The future of 3D food printing: Opportunities for space applications.

Over the past decade or so, there have been major advances in the development of 3D printing technology to create innovative food products, including for printing foods in homes, restaurants, schools, hospitals, and even space flight missions. 3D food printing has the potential to customize foods for individuals based on their personal preferences for specific visual, textural, mouthfeel, flavor, or nutritional attributes. Material extrusion is the most common process currently used to 3D print foods, which is based on forcing a fluid or semi-solid food "ink" through a nozzle and then solidifying it. This type of 3D printing application for space missions is particularly promising because a wide range of foods can be produced from a limited number of food inks in a confined area. This is especially important for extended space missions because astronauts desire and require a variety of foods, but space and resources are minimal. This review highlights the potential applications of 3D printing for creating custom-made foods in space and the challenges that need to be addressed.

A Second-Order Method for Removing Mixed Noise from Remote Sensing Images.

Remote sensing image denoising is of great significance for the subsequent use and research of images. Gaussian noise and salt-and-pepper noise are prevalent noises in images. Contemporary denoising algorithms often exhibit limitations when addressing such mixed noise scenarios, manifesting in suboptimal denoising outcomes and the potential blurring of image edges subsequent to the denoising process. To address the above problems, a second-order removal method for mixed noise in remote sensing images was proposed. In the first stage of the method, dilated convolution was introduced into the DnCNN (denoising convolutional neural network) network framework to increase the receptive field of the network, so that more feature information could be extracted from remote sensing images. Meanwhile, a DropoutLayer was introduced after the deep convolution layer to build the noise reduction model to prevent the network from overfitting and to simplify the training difficulty, and then the model was used to perform the preliminary noise reduction on the images. To further improve the image quality of the preliminary denoising results, effectively remove the salt-and-pepper noise in the mixed noise, and preserve more image edge details and texture features, the proposed method employed a second stage on the basis of adaptive median filtering. In this second stage, the median value in the original filter window median was replaced by the nearest neighbor pixel weighted median, so that the preliminary noise reduction result was subjected to secondary processing, and the final denoising result of the mixed noise of the remote sensing image was obtained. In order to verify the feasibility and effectiveness of the algorithm, the remote sensing image denoising experiments and denoised image edge detection experiments were carried out in this paper. When the experimental results are analyzed through subjective visual assessment, images denoised using the proposed method exhibit clearer and more natural details, and they effectively retain edge and texture features. In terms of objective evaluation, the performance of different denoising algorithms is compared using metrics such as mean square error (MSE), peak signal-to-noise ratio (PSNR), and mean structural similarity index (MSSIM). The experimental outcomes indicate that the proposed method for denoising mixed noise in remote sensing images outperforms traditional denoising techniques, achieving a clearer image restoration effect.

Advancements in 3D food printing: a comprehensive overview of properties and opportunities.

3D printing has numerous applications in the food industry that may enhance diversity, quality, healthiness, and sustainability. This innovative additive manufacturing technology has the ability to specifically tailor food properties for individuals. Nevertheless, several challenges still need to be overcome before 3D printing can be utilized more widely in the food industry. This article focuses on the development and characterization of "food inks" suitable for 3D printing of foods. Specifically, the main factors impacting successfully printed foods are highlighted, including material properties and printing parameters. The creation of a 3D printed food with the appropriate quality and functional attributes requires understanding and control of these factors. Food ink printability is an especially important factor that depends on their composition, structure, and physicochemical properties. Previous studies do not sufficiently describe the precise design and operation of 3D printers in sufficient detail, which makes comparing results challenging. Additionally, important physicochemical characteristics utilized in traditional food are not consistently reported in 3D inks, such as moisture content, water activity, and microbial contamination, which limits the practical application of the results. For this reason, we highlight important factors impacting 3D ink formulation and performance, then provide suggestions for standardizing and optimizing 3D printed foods.

Spinal Cord Protection of Aorto-Iliac Bypass in Open Repair of Extent II and III Thoracoabdominal Aortic Aneurysm.

