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The effect of different linkages on thermal, electrochemical, photophysical, and optoelectronic properties was discussed in detail to illuminate the structure–property relationship of four δ-carboline derivatives, 5-(3′-(9H-carbazol-9-yl)-[1,1′-biphenyl]-3-yl)-5H-pyrido[3,2-b]indole (CzBPDCb), 3,3′-bis(5H-pyrido[3,2-b]indol-5-yl)-1,1′-biphenyl (BDCbBP), 5-(5-(3-(9H-carbazol-9-yl)phenyl)pyridin-3-yl)-5H-pyrido[3,2-b]indole (Cz35PyDCb), and 5-(6-(3-(9H-carbazol-9-yl)phenyl)pyridin-2-yl)-5H-pyrido[3,2-b]indole (Cz26PyDCb). Their triplet energies (ET = 2.78–2.96 eV) and the lowest unoccupied molecular orbital (LUMO) energy could be manipulated by the linkage and the number of δ-carboline units. These materials exhibited bipolar features with good hole- and electron-transporting properties. These host materials when doped with bis(3,5-difluoro-2-(2-pyridyl)phenyl-(2-carboxypyridyl)iridium(iii)) (FIrpic) demonstrated efficient blue phosphorescent organic light emitting diode (OLED) with reduced driving voltage, high efficiency, and negligible roll-off. Among these four materials, Cz35PyDCb performed as a host material for blue OLED with ideal current and power efficiencies (CEmax at 44.7 cd A−1, and PEmax at 40.2 lm W−1), as well as good external quantum efficiency (EQEmax at 22.3%). Most importantly, at the normal 1000 cd m−2 operation brightness, the efficiencies remained at 42.6 cd A−1 for CE (95% of CEmax), 31.7 lm W−1 for PE (79% of PEmax), and 20.1% for EQE (90% of EQEmax), which indicated well-balanced carriers transporting and good confinement of the triplet excitons in the emitting layer, even at high current density. Moreover, introduction of the δ-carboline moiety could improve the thermal and morphological stabilities. [ABSTRACT FROM AUTHOR]

High efficiency performance and color rendering index (CRI) are two main requirements for the applications of white organic light-emitting diodes (WOLEDs). We report successful fabrication of efficient and high-color-rendering phosphorescent WOLED by employing ultra-thin red emitter - spacer layer - ultra-thin green emitter architecture. By fine-tuning the thicknesses of emitting layers and spacer layer, we have obtained WOLED with a high CRI of 80 and high luminance efficiency (LE) of 29.2 cd A−1 which only rolls off to 22.8 cd A−1 at 1000 cd m−2. A typical WOLED for comparison exhibits a CRI below 40 and maximum LE of 15.8 cd A−1 which decreases to 11.4 cd A−1 at 1000 cd m−2. The superiority of ultra-thin device compared with typical device demonstrates utilizing ultra-thin emitting layer is a promising technique to achieve high performance organic light-emitting diode (OLED). [ABSTRACT FROM AUTHOR]

Abstract: As a typical industrial wastewater, coal gasification wastewater has poor biodegradability and high toxicity. In this paper, a laboratory-scale anaerobic–anoxic–oxic membrane reactor (A2O-MBR) system was developed to investigate the treatment ability of coal gasification wastewater. The removal capacity of each pollutants used in this system were determined at different hydraulic residence times (HRT) and mixed liquor recycle ratios (R). The experimental results showed that this system could effectively deal with COD and phenol removal and remain in a stable level when the operational parameters altered, while the nitrification was sensitive to operational conditions. The best performance was obtained at HRT of 48h and R of 3. The maximum removal efficiencies of COD, NH4 +-N and phenols were 97.4%, 92.8% and 99.7%, with final concentrations in the effluent of 71mg/L, 9.6mg/L and 3mg/L, respectively. Organics degradation and transformation were analyzed by GC/MS and it was found that anaerobic process played an important role in degradation of refractory compounds. [Copyright &y& Elsevier]

