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• Aim to identify independent risk factors for postoperative delirium after pituitary adenoma surgery. • Select matched subjects by Propensity Score Matching to reduce potential biases caused by variables. • Enhance preoperative communication to minimize the occurrence of delirium, for patients at high risk of postoperative delirium. • Minimize surgery duration and general anesthesia, optimize perioperative sedation regimen. • Reducing unnecessary or excessive protective physical restraints. The primary aim of this study is to explore the factors associated with delirium incidence in postoperative patients who have undergone endoscopic transsphenoidal approach surgery for pituitary adenoma. The study population included patients admitted to Tianjin Huanhu Hospital's Skull Base Endoscopy Center from January to December 2022, selected through a retrospective cohort study design. The presence of perioperative delirium was evaluated using the 4 'A's Test (4AT) scale, and the final diagnosis of delirium was determined by clinicians. Statistical analysis included Propensity Score Matching (PSM), χ2 Test, and Binary Logistic Regression. A total of 213 patients were included in this study, and the incidence of delirium was found to be 29.58 % (63/213). Among them, 126 patients were selected using PSM (delirium:non-delirium = 1:1), ensuring age, gender, and pathology were matched. According to the results of univariate analysis conducted on multiple variables, The binary logistic regression indicated that a history of alcoholism (OR = 6.89, [1.60–29.68], P = 0.010), preoperative optic nerve compression symptoms (OR = 4.30, [1.46–12.65], P = 0.008), operation time ≥3 h (OR = 5.50, [2.01–15.06], P = 0.001), benzodiazepines for sedation (OR = 3.94, [1.40–11.13], P = 0.010), sleep disorder (OR = 3.86, [1.40–10.66], P = 0.009), and physical restraint (OR = 4.53, [1.64–12.53], P = 0.004) as independent risk factors for postoperative delirium following pituitary adenoma surgery. For pituitary adenoma patients with a history of alcoholism and presenting symptoms of optic nerve compression, as well as an operation time ≥3 h, enhancing communication between healthcare providers and patients, improving perioperative sleep quality, and reducing physical restraint may help decrease the incidence of postoperative delirium. [ABSTRACT FROM AUTHOR]

The internal water and thermal state and performance of an air-cooled proton exchange membrane (PEM) fuel cell stack are strongly determined by the fan arrangement and operational characteristics. This study presents an innovative method to investigate the influence of fan on stack performance through integration of fan's full morphology, including the fan blade, grill between the fan and stack, etc. into a three-dimensional (3D) multiphase stack model. The multiple reference frame (MRF) model is implemented to simulate the air flow field caused by the rotation of fan and the multiple transfers coupled with electrochemical reactions is considered in the 3D stack model in detail. Through this integrated model, the influence of the air supply mode, fan number and duty ratio on stack performance and the distribution characteristics are investigated in detail. It is found that the air flowing into each cell in the fan-cooled stack is highly non-uniform, which increases the variations of oxygen concentration, temperature, and voltage in the stack. In comparison with the blowing mode, the suction mode helps to promote the uniformity of air supply with a lower air flow velocity. [ABSTRACT FROM AUTHOR]

• Extraventricular neurocytoma at the sellar region harbors benign clinical course. • The extent of resection may be the most important prognostic factor. • Hydrocephalus led by tumor progression may be the main cause of death in few cases. Extraventricular neurocytoma at the sellar region (EVNSR) is an exceedingly rare tumor. Given the paucity of specificity and its peculiar nature, our study aimed to characterize the clinical, imaging, and pathological features, including treatment and clinical outcomes of this tumor. Eight patients with pathologically confirmed EVNSR at Beijing Tiantan Hospital from 2012 to 2020 were retrospectively analyzed. Additionally, 7 cases from the prior detailed literature were also retrieved. Among the 8 patients from Beijing Tiantan Hospital, 2 males and 6 females with an average age of 45.3 (range, 8–61). Vision impairment and headache were the most common complaints at presentation. Preoperative diagnoses were pituitary adenoma (n = 6), meningioma (n = 1), and oligodendroglioma (n = 1). Treatment included subtotal tumor resection (n = 3), partial resection (n = 5), adjuvant therapy covered radiotherapy (n = 2), and gamma knife surgery (n = 3). The clinical outcomes of these 8 cases were stable (n = 5), survival after progression (n = 1), and death after recurrence (n = 2). EVNSRs are extremely rare tumors, and most have benign prognoses after appropriate treatment. Due to the unique location, total removal of the tumor is challenging; And adjuvant radiation therapy for eligible patients is recommended. Regular imaging review is also advised. Future studies with more patients are needed to elucidate the biological nature of EVNSRs. [ABSTRACT FROM AUTHOR]

• A novel airfoil flow field is proposed for fuel cells. • Airfoil flow field can enhance mass transfer while maintain low pressure drop. • Fuel cell with airfoil flow field is evaluated via experimental test and simulation. • Airfoil flow field increases the fuel cell's maximum power density effectively. • Airfoil flow field promotes the uniform distributions in fuel cells. Optimal configuration of bipolar plate (BP) embedding flow field is of great significance in improving the power density and durability of proton exchange membrane fuel cells (PEMFCs). Inspired by the airfoil in aircraft dividing the airflow into two streams causing pressure difference, a novel airfoil flow field (AFF) is designed to enhance the mass transfer capacity in channel and across the rib between two adjacent channels, which hardly increases the pressure drop in channel, unlike many baffle designs. The performance improvement achieved by implementing AFF in PEMFC is compared with common parallel flow field (PFF) and the wave flow field (WFF) by experimental test with respect to polarization curve and electrochemical loss and numerical simulation via a three-dimensional (3D) PEMFC model. The experimental results indicate that the novel AFF exhibits best fuel cell performance at various operation conditions (e.g. relative humidity, air stoichiometric ratio) mainly benefitted from the enhanced oxygen transfer, which contributes to the improvement of maximum power density by 8.85 % and 14.37 % compared to PFF and WFF, respectively. The modeling results indicate that the pressure drop increase in AFF is negligible compared with PFF, and is even slightly lower than WFF, indicating high practicability. Moreover, the utilization of AFF also helps the uniformity of oxygen concentration, current density and temperature in PEMFC. [ABSTRACT FROM AUTHOR]