BACKGROUND: Spinal cord injury (SCI) is one of the serious complications of thoracoabdominal aortic aneurysm (TAAA) repair. Cardiopulmonary bypass (CPB) and left heart bypass (LHB) are well-established extracorporeal circulatory assistance methods to increase distal aortic perfusion and prevent spinal cord ischaemia in TAAA repair. Aorto-iliac bypass, a new surgical adjunct offering distal aortic perfusion without the need of complex perfusion skills, was developed as a substitute for CPB and LHB. However, its spinal cord protective effect is unknown. METHODS: The perioperative data of 183 patients who had elective open Crawford extent II and III TAAA repair at our aortic centre from July 2011 to May 2019 were retrospectively analysed. Spinal cord protection was compared between the aorto-iliac bypass group (n=106) and the extracorporeal circulatory assistance group (n=77 [65 CPB, 12 LHB]), and the risk factors for SCI in these patients were explored. RESULTS: Eleven (11) patients had postoperative SCI: five (6.5%) in the extracorporeal circulatory assistance group (four with CPB and one with LHB), and six (5.7%) in the aorto-iliac bypass group. The incidence of SCI was 6.0% (11/183 cases). There was no difference between the aorto-iliac bypass group and the extracorporeal circulatory assistance group (p=1.0), while operation time, proximal aortic clamp time, intercostal artery clamp time, and length of intensive care unit stay were all increased in the latter group. Multivariate logistic regression analysis showed that cerebrospinal fluid pressure (odds ratio [OR] 1.270; 95% confidence interval [CI] 1.092-1.478 [p=0.002]) and lowest haemoglobin on the first postoperative day (OR 0.610; 95% CI 0.416-0.895 [p=0.011]) were the independent predictors of SCI in TAAA repair. CONCLUSIONS: Spinal cord protection of aorto-iliac bypass is comparable to that of CPB and LHB in open TAAA repair.

Anesthesia for Pregnant Women with Pulmonary Hypertension.

Despite advances in the therapy for pulmonary hypertension over the past decades, the prognosis of pregnant patients with pulmonary hypertension remains poor, with high maternal mortality. This poses a particular challenge for the mother and her medical team. In the present review, the authors have updated the classification and definition of pulmonary hypertension, summarized the current knowledge with regard to perioperative management and anesthesia considerations for these patients, and stressed the importance of a "pregnancy heart team" to improve long-term outcomes of pregnant women with pulmonary hypertension.

Effect of End-Tidal Carbon Dioxide on Cerebral Dynamics in Infants With Ventricular Septal Defect: A Comparison Between Sevoflurane and Intravenous Anesthetics.

OBJECTIVES: The primary aim was to compare the changes in regional cerebral oxygen saturation (rSO2) and cerebral blood flow velocity (CBFV) during sevoflurane and intravenous anesthesia when the end-tidal carbon dioxide partial pressure (PETCO2) changed in infants undergoing ventricular septal defect (VSD) repair. DESIGN: Prospective, observational study. SETTING: Tertiary care hospital. PARTICIPANTS: Patients younger than 6 months with VSDs. INTERVENTIONS: End-tidal carbon dioxide was increased by decreasing tidal volume or respiratory rate. MEASUREMENTS AND MAIN RESULTS: The infants were randomly assigned to receive either sevoflurane (SA group) or midazolam-sufentanil based intravenous anesthesia (IA group). PETCO2 levels of 30 mmHg (T1), 35 mmHg (T2), 40 mmHg (T3), or 45 mmHg (T4) were obtained by adjusting the tidal volume and respiratory rate. There were no significant intergroup differences in rSO2. In the SA group, as PETCO2 increased from T1 to T4, rSO2 increased significantly from 68.8% ± 5.9% to 76.4% ± 6.0% (p < 0.001). CBFV increased linearly, whereas the pulsatility index and resistance index decreased linearly from T1 to T4 (p < 0.001). In the IA group, rSO2 showed a significant increase from 68.6% ± 4.6% to 76.1% ± 6.2% with the change in PETCO2 from T1 to T4 (p < 0.001). CBFV increased linearly, whereas the pulsatility index and resistance index decreased linearly from T1 to T4 (p < 0.001). CONCLUSION: Cerebrovascular response to different PETCO2 levels was preserved and similar during clinically relevant doses of sevoflurane anesthesia and midazolam-sufentanil based intravenous anesthesia in infants younger than 6 months old undergoing VSD repair.