Purpose: The incomplete resection of non-muscle invasive bladder cancer (NMIBC) augments the risk of disease recurrence. Imaging-guided surgery by molecular probes represents a pivotal strategy for mitigating postoperative recurrence. Traditional optical molecular probes, primarily composed of antibodies/peptides targeting tumour cells and fluorescent groups, are challenged by the high heterogeneity of NMIBC cells, leading to inadequate probe sensitivity. We have developed a collagen-adhesive probe (CA-P) to target the collagen within the tumour microenvironment, aiming to address the issue of insufficient imaging sensitivity. Methods: The distribution characteristics of collagen in animal bladder cancer models and human bladder cancer tissues were explored. The synthesis and properties of CA-P were validated. In animal models, the imaging performance of CA-P was tested and compared with our previously reported near-infrared probe PLSWT7-DMI. The clinical translational potential of CA-P was assessed using human ex vivo bladder tissues. Results: The distribution of collagen on the surface of tumour cells is distinct from its expression in normal urothelium. In vitro studies have demonstrated the ability of the CA-P to undergo a "sol-gel" transition upon interaction with collagen. In animal models and human ex vivo bladder specimens, CA-P exhibits superior imaging performance compared to PLSWT7-DMI. The sensitivity of this probe is 94.1%, with a specificity of 81%. Conclusion: CA-P demonstrates the capability to overcome tumour cell heterogeneity and enhance imaging sensitivity, exhibiting favorable imaging outcomes in preclinical models. These findings provide a theoretical basis for the application of CA-P in intraoperative navigation for NMIBC. [ABSTRACT FROM AUTHOR]

Thermoelectric (TE) fibers are more suitable than films for portable or wearable devices. Herein, 2–3 nm thick poly (3,4‐ethylenedioxythiophene): poly (styrenesulfonate) (PEDOT:PSS) layer‐coated tellurium nanowires (PC‐Te NWs) are in situ prepared by a hydrothermal method. Then a series of PEDOT: PSS/PC‐Te NWs composite fibers are prepared by wet spinning and post‐treatment. The nanolayer prevents the agglomeration of the Te NWs and makes the NWs and PEDOT:PSS matrix have good compatibility, which results in the PC‐Te NWs content to a high value of 70 wt% and the fibers still with flexibility. The high aspect ratio of the PC‐Te NWs and the stress from the inner wall of the needle during spinning make the NWs ordered align along the composite fiber. Due to the large content and orientational arrangement of the PC‐Te NWs, as well as effective post‐treatment, an optimized composite fiber shows a power factor of 385.4 µW m−1 K−2 at 300 K, which is ≈4.9 times as high as the highest value of previously reported PEDOT:PSS/Te NWs‐based composite fibers. In addition, the composite fiber has good flexibility. The flexible TE generators assembled have excellent output performance. This work provides an effective strategy for the preparation of high‐performance flexible TE composite fibers. [ABSTRACT FROM AUTHOR]

On-chip micro-supercapacitors (MSCs) are one of the most promising devices to be integrated into micro-/nano-scale electronic devices for offering sufficient peak power and energy support. However, low operate voltage and limited energy density greatly inhibit their wider practical application. Herein, high-voltage on-chip MSCs based on Ti 3 C 2 T x MXene as a negative electrode and activated carbon as a positive electrode are designed and are simply manufactured via a novel cutting-spraying method. Through solving the excessive polarization of MXene, a single asymmetric on-chip MSCs can deliver a potential window up to 1.6 V in neutral electrolyte (PVA/Na 2 SO 4), and share a high areal capacitance of 7.8 mF cm−2 (a stack specific capacitance of 36.5 F cm−3) and a greatly improved energy density of 3.5 mWh cm−3 at a power density of 100 mW cm−3, which are much higher than other on-chip energy storage counterparts. Besides, MSCs show an excellent capacity retention (remaining 91.4% after 10 000 cycles). More importantly, MSCs can be easily enlarged as highly integrated array in series and/or in parallel on the silicon wafers. Evidently, this study opens up new avenues for developing high-voltage MXene-based MSCs used in on-chip electronics and portable devices. Image 1 • Asymmetric Ti 3 C 2 T x MXene-based on-chip micro-supercapacitors (MSCs) are designed for the first time. • The asymmetric high-voltage MXene-based on-chip MSCs possess excellent comprehensive electrochemical properties. • High-voltage MXene-based on-chip MSCs can be easily enlarged as highly integrated arrays on the silicon wafers. [ABSTRACT FROM AUTHOR]

