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Modeling of chemical-looping combustion process of methane with nickel-based oxygen carrier

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Abstract

The chemical-looping combustion of methane in a three-dimensional cylindrical fuel reactor is numerically studied using the developed multiphase particle-in-cell reactive model, featuring the multi-phase flow, heat transfer, reduction of oxygen carriers, and particle shrinkage. After model validation, the general flow patterns, and the thermophysical properties of oxygen carriers (e.g., temperature, heat transfer coefficient) and gas phase (e.g., temperature, density, thermal conductivity, specific heat capacity, and viscosity) are comprehensively studied with the discussion on several crucial operating parameters. The results show that bubble dynamics (e.g., generation, rising, coalescence, and eruption) induce the segregation of small- and large-mass particles. CH4 is thoroughly converted in a very short distance above the bottom distributor while CO and H2 increase above the bottom distributor and then decrease axially. The temperature of particles ranges from 1275 to 1295 K, leading to a 20 K temperature difference in the bed. The heat transfer coefficient (HTC) of particles is in the range of 50–150 W/(m2·K). Increasing the investigated operating parameters (i.e., superficial gas velocity, methane ratio, and wall temperature) enlarges the particle properties (i.e., temperature, HTC) and most of the gas properties (i.e., temperature, thermal conductivity, specific capacity, and viscosity), but decreases the gas density. The findings shed light on the reactor design and process control of the chemical-looping combustion systems.


Retraction Note: Man–machine dialogue system optimization based on cloud computing

CF-DAN: Facial-expression recognition based on cross-fusion dual-attention network

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Abstract

Recently, facial-expression recognition (FER) has primarily focused on images in the wild, including factors such as face occlusion and image blurring, rather than laboratory images. Complex field environments have introduced new challenges to FER. To address these challenges, this study proposes a cross-fusion dual-attention network. The network comprises three parts: (1) a cross-fusion grouped dual-attention mechanism to refine local features and obtain global information; (2) a proposed C2 activation function construction method, which is a piecewise cubic polynomial with three degrees of freedom, requiring less computation with improved flexibility and recognition abilities, which can better address slow running speeds and neuron inactivation problems; and (3) a closed-loop operation between the self-attention distillation process and residual connections to suppress redundant information and improve the generalization ability of the model. The recognition accuracies on the RAF-DB, FERPlus, and AffectNet datasets were 92.78%, 92.02%, and 63.58%, respectively. Experiments show that this model can provide more effective solutions for FER tasks.

Enhanced Redox Ability of LaCoO3 Catalysts by Cu Doping in Methane Combustion

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Abstract

CH4 combustion is one of the effective ways to reduce atmospheric lean CH4. Herein, a series of La-Co-Cu-O catalysts were successfully prepared by sol–gel method and applied to CH4 combustion. The doping of Cu could improve the catalytic activity of LaCoO3 catalyst. Among the samples, La0.85Cu0.15CoO3 and LaCu0.15Co0.85O3 with the same Cu doping amount exhibited better catalytic performance. Compared with LaCu0.15Co0.85O3, La0.85Cu0.15CoO3 catalyst with better redox ability and stronger adsorption capacity for CH4 and O2, exhibited higher reactivity in CH4 combustion. It was proposed that the coexistence of exposed dispersed Co3O4 particles and Cu ions in the system of La0.85Cu0.15CoO3 could lead to relatively better redox ability and stronger adsorption capacity for CH4 combustion. The La0.85Cu0.15CoO3 is proved to be an extremely valuable and potential catalyst for CH4 combustion.