Chinese Society of Anesthesiology Expert Consensus on Anesthetic Management of Cardiac Surgical Patients With Suspected or Confirmed Coronavirus Disease 2019.

The outbreak of a new coronavirus (severe acute respiratory syndrome coronavirus 2 [SARS-CoV-2]) in China in December 2019 has brought serious challenges to disease prevention and public health. Patients with severe coronavirus disease 2019 (COVID-19) who undergo cardiovascular surgery necessitate extremely high demands from anesthesia personnel, and face high risks of mortality and morbidity. Based on the current understanding of COVID-19 and the clinical characteristics of cardiovascular surgical patients, the authors provide anesthesia management guidelines for cardiovascular surgery along with the prevention and control of COVID-19.

Effects of relative low minute ventilation on cerebral haemodynamics in infants undergoing ventricular septal defect repair.

BACKGROUND: Ventilation-associated changes in blood carbon dioxide levels are associated with various physiological changes in infants undergoing surgery. Studies on the effects of mechanical ventilation on cerebral haemodynamics especially for infants with CHD are scarce. AIM: This study was done to compare the changes in regional cerebral oxygen saturation and cerebral blood flow velocity when the end-tidal carbon dioxide partial pressure changed during different minute ventilation settings in infants undergoing ventricular septal defect repair. METHODS: A total of 67 patients less than 1 year old with ventricular septal defect were enrolled, and 65 patients (age: 6.7 ± 3.4 months, weight: 6.4 ± 1.5 kg) were studied. After anaesthesia induction and endotracheal intubation, the same mechanical ventilation mode (The fraction of inspired oxygen was 50%, and the inspiratory-to-expiratory ratio was 1:1.5.) was adopted. The end-tidal carbon dioxide partial pressure of 30 mmHg (T1), 35 mmHg (T2), 40 mmHg (T3), or 45 mmHg (T4) were obtained, respectively, by adjusting tidal volume and respiratory rate. Minute ventilation per kilogram was calculated by the formula: minute ventilation per kilogram = tidal volume * respiratory rate/kg. Regional cerebral oxygen saturation was monitored by real-time near-infrared spectroscopy. Cerebral blood flow velocity (systolic flow velocity, end-diastolic flow velocity, and mean flow velocity), pulsatility index, and resistance index were measured intermittently by transcranial Doppler. Systolic pressure, diastolic pressure, stroke volume index, and cardiac index were recorded using the pressure recording analytical method. RESULTS: As the end-tidal carbon dioxide partial pressure increased from 30 to 45 mmHg, regional cerebral oxygen saturation increased significantly from 69 ± 5% to 79 ± 4% (p < 0.001). Cerebral blood flow velocity (systolic flow velocity, end-diastolic flow velocity, and mean flow velocity) increased linearly, while pulsatility index and resistance index decreased linearly from T1 (systolic flow velocity, 84 ± 19 cm/second; end-diastolic flow velocity, 14 ± 4 cm/second; mean flow velocity, 36 ± 10 cm/second; pulsatility index, 2.13 ± 0.59; resistance index, 0.84 ± 0.12) to T4 (systolic flow velocity, 113 ± 22 cm/second; end-diastolic flow velocity, 31 ± 6 cm/second; mean flow velocity, 58 ± 11 cm/second; pulsatility index, 1.44 ± 0.34; resistance index, 0.72 ± 0.07) (p < 0.001). There were significant differences in changes of systolic flow velocity, end-diastolic flow velocity, mean flow velocity, pulsatility index, and resistance index as the end-tidal carbon dioxide partial pressure increased from 30 to 45 mmHg between subgroups of infants ≤6 and infants >6 months, while the changes of regional cerebral oxygen saturation between subgroups were not statistically different. Regional cerebral oxygen saturation and cerebral blood flow velocity (systolic flow velocity, end-diastolic flow velocity, and mean flow velocity) were negatively correlated with minute ventilation per kilogram (r = -0.538, r = -0.379, r = -0.504, r = -0.505, p < 0.001). Pulsatility index and resistance index were positively related to minute ventilation per kilogram (r = 0.464, r = 0.439, p < 0.001). The diastolic pressure was significantly reduced from T1 (41 ± 7 mmHg) to T4 (37 ± 6 mmHg) (p < 0.001). There were no significant differences in systolic pressure, stroke volume index, and cardiac index with the change of end-tidal carbon dioxide partial pressure from T1 to T4 (p = 0.063, p = 0.382, p = 0.165, p > 0.05). CONCLUSION: A relative low minute ventilation strategy increases regional cerebral oxygen saturation and cerebral blood flow, which may improve cerebral oxygenation and brain perfusion in infants undergoing ventricular septal defect repair.