The rapid development of silicon-based microelectronic devices urgently demand for compatibly silicon-based micro-supercapacitors (MSCs) with smaller size, higher power density, and higher integration density. However, there are still some challenges in fabricating silicon-based MSCs, such as weakly-connected interface and expensively-manufactured process. Here we demonstrate a scalable and low-cost treating-cutting-coating (TCC) manufacture platform for Ti 3 C 2 T x MXene-based on-chip MSCs. The hydrophilical treating of silicon/silicon dioxide (Si/SiO 2) surface can effectively enforce MXene-silicon interface adhesion, resulting in the improved integrity and uniformity of MXene films. Subsequently, cold laser-cutting followed by spin-coating can rapidly prepare the MXene-based electrodes on the kapton-masked Si/SiO 2 substrates. This as-obtained MSC displays a high areal and volumetric capacitance of 472 μF cm−2 and 21.4 F cm−3, incorporating with outstanding cycling stability of over 87.6% capacitance retention after 10 000 cycles. Evidently, this treating-cutting-coating manufacture process will support a general platform toward scalable on-chip energy storage devices based on 2D materials. Image 1 • We developed a scalable and low-cost TCC manufacture platform for silicon-based MSCs that can be extended to other MXenes. • The hydrophilical treating of silicon surface can effectively enforce MXene-silicon interface adhesion. • The as-prepared on-chip MSCs exhibit high capacity performance, high power density and outstanding cyclic capability. [ABSTRACT FROM AUTHOR]

Harvesting biomechanical energy from low-frequency human body motions is a challenging but promising approach to powering the future wearables. Herein, we report a linear-to-rotary hybrid nanogenerator (LRH-NG) to effectively harvest low-frequency body biomechanical energy via a frequency enhancement strategy. Remarkably, the generated current and voltage by the LRH-NG from human body movement are respectively enhanced up to 3.1 times and 3.6 times of that at the basic frequency (2 Hz). Furthermore, the LRH-NG was demonstrated as an on-body electricity generator that can sustainably power a body area network with a temperature sensor and a humidity sensor for personalized health care. The designed LRH-NG may open up a new approach for high-performance low-frequency wearable biomechanical energy harvesting as a sustainable and pervasive energy solution in the era of the Internet of things. Image 1 • Harvesting low-frequency biomechanical energy is challenging but promising approach to powering the future wearables. The linear-to-rotary hybrid nanogenerator (LRH-NG) can effectively convert the low-frequency biomechanical linear motions into high-frequency rotary motions. • The generated current and voltage by the LRH-NG from human body movement were enhanced up to 3.1 and 3.6 times of that at the basic frequency (2 Hz), respectively. • The energy generated from human walking by the LRH-NG with an enhancement factor of G f1 could power a body area network for personalized health care. • The designed LRH-NG opens up a new approach for high-performance on-body biomechanical energy harvesting as renewable and sustainable power sources for wearable electronics. [ABSTRACT FROM AUTHOR]