Graphical abstract

Multigenerational paternal obesity enhances the susceptibility to male subfertility in offspring via Wt1 N6-methyladenosine modification

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Abstract

There is strong evidence that obesity is a risk factor for poor semen quality. However, the effects of multigenerational paternal obesity on the susceptibility to cadmium (a reproductive toxicant)-induced spermatogenesis disorders in offspring remain unknown. Here, we show that, in mice, spermatogenesis and retinoic acid levels become progressively lower as the number of generations exposed to a high-fat diet increase. Furthermore, exposing several generations of mice to a high fat diet results in a decrease in the expression of Wt1, a transcription factor upstream of the enzymes that synthesize retinoic acid. These effects can be rescued by injecting adeno-associated virus 9-Wt1 into the mouse testes of the offspring. Additionally, multigenerational paternal high-fat diet progressively increases METTL3 and Wt1 N6-methyladenosine levels in the testes of offspring mice. Mechanistically, treating the fathers with STM2457, a METTL3 inhibitor, restores obesity-reduced sperm count, and decreases Wt1 N6-methyladenosine level in the mouse testes of the offspring. A case-controlled study shows that human donors who are overweight or obese exhibit elevated N6-methyladenosine levels in sperm and decreased sperm concentration. Collectively, these results indicate that multigenerational paternal obesity enhances the susceptibility of the offspring to spermatogenesis disorders by increasing METTL3-mediated Wt1 N6-methyladenosine modification.

Mixing enhancement of solid-liquid two-phase by coupling double-layer rigid impeller and non-constant chaotic rotating speed

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Abstract

Efficient mixing in stirred tanks could be achieved in the presence of isolated mixing regions using a controlled fluctuation of the impeller rotation rate. In this paper, nine rigid impellers with double-layer were used under two various stirring modes including constant and chaotic speeds to compare and investigate the solid–liquid two-phase (i.e., polyformaldehyde–glycerol) mixing systems. Results show that the chaos degree of the mixing system was the highest with the Kolmogorov entropy of 0.1818, the largest Lyapunov exponent of 0.2263, and the 0–1 test indicator of 0.8134 when the upper and lower double-layer impellers with circular three-blade were used for unidirectional chaotic speed stirring at speed peak of 200 r/min and speed change interval of 5 s. The mixing performance of solid–liquid two-phase mixing system was the best with the mixing time of 14 s and the mixing energy consumption of 99.04 J while the upper and lower impellers were both with round four-blade. Chaotic rotational speed stirring consumes less power per unit time under the same working condition, but its energy saving was still not enough to eliminate the influence caused by the long mixing time. It is found that the disturbances below a certain amount have a weak effect on the mixing performance although the chaotic motor could generate stronger dynamic disturbances and is more likely to cause chaotic mixing. Furthermore, the speed change times decreased, and the velocity gradient in the flow field decrease accordingly while the speed change time of chaotic speed stirring was too long. To sum up, it maybe that the mixing performance of the solid–liquid mixing system under unidirectional chaotic speed stirring is not as good as that under constant speed stirring on this condition, which is the main merit of this work.

Prevalence and causes of blindness and distance visual impairment in Chinese adult population in 2022 during the COVID-19 pandemic: a cross-sectional study

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Abstract

This cross-sectional study aims to investigate the prevalence and causes of visual impairment (VI) and blindness in Jiangsu Province, China in 2022 during the COVID-19 pandemic. Participants (n = 13,208, aged 18–93) underwent comprehensive ocular examinations. The prevalence and causes of binocular VI (presenting visual acuity [VA] ≥ 20/400 and < 20/63 in the better eye) and blindness (presenting VA < 20/400 in the better eye) were assessed according to the World Health Organization (WHO) criteria. The estimation of refractive error prevalence was conducted using the following classification: myopia ≤  − 0.50 diopters (D), high myopia ≤  − 6.00 D, hyperopia ≥ 0.50 D, and anisometropia ≥ 1.00 D. The overall prevalence of binocular VI and blindness was 21.04% (95% confidence interval [CI] 20.35–21.74%) and 0.47% (95% CI 0.37–0.60%). The highest prevalence of binocular VI was in the population aged 18–24 years old (46.29%, [95% CI 44.30–48.28%]), those with education at university and above (43.47%, [95% CI 41.93–45.02%]), students (54.96%, [95% CI 52.73–57.17%]). Uncorrected refractive error (URE) was the leading cause of presenting binocular VI (93.40%) and blindness (50.79%). The prevalence of myopia was 54.75% (95% CI 53.90–55.60%). Actions are needed to control URE and myopia within the adult Chinese population, with a particular emphasis on the younger, well-educated demographic.