Rapid Titration of Intravenous Treprostinil to Treat Severe Pulmonary Arterial Hypertension Postpartum: A Retrospective Observational Case Series Study.

BACKGROUND: Pulmonary hypertension during pregnancy carries high mortality rate. The relatively long-acting, specific pulmonary vasodilator treprostinil has been used to improve survival in these parturients. Slow uptitration is performed in most cases, and rapid titration has not been reported in the postpartum period. METHODS: We retrospectively reviewed 17 pregnant patients with severe pulmonary arterial hypertension who were treated with intravenous treprostinil in our institution between 2014 and 2016. Patients' demographic characteristics, etiology, functional status, mode of delivery, anesthetic administration, medical therapy, echocardiographic and hemodynamic measurements, subsequent clinical course, and maternal-fetal outcomes were assessed. The a priori primary outcome is maternal mortality in this study. RESULTS: Rapid titration of intravenous treprostinil was initiated at 1.25 ng/kg/min and increased to effective dose of 10 ng/kg/min by 1.25-2.5 ng/kg/min every 3 hours. In the next 24 hours, we adjusted the dosage to a median maximum dose of 15 ng/kg/min (interquartile range, 15-20 ng/kg/min) over a median uptitration period of 34 hours (interquartile range, 24-41 hours) for 17 parturients with severe pulmonary hypertension. Treprostinil was weaned off by 0.50-1.25 ng/kg/min every 3 hours in 94.3 ± 42.4 hours. Fifteen patients survived to discharge, and only 2 patients died of pulmonary hypertensive crisis (maternal mortality rate, 11.7%). No treprostinil infusion-related postpartum complication was observed. CONCLUSIONS: Our experience suggested that rapid uptitration of intravenous treprostinil combined with oral sildenafil in the postpartum period may be a safe and effective approach for these very sick parturients with severe pulmonary hypertension.

Intraoperative Transesophageal Echocardiography During Cardiovascular Surgery in China.

OBJECTIVE: To perform a comprehensive nationwide survey of more than 90% of all cardiovascular hospitals in China to assess the current 2018 status of transesophageal echocardiography (TEE) equipment, operating physicians, education, impact on surgery, and reimbursement. DESIGN: In this nationwide survey, 716 cardiovascular hospitals in mainland China were included. A 15-question electronic survey was sent to these hospitals and the data were received directly from the questionnaire website for analysis. SETTING: Cardiovascular hospitals in mainland China. PARTICIPANTS: Departments of anesthesiology in cardiovascular hospitals in mainland China. INTERVENTIONS: Answer a 15-question survey. MEASUREMENTS AND MAIN RESULTS: About 90% of hospitals have acquired machines to perform TEEs with most of the machines controlled by the ultrasound department. Anesthesiologists performed intraoperative TEEs in 45% of the hospitals, but only 15% of the hospitals have anesthesiologists who have met the basic TEE training requirements. Most anesthesiologists (68%) believed TEE significantly contributed to patient care during cardiovascular surgeries. The overwhelming majority of surveyed hospital staff (93%) stated that they were planning to continue or start intraoperative TEE examinations in the future. CONCLUSION: Many hospitals in China have acquired equipment to perform intraoperative TEE examinations during cardiovascular surgeries. However, the number of anesthesiologists who can perform TEEs independently still is not adequate. Standardized trainings, a formal certification process, and governmental payment model changes must be provided to ensure high-quality TEE services and better surgical outcomes in China.