Recently, flexible thermoelectric (TE) generators (f-TEGs) have received a lot of attention. Compared with TE films on flexible substrates, self-supporting composite films prepared by combining TE materials with soft fabrics and thus retaining the inherent advantages of fabrics, such as stretchability, breathability, and flexibility, are more practical and may significantly expand the application of f-TEGs in smart wearable devices. Hence, in this work, a facile and rapid method for preparing ultra-flexible self-supporting Ag 2 Se/nylon composite films is developed. The composite films with both TE properties and flexibility were obtained by fast selenization of commercial Ag/nylon fiber fabrics in a short time (60 s) at room temperature and then hot pressing at 230 °C in a vacuum. The maximum power factor of an optimized composite film at room temperature can reach 73.7 μW m−1 K−2. Meanwhile, the film exhibits excellent flexibility with the Seebeck coefficient and electrical conductivity decreased by only 7.37 and 8.48% after being bent 4000 repetitions around a round bar with a radius of 4 mm, which exceeds most reported flexible TE films. The ultra-high flexibility is mainly attributed to its high content of the nylon matrix (∼85.05 wt%), the tight bonding between Ag 2 Se grains, and the good combination between the Ag 2 Se and nylon matrix. In addition, a 3-leg f-TEG assembled with the optimal film produces a maximum power of ∼1.524 μW (corresponding to a power density of ∼0.47 W m−2) at a temperature gradient of 40.6 K, verifying the good TE performance of the composite film. This f-TEG can also be used as a self-powered temperature sensor, showing potential applications in daily life. • Self-supporting Ag 2 Se/nylon composite films were prepared by a novel method. • The composite film is ultra-flexible mainly due to high content of nylon. • An optimized film shows a power factor of 73.7 μW m−1 K−2 at room temperature. • A flexible thermoelectric generator was assembled with the optimal film. • The generator exhibits high output performance near room temperature. [ABSTRACT FROM AUTHOR]

Copper-sulfide-based materials have attracted noteworthy attention as thermoelectric materials due to rich elemental reserves, non-toxicity, low thermal conductivity, and adjustable electrical properties. However, research on the flexible thermoelectrics of copper sulfide has not yet been reported. In this work, we developed a facile method to prepare flexible Mn-doped Cu2−xS films on nylon membranes. First, nano to submicron powders with nominal compositions of Cu2−xMnyS (y = 0, 0.01, 0.03, 0.05, 0.07) were synthesized by a hydrothermal method. Then, the powders were vacuum-filtrated on nylon membranes and finally hot-pressed. Phase composition and microstructure analysis revealed that the films contained both Cu2S and Cu1.96S, and the size of the grains was ~20–300 nm. By Mn doping, there was an increase in carrier concentration and mobility, and ultimately, the electrical properties of Cu2−xS were improved. Eventually, the Cu2−xMn0.05S film showed a maximum power factor of 113.3 μW m−1 K−2 and good flexibility at room temperature. Moreover, an assembled four-leg flexible thermoelectric generator produced a maximum power of 249.48 nW (corresponding power density ~1.23 W m−2) at a temperature difference of 30.1 K, and had good potential for powering low-power-consumption wearable electronics. [ABSTRACT FROM AUTHOR]

Objective To describe the occurrence of general surgical complications and establish prediction models for different types of complications based on a multicenter cohort study. Methods Based on Modern Surgery and Anesthesia Safety Management System Construction and Promotion(MSCP), patients who underwent general surgery in 4 hospitals from January to June 2015 and from January to June 2016 were selected as participants, and perioperative data of patients were collected. Logistic regression was used to identify risk factors and predict complications. Results Among 19 223 patients, 830(4.32%) had complications. Among participants who had complications, 371(44.70%) had incision complications, 190(22.89%) had fistula complications, 310(37.35%) had infection complications, 161(19.40%) had failure complications, and 104(12.5%) died. There were significant differences in the risk factors of different types of complications. The risk factors of incision,infection and failure covered the whole perioperative period, while fistula complications mainly focused on the difficulty of surgery and postoperative treatment, and for death outcomes, postoperative risk factors were more severe than preoperative risk factors. The areas under the curves of prediction were between 0.80-0.93. Conclusions In general surgery, different types of complications have different risk factors. The targeted prediction model can avoid the rough simplification of complications and fuzzy influence of each factor, and can provide reference for the prevention of complications.