The first case report: diagnosis and management of necrotizing fusobacterium lung abscess via BALF next-generation sequencing

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Abstract

Background

Fusobacterium necrophorum (F. necrophorum)-induced necrotizing pneumonia is a rare but severe pulmonary infection. Insufficient microbiological detection methods can lead to diagnostic difficulties.

Methods

We report a case of F. necrophorum lung abscess diagnosed by next-generation sequencing (NGS) of bronchoalveolar lavage fluid (BALF).

Results

BALF-NGS detected F. necrophorum, guiding subsequent targeted antibiotic therapy. With active drainage and metronidazole treatment, the patient’s condition was effectively treated.

Conclusion

BALF-NGS is a valuable tool for the rapid diagnosis of infections caused by difficult-to-culture bacteria. It played a decisive role in the early identification of F. necrophorum, enabling timely and targeted antibiotic intervention. Early diagnosis and appropriate treatment are crucial for the management of F. necrophorum pneumonia.


Size-Dependent Elastic Properties of Nanofilms: Exponentially Decreased Surface Elasticity Model

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Abstract

In this work, we propose a continuum theoretical model to describe the surface-modulated and size-dependent elastic properties of nanofilms. The influence of surface Young’s modulus (surface biaxial modulus) decreases with increasing the distance from the film surface. The decrease law is assumed as exponential in this work. In core-surface and core-shell models, an imaginary interface between the surface area and bulk-like inner core appears. Since the influence of surface elasticity decreases with the distance from the surface layer continually, the interface is non-existent and non-physical. The present theoretical model eliminates the interface and is proved to be a veritable continuum theory. There is no concept of “bulk-like core area” and “surface area” in current theory. The existence of surface Young’s modulus decrease introduces second and third surface modifications. When the influence of surface Young’s modulus decreases rapidly, i.e. the decrease factor α → ∞, the influence of surface Young’s modulus only works near the surface. And then, the current theory will degenerate into a core-surface one. The current theory is used to describe the size-dependent biaxial modulus of Si, diamond, Au and Cu nanofilms. The theoretical prediction gives good agreement with simulated results of these nanofilms. The present study in this paper is envisaged to provide useful insights for the design and application of nanofilm-based devices.

A metagenomic catalog of the early-life human gut virome

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Abstract

Early-life human gut microbiome is a pivotal driver of gut homeostasis and infant health. However, the viral component (known as “virome”) remains mostly unexplored. Here, we establish the Early-Life Gut Virome (ELGV), a catalog of 160,478 non-redundant DNA and RNA viral sequences from 8130 gut virus-like particles (VLPs) enriched or bulk metagenomes in the first three years of life. By clustering, 82,141 viral species are identified, 68.3% of which are absent in existing databases built mainly from adults, and 64 and 8 viral species based on VLPs-enriched and bulk metagenomes, respectively, exhibit potentials as biomarkers to distinguish infants from adults. With the largest longitudinal population of infants profiled by either VLPs-enriched or bulk metagenomic sequencing, we track the inherent instability and temporal development of the early-life human gut virome, and identify differential viruses associated with multiple clinical factors. The mother-infant shared virome and interactions between gut virome and bacteriome early in life are further expanded. Together, the ELGV catalog provides the most comprehensive and complete metagenomic blueprint of the early-life human gut virome, facilitating the discovery of pediatric disease-virome associations in future.

