h). CD4 + CD25 + T cells in the peripheral blood and dendritic cell (DC) proportions in the spleen were analyzed by flow cytometry. Tumor necrosis factor α (TNF-α), interleukin 6 (IL-6), transforming growth factor-β (TGF-ß1), and nuclear factor kappa-B (NF-κB) were measured by ELISA. CD4 + CD25 + T cells and OX62 + DCs levels significantly increased in the model group and decreased in the Tα1 and/or VitC treatment groups. Similarly, the levels of TNF-α, IL-6, TGF-ß1, and NF-κB significantly increased in the model group and decreased in the Tα1, VitC, and Tα1 + VitC groups, indicating that combined Tα1 and VitC therapy may help regulate the immunological state of patients with sepsis, thereby improving prognosis.

High-photoluminescence quantum yield (PLQY) is required to reach optimal performance in solar cells, lasers, and light-emitting diodes (LEDs). Typically, PLQY can be increased by improving the material quality to reduce the nonradiative recombination rate. It is in principle equally effective to improve the optical design by nanostructuring a material to increase light out-coupling efficiency (OCE) and introduce quantum confinement, both of which can increase the radiative recombination rate. However, increased surface recombination typically minimizes nanostructure gains in PLQY. Here a template-guided vapor phase growth of CH3NH3PbI3 (MAPbI3) nanowire (NW) arrays with unprecedented control of NW diameter from the bulk (250 nm) to the quantum confined regime (5.7 nm) is demonstrated, while simultaneously providing a low surface recombination velocity of 18 cm s-1. This enables a 56-fold increase in the internal PLQY, from 0.81% to 45.1%, and a 2.3-fold increase in OCEy to increase the external PLQY by a factor of 130, from 0.33% up to 42.6%, exclusively using nanophotonic design.

Extraordinary photovoltaic performance and intriguing optoelectronic properties of perovskite solar cells (PSCs) have aroused enormous interest from both academic research and photovoltaic (PV) industry. In order to bring PSC technology from laboratory to market, material stability, device flexibility, and scalability are important issues to address for vast production. Nevertheless, PSCs are still primarily prepared by solution methods which limit film scalability, while high-temperature processing of metal oxide electron transport layer (ETL) makes PSCs costly and incompatible with flexible substrates. Here, we demonstrate rarely-reported room-temperature radio frequency (RF) sputtered SnO2 as a promising ETL with suitable band structure, high transmittance, and excellent stability to replace its solution-processed counterpart. Power conversion efficiencies (PCEs) of 12.82% and 5.88% have been achieved on rigid glass substrate and flexible PEN substrate respectively. The former device retained 93% of its initial PCE after 192-hour exposure in dry air while the latter device maintained over 90% of its initial PCE after 100 consecutive bending cycles. The result is a solid stepping stone toward future PSC all-vapor-deposition fabrication which is being widely used in the PV industry now.

Metal halide perovskite has emerged as a promising material for light-emitting diodes. In the past, the performance of devices has been improved mainly by optimizing the active and charge injection layers. However, the large refractive index difference among different materials limits the overall light extraction. Herein, we fabricate efficient methylammonium lead bromide light-emitting diodes on nanophotonic substrates with an optimal device external quantum efficiency of 17.5% which is around twice of the record for the planar device based on this material system. Furthermore, optical modelling shows that a high light extraction efficiency of 73.6% can be achieved as a result of a two-step light extraction process involving nanodome light couplers and nanowire optical antennas on the nanophotonic substrate. These results suggest that utilization of nanophotonic structures can be an effective approach to achieve high performance perovskite light-emitting diodes.

PurposeThe incidence of seroma and postoperative pain after Gilbert type III inguinal hernia repair is high. To reduce postoperative complications, this study investigated the clinical efficacy of laparoscopic closed hernia ring combined with a patch repair for Gilbert type III indirect inguinal hernia.MethodsThrough a prospective randomized controlled study, a total of 193 patients with Gilbert type III indirect inguinal hernia admitted to Nanchong Central Hospital affiliated with Chuanbei Medical College from May 2020 to December 2021 were selected and randomly divided into the inner ring closed group (85 patients) and the inner ring non-closed group (95 patients). The patients in both groups underwent laparoscopic tension-free repair of their inguinal hernias. General information such as operative time, postoperative hospital stay, and hospital cost were compared between the two groups, and the patients were followed up at 1, 7, 14, 21, and 28 days and then 3, 6, and 12 months after surgery to compare complications such as incidence of seroma, volume of the seroma fluid, incidence of pain, and visual analogue scale (VAS) pain score.ResultsThere was no conversion to open procedures in any of the patients. The operation time of the closed group was significantly longer than that of the non-closed group (64.2 ± 12.2 vs. 55.3 ± 9.5 min, P 0.05). The postoperative follow-up period was 3–20 months, and no chronic pain or recurrence occurred during the postoperative follow-up period in either group.ConclusionsClosure of the hernia ring is safe and effective for laparoscopic hernia repair for Gilbert type III inguinal hernia, and it significantly reduces the incidence of postoperative seroma and further reduces the postoperative pain without increasing the risk of postoperative infection and recurrence.