As a vital parameter in living cells and tissues, the micro-environment is crucial for the living organisms. Significantly, organelles require proper micro-environment to achieve normal physiological processes, and the micro-environment in organelles can reflect the state of organelles in living cells. Moreover, some abnormal micro-environments in organelles are closely related to organelle dysfunction and disease development. So, visualizing and monitoring the variation of micro-environments in organelles is helpful for physiologists and pathologists to study the mechanisms of the relative diseases. Recently, a large variety of fluorescent probes was developed to study the micro-environments in living cells and tissues. However, the systematic and comprehensive reviews on the organelle micro-environment in living cells and tissues have rarely been published, which may hinder the research progress in the field of organic fluorescent probes. In this review, we will summarize the organic fluorescent probes for monitoring the microenvironment, such as viscosity, pH values, polarity, and temperature. Further, diverse organelles (mitochondria, lysosome, endoplasmic reticulum, cell membrane) about microenvironments will be displayed. In this process, the fluorescent probes about the "off-on" and ratiometric category (the diverse fluorescence emission) will be discussed. Moreover, the molecular designing, chemical synthesis, fluorescent mechanism, and the bio-applications of these organic fluorescent probes in cells and tissues will also be discussed. Significantly, the merits and defects of current microenvironment-sensitive probes are outlined and discussed, and the development tendency and challenges for this kind of probe are presented. In brief, this review mainly summarizes some typical examples and highlights the progress of organic fluorescent probes for monitoring micro-environments in living cells and tissues in recent research. We anticipate that this review will deepen the understanding of microenvironment in cells and tissues and facilitate the studies and development of physiology and pathology. [ABSTRACT FROM AUTHOR]

Thermally activated delayed fluorescence (TADF) materials have been regarded as promising host materials for fluorescent and phosphorescent guest materials to achieve high performance organic light-emitting diodes (OLEDs). In this work, three molecules, PhCQ , m -PyCQ and p -PyCQ, using carbazole derivatives as donor and quinazoline units as acceptor were designed and synthesized. Both theoretical and experimental results showed that PhCQ , m -PyCQ and p -PyCQ possess TADF properties with higher triplet excited states than red phosphorescent guest, RD-1. When used as host materials for RD-1, it was found that the emission spectrum of PhCQ has the largest overlap with the absorption spectrum of RD-1, which is conducive to Förster resonance energy transfer (FRET) between the host to the guest. As a result, red phosphorescent OLED device based on PhCQ host exhibited the best performances with the maximum external quantum efficiency (EQE) of 37.2 %. When the brightness is 1000 cd/m2, the EQE is still as high as 33.0 %. [Display omitted] • Three TADF host materials, PhCQ , m -PyCQ and p -PyCQ, for red PhOLEDs were designed and synthesized. • Carbazole and quinazoline derivatives were employed to balance the carrier transport. • The maximum external quantum efficiency of the top-emitting device based on PhCQ was 37.16 %. [ABSTRACT FROM AUTHOR]

Flexible thermoelectric (TE) generators (f-TEGs) are promising candidates to power explosively growing wearable electronics by continually converting body heat into electricity. However, intrinsic brittleness, unscalability, and high costs hinder high-performance bulk TE materials from application as f-TEGs. Herein, we report a flexible and self-healable Ag 2 Se/terpineol composite film on a nylon membrane prepared by first one-pot synthesis of Ag 2 Se powder, then screen-printing, and finally low-temperature (473 K) heat treatment. Microstructure observations reveal that the film is dense and that it consists of nano to micron Ag 2 Se grains with coherent- and semicoherent grain boundaries and a very small amount of terpineol at nanopores and/or grain boundaries. Because of the unique microstructure and synergistic effect of the two components, an optimal film exhibits a high power factor of 1550 μW m−1 K−2 (corresponding zT ∼ 0.8) at room temperature and good mechanical properties (flexibility, anti-tensile property, and self-healing ability). A six-leg f-TEG assembled with the film shows a power density of 16.23 W m−2 at a temperature difference of 34.1 K and excellent flexibility. • Ag 2 Se/terpineol nanocomposite films were prepared by a screen-printing technique. • An optimal film exhibits a power factor of 1550 μW m−1 K−2 at room temperature. • The film possesses good flexibility, anti-tensile property, and self-healing ability. • A six-leg f-TEG assembled shows a high output property and excellent flexibility. [ABSTRACT FROM AUTHOR]