La2O3-Doped (K0.5Na0.5)NbO3-Based Photochromic Transparent Ceramics for Optical Storage Applications

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Abstract

Good transparency and color contrast are difficult to obtain at the same time, which is a pressing problem for photochromic ceramics. Lanthanum oxide doping improved the transmittance and color-changing characteristics of the sample. In this study, the photochromism and reversible luminescence modulation of 0.94(K0.5Na0.5)NbO3-0.06Sr(Bi0.5Nb0.5)O3:2.0 wt% La3+ (KNN–SBN + La2.0) transparent ferroelectric ceramics with different sintering temperatures were investigated. KNN–SBN + La2.0 has good light transmittance and color contrast characteristics, as well as a certain degree of photoluminescence characteristics. The sample that was sintered at 1162°C has a relatively high dielectric constant (εr) and a high transmittance (1100 nm). The diffuse reflection spectra of the sample that was sintered at 1182°C has a wide absorption band at 400 nm, while, after ultraviolet irradiation, the reflectivity of the sample is significantly reduced. The color rendering rate of the sample at the sintering temperature of 1182°C is high, the color rendering contrast (ΔRT) is 60.01%, and the high fluorescence luminescence contrast (ΔRI) is 82.42% under 150 s of 365-nm light. Based on these results, KNN–SBN + La2.0 ceramics have a good application prospect in data storage and electronic goods.

Triple reverse order law for the Drazin inverse

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Abstract

In this paper, we investigate the reverse order law for Drazin inverse of three bounded linear operators under some commutation relations. Moreover, the Drazin invertibility of sum is also obtained for two bounded linear operators and its expression is presented.

Donor–acceptor covalent organic frameworks-confined ultrafine bimetallic Pt-based nanoclusters for enhanced photocatalytic H2 generation

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Abstract

Photocatalytic hydrogen generation from hydrogen storage media is an effective and promising approach for the green hydrogen industry as well as for achieving carbon neutrality goals. However, the lower photocatalytic efficiency due to the limited light trapping capacity, low electron transfer rate, and severe aggregation of nanoparticles caused by high surface energy seriously restricts their practical application. Herein, we constructed a series of donor–acceptor (D–A) type covalent organic frameworks to confine ultrafine bimetallic Pt-based nanoclusters for photocatalytic hydrogen generation from ammonia borane (AB) hydrolysis. Under visible light irradiation at 20 °C, PtCo2@covalent organic framework (COF) showed the highest photocatalytic activity with a turnover frequency (TOF) of 486 min−1. Experiments and density functional theory (DFT) calculations reveal that the high catalytic activity is mainly attributed to the strong electronic interactions between D–A type COF and ultrafine PtCo2 nanoclusters. Specifically, the D–A type COF can significantly enhance the light-trapping ability by fine-tuning the electron-acceptor type in the framework, and accelerate the photogenerated electron transfer from D–A type COF to PtCo2 nanocluster, which promotes the adsorption and activation of H2O and AB molecules and accelerates hydrogen release. Furthermore, PtCo2@COF also exhibited ultra-high durability due to the significantly enhanced resistance to nanocluster aggregation caused by the nanopore confinement effect of D–A type COF. We believe that this work will provide a theoretical guide for the rational design of efficient D–A COF-based catalysts for photocatalysis.

Optimization of wideband RCS reduction via controlled phase and amplitude in metasurface design

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Abstract

In this study, we introduce a strategy for constructing an absorptive metasurface, which integrates the absorption and phase cancellation mechanisms. Through topological optimization and the synthesis of a checkerboard metasurface array, we achieve a significant reduction in ultra-wideband RCS. A prototype of the suggested design is produced and tested to confirm the effectiveness of the absorptive coding metasurface. When compared to a metallic plate of the same dimensions, a notable decrease in reflection is observed within the 4.0–12.0 GHz range. The RCS reduction exceeds 15 dB within the same frequency range (the fractional bandwidth is 100%). The proposed methods of phase and amplitude control, along with topological optimization, prove to be efficient strategies for wideband RCS reduction applications.

