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Recurrent epidemics of respiratory infections have drawn attention from the academic community and the general public in recent years. Aircraft plays a pivotal role in facilitating the cross-regional transmission of pathogens. In this study, we initially utilized an Airbus A320 model for computational fluid dynamics (CFD) simulations, subsequently validating the model's efficacy in characterizing cabin airflow patterns through comparison with empirical data. Building upon this validated framework, we investigate the transport dynamics of droplets of varying sizes under three air supply velocities. The Euler-Lagrangian method is employed to meticulously track key parameters associated with droplet transport, enabling a comprehensive analysis of particle behavior within the cabin environment. This study integrates acquired data into a novel PCR (Personal Contamination Rate) equation to assess individual contamination rates. Numerical simulations demonstrate that increasing air supply velocity leads to enhanced stability in the movement of larger particles compared to smaller ones. Results show that the number of potential infections in the cabin decreases by 51.8% at the highest air supply velocity compared to the base air supply velocity, and the total exposure risk rate reduced by 26.4%. Thus, optimizing air supply velocity within a specific range effectively reduces the potential infection area. In contrast to previous research, this study provides a more comprehensive analysis of droplet movement dynamics across various particle sizes. We introduce an improved method for calculating the breathing zone, thereby enhancing droplet counting accuracy. These findings have significant implications for improving non-pharmacological public health interventions and optimizing cabin ventilation system design. [ABSTRACT FROM AUTHOR]

Choledochal cysts (CCs) are an important risk factor for cholangiocarcinoma, though their etiology remains debated. Given the vital role of bile fluid in digestive processes within the biliary system, examining such mechanisms from the perspective of bile fluid dynamics may offer additional insights for clinical use. This study utilized magnetic resonance imaging (MRI)-based patient-specific scans for detailed reconstruction and further employed the computational fluid dynamic method to assess the physiological functions of each system, including refilling and emptying processes. The impact of bile rheological property was also examined. Key biomechanical parameters—pressure and wall shear stress (WSS)—were displayed on a two-dimensional plane via surface mapping for enhanced visualization and comparative analysis. Outcomes demonstrated a significant reduction in bile flow velocity in CCs patients due to common bile duct's anatomical features and bile's shear-thinning, non-Newtonian nature, with a notable increase in pressure drop observed. In healthy biliary systems, WSS variations were minimal; however, in CCs patients, extreme WSS differences were found, with the highest WSS in the segmental bile duct and the lowest in the dilatation area, presenting a magnitude difference of approximately 1000. CCs one showed WSS levels 100–250 times higher than healthy ones in the common bile duct. Bile rheological properties substantially affect pressure and WSS patterns, particularly WSS, where pathological bile caused a tenfold increase in WSS compared to healthy bile. The findings aimed to enhance the understanding of biliary fluid mechanics in CCs and offer insights into selected fluidic variables for future microfluidic chip experiments. [ABSTRACT FROM AUTHOR]

In vitro cell culturing witnessed its applications in scientific research and industrial activities. Attempts to shorten the doubling time of cultured cells have never ceased. In plants, auxin is applied to promote plant growth, the synthetic derivative 1‐Naphthaleneacetic acid (NAA) is a good example. Despite the auxin's naturally occurring receptors are not present in mammalian cells, studies suggested they may affect cell culturing. Yet the effects and mechanisms are still unclear. Here, an up to 2‐fold increase in the yield of in vitro cultured human cells is observed. Different types of human cell lines and primary cells are tested and found that NAA is effective in all the cells tested. The PI staining followed by FACS suggested that NAA do not affect the cell cycling. Apoptosis‐specific dye staining analysis implicated that NAA rescued cell death. Further bulk RNA sequencing is done and it is identified that the lipid metabolism‐engaging and anti‐apoptosis gene, ANGPTL4, is enhanced in expression upon NAA treatment. Studies on ANGPTL4 knockout cells indicated that ANGPTL4 is required for NAA‐mediated response. Thus, the data identified a beneficial role of NAA in human cell culturing and highlighted its potency in in vitro cell culturing. [ABSTRACT FROM AUTHOR]

Objective: To compare the strengths and limitations of the old and revised guidelines for the diagnosis in patients with idiopathic pulmonary fibrosis(IPF)., Methods: Patients who were admitted and diagnosed as interstitial lung diseases (ILDs) in our hospital from 2009 to 2014 were enrolled in our study.Eachpatient was reevaluated respectively according to the old and revised guidelines of IPF., Results: A total of 553 cases were initially reviewed, among whom 355 cases were excluded for pulmonary fibrosis secondary to definite underlying diseases, 28 excluded due to high resolution computed tomography(HRCT) not done, 26 excluded because serum immunology examination was not available.The remaining 144 cases were finally enrolled in this study including 92 males and 52 females with median age 21-92 (68 ± 11) years old. Twenty five patients (17.4%, 25/144) met the diagnostic criteria of IPF by the old guideline.While by the revised guideline, 53 patients (36.8%, 53/144) were diagnosed as classical IPF, 29 patients(20.1%, 29/144) as probable cases, another 69 non-IPF patients accounting for 43.1% (62/144). The result revealed that there's a significant difference between the two guidelines in the diagnosis of IPF., Conclusions: The revised guideline favors an early diagnosis of IPF and simplifies the diagnostic process.However the possibility of over diagnosis or missed diagnosis by the revised guideline does exist.On the other hand, despite of the delayed diagnosis by the old guideline, it may reduce the misdiagnosis of IPF in some circumstance.

Objective: Idiopathic pulmonary fibrosis (IPF) is defined as a specific form of chronic, progressive fibrosing interstitial pneumonia with unknown cause. We analyzed the changed rate of pulmonary function and arterial blood gas in IPF patients, and evaluated their influence of changed rate to IPF prognosis., Methods: 81 patients with IPF were recruited successfully, they were followed-up at 6 and 12 months. Dyspnea score and respiratory assessment parameters including FVC, FEV1, TLC, SaO2, PA-aO2, and DLCO were evaluated at their 6 and 12 months follow-up. The changed value and changed rate of above parameters were calculated, and their treatment effects were divided into 3 subgroup: improved, stable and deteriorated group. Statistical analysis was performed between groups for survival and hazards regression analysis., Results: 55 of 81 patients were follow-up at 12 months. Dyspnea score and its changed rate, the changed value of FEV1%, FVC%, TLC%, DLCO%, and PaO2, SaO2, PA-aO2 were prognosis effect factors in IPF patients in 6 and 12 months group. The survival analysis of dyspnea scores, FVC%, TLC%, DLCO%, PaO2, SaO2 and PA-aO2 at K-M were all statistical significant (P < 0.05) in improved, stable and deteriorated group., Conclusion: FVC% changed rate, dyspnea score changed rate and PaO2 changed rate were IPF patient prognosis associated factors in 6 months group; and FVC% changed rate, DLCO% changed rate and TLC% changed rate were prognosis associated factors for IPF patient in 12 months group.