N-type Ag 2 Se/PVP composite film on nylon membrane with ultrahigh thermoelectric performance and excellent flexibility. [Display omitted] • Ag nanoparticle decorated Ag 2 Se nanostructures coated with PVP are prepared. • Ag 2 Se/PVP composite films are formed by vacuum filtration and then hot pressing. • An optimal film shows ultrahigh thermoelectric power factor and flexibility. • A thermoelectric generator is assembled using the optimal flexible film. • The generator exhibits an excellent output performance. Flexible thermoelectric (TE) generators (F-TEGs), able to harvest heat energy from the human body, are considered to be competitive energy supply devices for wearable and implantable electronics. Herein, we fabricate Ag 2 Se/polyvinylpyrrolidone (PVP) films on nylon membranes via a novel nanoengineering approach: First, small amount Ag nanoparticles decorated Ag 2 Se nanowires (NWs) coated with a nanolayer of PVP are synthesized via a Se NW template method, and the Ag nanoparticles react with small amount Se residues at the core of the Ag 2 Se NWs during hot-pressing and form Ag 2 Se nanograins rich in defects embedded in big Ag 2 Se grains. The Ag 2 Se nanograin has a different orientation from the big Ag 2 Se grain; hence, the interface between the Ag 2 Se nanograin and the big Ag 2 Se grain enhances the phonon scattering but almost does not affect the transport of carriers. An optimized film exhibits a maximum power factor of 2478 ± 67 μW m−1 K−2 (corresponding ZT ∼ 1.05) at 300 K, which is one of the highest values reported for flexible Ag 2 Se films. The excellent TE properties of the film are attributed to its unique microstructure: highly densified, coherent/semi-coherent Ag 2 Se grains, embedded Ag 2 Se nanograins, and a very small amount of PVP located at nanopores. Besides, the film shows good flexibility: after 1500 times bending along a rod with a radius of 4.0 mm, the electrical conductivity still maintains 90.9 %. Furthermore, a 6-leg F-TEG assembled with the optimal film generates a maximum power of 4.58 μW (corresponding power density of ∼ 31.2 W m−2) at a temperature gradient of 38.7 K. This work provides an efficient strategy for the fabrication of ultrahigh-performance Ag 2 Se-based flexible TE films. [ABSTRACT FROM AUTHOR]

[Display omitted] • TADF hosts based on nonbenzenoid aromatic aza-azulene were synthesized. • The k RISC of 9.0 × 106 s−1 was obtained induced by aromaticity and geometry vibration. • Enhanced intra/inter-molecular interaction promotes electron coupling. • Red PhOLED with EQE > 50 % and LT 95 = 52,350 h was accessed. The fast triplet-singlet up-conversion based on thermally activated delayed fluorescence (TADF) molecules is a unique effort to improve the utilization of triplet excitons. We construct two TADF molecules using nonbenzenoid aromatic aza-azulene as donor and triazine as acceptor. The distortion structural resonance of aza-azulene enhances the reverse intersystem crossing (RISC) process, resulting in efficient inter/intramolecular charge transfer (CT) emission. The rate constant of RISC (k RISC) is 9.0 × 106 and 8.4 × 106 s−1 in solid states. Efficient Förster Energy Transfer (FRET) and/or Dexter Energy Transfer (DET) between these molecules and dopants make them suitable host materials to improve the performances of red phosphorescent organic light-emitting diodes (OLEDs). Especially, the top-emitting device achieves an external quantum efficiency (EQE) of 51.3% and a current efficiency of 68.2 cd/A at 1000 cd m−2 with a long device lifetime of LT 95 = 52,350 and LT 50 = 536,200 h. [ABSTRACT FROM AUTHOR]