Petrogenesis, oxidation state and volatile content of Dongga tonalite in the Gangdese belt, Xizang: Implication for porphyry Cu mineralization

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Abstract

The Gangdese belt in Xizang has experienced both Jurassic subduction and Cenozoic continental collision processes, making it a globally renowned region for magmatic rocks and porphyry copper deposits. Numerous Jurassic intrusions have been identified in the belt. Apart from the quartz diorite porphyry in the large Xietongmen deposit, the Cu mineralization potential of other Jurassic intrusions in this belt remains unclear. This study presents zircon U–Pb dating and trace elements, apatite major and trace elements as well as published whole-rock geochemical and isotopic data of the Dongga tonalite in the central part of the Gangdese belt, aiming to reveal the petrogenesis, oxidation state, volatile content, and Cu mineralization potential of this intrusion. The Dongga tonalite has a zircon U–Pb age of 179.4 ± 0.9 Ma. It exhibits high whole-rock V/Sc values (8.76–14.6), relatively low apatite CeN/CeN* ratios (1.04–1.28), elevated zircon (Eu/Eu*)N values (an average of 0.44), high Ce4+/Ce3+ values (205–1896), and high ∆FMQ values (1.3–3.7), collectively suggesting a high magmatic oxygen fugacity. The Dongga tonalite features amphibole phenocrysts, relatively high whole-rock Sr/Y ratios (20.3–58.9), and lower zircon Ti temperatures (502–740 °C), reflecting a high magmatic water content. Estimation of magmatic sulfur content (0.002–0.024 wt%) based on apatite SO3 contents indicates an enriched magma sulfur content. Combined with previous studies and the collected Sr–Nd–Hf isotopes, the Dongga tonalite is derived from juvenile lower crust related with subduction of the NeoTethys oceanic slab. When compared with Xietongmen ore-bearing porphyries, the Dongga tonalite exhibits remarkable similarities with the Xietongmen ore-bearing porphyries in terms of magma source, tectonic background, magmatic redox state, and volatile components, which indicates that the Dongga tonalite has a high porphyry Cu mineralization potential, and therefore, provides important guidance for the future mineralization exploration.


Neutrophils in cancer: dual roles through intercellular interactions

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Abstract

Neutrophils, the most abundant immune cells in human blood, play crucial and diverse roles in tumor development. In the tumor microenvironment (TME), cancer cells regulate the recruitment and behaviors of neutrophils, transforming some of them into a pro-tumor phenotype. Pro-tumor neutrophils interact with cancer cells in various ways to promote cancer initiation, growth, and metastasis, while anti-tumor neutrophils interact with cancer cells to induce senescence and death. Neutrophils can also interact with other cells in TME, including T cells, macrophages, stromal cells, etc. to exert anti- or pro-tumor functions. In this review, we will analyze the anti- and pro-tumor intercellular interactions mediated by neutrophils, with a focus on generalizing the mechanisms underlying the interaction of neutrophils with tumor cells and T cells. Furthermore, we will provide an overview of cancer treatment strategies targeting neutrophil-mediated cellular interactions.

Inertia in cognitive processes: the case of the COVID-19 vaccine

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Abstract

Developments in factor analysis (Spearman in Am J Psychol 15:201-292, 1904); Thurstone in Multiple factor analysis, University of Chicago Press, Chicago, 1947), multidimensional scaling (Torgerson in Theory and methods of scaling, Wiley Hoboken, New Jersey, 1958; Young and Householder in Psychometrika, 3:19–22, 1938), the Galileo model (Woelfel and Fink in The measurement of communication processes: galileo theory and method, Academic Press Cambridge, Massachusetts, 1980), and, more recently, in computer science, artificial intelligence, computational linguistics, network analysis and other disciplines (Woelfel in Qual Quant 54:263–278, 2020) have shown that human cognitive and cultural beliefs and attitudes can be modeled as movement through a high-dimensional non-Euclidean space. This article demonstrates the theoretical and methodological contribution that multidimensional scaling makes to understand attitude change associated with the COVID-19 vaccine.