[Display omitted] • A nationwide spatial analysis on surface water pollutants and cancers integrating datasets was conducted. • Geographically weighted random forest addressed spatial heterogeneity for surface water pollutants. • Multiple pollutants of surface water spatially associated with digestive cancer incidence in China. Surface water pollution and digestive cancers are concerning environmental health issues. Multiple pollutants of surface water coexist within unique geospatial heterogeneous contexts of surface water flow, which can lead to complex patterns of impact on cancer incidence. This complexity has posed challenges to comprehensive assessment. In this study, we integrated nationwide surface water data of 21 pollutants collected from 3632 sections of nine large river basins and cancer incidence data for six digestive cancers covering 381.6 million people in China. Local Moran's I method was used to assess the patterns of spatial aggregation of each surface water pollutant separately to observe the local spatial nonstationarity and heterogeneity of the pollutant concentrations in different spatial areas. A geographically weighted random forest (GWRF) model, a spatial machine learning approach, was applied to address the spatial heterogeneity of the pollutants and assess their association with cancer incidence. Goodness-of-fit and overall performance of the GWRF model were assessed by the local statistics in the out-of-bag set, such as the mean local pseudo-R2, increase in mean squared error, and local residuals in each local model. Compared with the aspatial random forest model, the GWRF model had better performance (mean local pseudo-R2 ranged from 0.16 (gallbladder cancer) to 0.60 (pancreatic cancer)). Surface water pollution was associated with digestive cancer incidence mainly in the Songhua and Liaohe, Haihe, and Huaihe River Basins. By focusing on these areas, we identified key pollutants specific to different cancer types. Incidence of oesophageal, stomach, colorectal, gallbladder, and pancreatic cancer was associated with common pollutants such as fluoride and arsenic. Our assessment provides targets for the government and environmental health specialists to take tailored actions to control pollution and effectively prevent cancer incidence. [ABSTRACT FROM AUTHOR]

• The present network visualized the complex associations among multiple complications. • Our new grading approach can classify complication severity using the items. • Quantified associations among complications included cascade, cluster, and synergy. • Updating probability with new information supports prevention and clinical decision. Postoperative complications confer an increased risk of reoperation, prolonged length of hospital stay, and increased mortality. Many studies have attempted to identify the complex associations among complications to preemptively interrupt their progression, but few studies have looked at complications as a whole to reveal and quantify their possible trajectories of progression. The main objective of this study was to construct and quantify the association network among multiple postoperative complications from a comprehensive perspective to elucidate the possible evolution trajectories. In this study, a Bayesian network model was proposed to analyze the associations among 15 complications. Prior evidence and score-based hill-climbing algorithms were used to build the structure. The severity of complications was graded according to their connection to death, with the association between them quantified using conditional probabilities. The data of surgical inpatients used in this study were collected from four regionally representative academic/teaching hospitals in a prospective cohort study in China. In the network obtained, 15 nodes represented complications or death, and 35 arcs with arrows represented the directly dependent relationship between them. With three grades classified on that basis, the correlation coefficients of complications within grades increased with increased grade, ranging from −0.11 to −0.06, 0.16, and 0.21 to 0.4 in grade 1 to grade 3, respectively. Moreover, the probability of each complication in the network increased with the occurrence of any other complication, even mild complications. Most seriously, once cardiac arrest requiring cardiopulmonary resuscitation occurs, the probability of death will be up to 88.1%. The present evolving network can facilitate the identification of strong associations among specific complications and provides a basis for the development of targeted measures to prevent further deterioration in high-risk patients. [ABSTRACT FROM AUTHOR]