Facile and effective synthesis strategy for terbium-doped hydroxyapatite toward photoelectric devices and flexible functional fibers

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Abstract

As a material with good biocompatibility, hydroxyapatite (HAP) can have optical properties after doping with various rare earth ions. As a biocompatible fluorescent material, doped HAP could have broad applications in biological probes, drug delivery, optoelectronic materials, fluorescence anti-counterfeiting, and other aspects. In this paper, we put forward the preparation of HAP doped with terbium (III) ions (Tb3+) by hydrothermal co-precipitation. By controlling the Tb3+ doping content in reaction and the reaction time, the changes in HAP’s structure, morphology, and luminescence properties under different conditions were studied. When the doping amount of Tb3+ reached an optimal value, the dipole-quadrupole would occur and the concentration would be quenched. The control experiment showed that the optimal Tb3+ content was 7.5 × 10–5 mol, which showed the best fluorescence performance. HAP, a non-luminous material, was rarely used in the field of fluorescent anti-counterfeiting and photoelectric devices. We proposed to prepare a luminescent aramid/polyphenylene sulfide (ACFs/PPS) fiber paper and a new light-emitting diode (LED) using the Tb-doped HAP phosphor. The composite sample exhibited an excellent stability and fluorescence performance, which also demonstrated a possibility of HAP applications in anti-counterfeiting and photoelectric. The introduction of Tb3+ dopant HAP was done to give HAP optical properties and broaden the application range of HAP.

Graphical abstract

Advances in epigenetic alterations of chronic lymphocytic leukemia: from pathogenesis to treatment

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Abstract

Chronic lymphocytic leukemia (CLL) is a heterogeneous disease with alterations in genetic expression and epigenetic modifications. In recent years, the new insight into epigenetics in the pathogenesis of CLL has been developed considerably, including DNA methylation, histone modification, RNA methylation, non-coding RNAs as well as chromatin remodeling. Epigenetic modification regulates various processes such as stem cell biology, cell growth, and tumorigenesis without altering gene sequence. Growing evidence indicates that the disturbance of gene expression profiles which were regulated by epigenetic modifications exerts vital roles in the development and progress in CLL, which provides novel perspectives to explore the etiology of CLL. In addition, the integration with epigenetic therapeutic targets and the in-depth understanding of epigenetic therapy contribute to develop new therapeutic strategies for CLL. Herein, the present review discusses the advances of epigenetic alterations in the pathogenesis, diagnosis, and prognostic assessment of CLL patients and also highlights existing and emerging agents targeting epigenetic regulators.

Predictive value of the Adult Comorbidity Evaluation 27 on adverse surgical outcomes and survival in elderly with advanced epithelial ovarian cancer undergoing cytoreductive surgery

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Abstract

Objective

We aimed to evaluate the ability of Adult Comorbidity Evaluation 27 (ACE-27) to predict perioperative outcomes and survival in elderly women with advanced epithelial ovarian cancer (AEOC) undergoing cytoreductive surgery.

Methods

We collected patients with AEOC in our hospital between January 1, 2012 and January 1, 2021. Patients younger than 65 years old or those with non-epithelial ovarian cancer were excluded. ACE-27 was applied retrospectively to assess comorbidities in the selected patients, who were then classified into two groups based on their ACE-27 scores: low ACE-27 score group (none to mild) and high ACE-27 score group (moderate to severe).

Results

A total of 222 elderly women with AEOC were included, of whom 164 patients accepted debulking surgery. Among those who have undergone surgery, Clavien–Dindo grade III + perioperative complications or unintended intensive care unit (ICU) admission occurred more often in patients of high ACE-27 score group, with statistically significant difference (odds ratio [OR]: 4.21, 95% confidence interval [CI], 1.28–14.35, p = 0.018). Further stratified analyses by age, BMI, FIGO stage and pathology also prove that OS of patients graded severe was shorter than patients graded none to moderate in cohort of age < 70, BMI < 25 kg/m2, FIGO III stage and pathology of serous, respectively. Kaplan–Meier survival curves analyzed by log-rank test showed that the overall survival (OS) of patients with severe comorbidities were shorter than with none to moderate (HR 3.25, 95%CI 1.55–6.79, p = 0.002).

Conclusions

Our findings demonstrate the ability of ACE-27 to predict grade III + perioperative complications or unintended ICU admission and survival in elderly patients with AEOC. This highlights the possibility for ACE-27 to play an instrumental role in identifying AEOC patients who are more susceptible to adverse surgical outcomes and have a poor survival rate and assisting in decisions regarding treatment.





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