Contraction of Surfactant-Laden Pores.

The contraction of surfactant-laden pores at the microscale has implications for natural and technological processes ranging from the collapse of channels in lipid membranes to the stability of foams in the food processing industry. Despite their prevalence, our understanding of the mechanisms of pore contraction in the presence of surfactants remains unclear. These mechanisms have been challenging to study experimentally given the small length scale near the singularity and simulations capable of accurately characterizing the pore dynamics may help enhance our understanding of the process. Here, we use high-fidelity numerical simulations to gain insight into the fluid dynamics and interfacial phenomena underlying the contraction of viscous pores in the presence of an insoluble surfactant. Results show that surfactants accumulate on the advancing front of a collapsing pore due to the uneven deformation of the pore interface. Because of this accumulation, even a small amount of surfactant plays a major role in the way in which a collapsing pore approaches the singularity.

Perioperative Management of Pregnant Women With Idiopathic Pulmonary Arterial Hypertension: An Observational Case Series Study From China.

OBJECTIVES: The mortality of pregnant women with idiopathic pulmonary arterial hypertension (PAH) is very high. There are limited data on the management of idiopathic PAH during pregnancy. The authors aimed to examine systematically the characteristics of parturient women with idiopathic PAH, to explore the adverse effects of idiopathic PAH on pregnancy outcomes, and to report the multidisciplinary perioperative management strategy from the largest comprehensive cardiac hospital in China. DESIGN: Observational case series study. SETTING: Tertiary referral acute care hospital in Beijing, China. PARTICIPANTS: The cases of 17 consecutive pregnant idiopathic PAH patients undergoing abortion or parturition at Anzhen Hospital were reviewed retrospectively. INTERVENTIONS: Preoperative characteristics, anesthesia method, intensive care management, PAH-specific therapy, and maternal and neonatal outcomes were analyzed in this case series study. MEASURES AND MAIN RESULTS: Maternal and neonatal outcomes were the main measures. The mean ages of the 17 parturient women with idiopathic PAH were 28.3 ± 5.4 years, and the mean systolic pulmonary arterial pressure was 97.9 ± 18.6 mmHg. Fifteen patients (88.2%) received PAH-specific therapy before delivery, including sildenafil, iloprost, and treprostinil. All except 1 parturient received epidural anesthesia for surgery due to an emergency Caesarean section. Three patients experienced pulmonary hypertension crisis that necessitated conversion to general anesthesia. Ten parturients underwent Caesarean delivery at a median gestational age of 31 weeks. Three patients developed acute pulmonary hypertensive crisis intraoperatively. Two patients underwent cardiopulmonary resuscitation and extracorporeal membrane oxygenation support. The maternal mortality was 17.6% (3/17). Of the 10 delivered neonates, 9 (90.0%) survived. CONCLUSIONS: The maternal mortality of the idiopathic PAH parturient was high in this case series from China. The authors applied epidural anesthesia, early management with multidisciplinary approaches, PAH-specific therapy, avoidance of oxytocin, and timely delivery or pregnancy termination to improve maternal and neonatal outcomes.

Current Status of Cardiovascular Anesthesia in China.

High quality and safe cardiac anesthesia is a prerequisite for success in cardiac care. Cardiac surgery has developed rapidly over recent years in China. Because of language barriers, the current status of cardiac anesthesia in China is not well known to Western countries. To assess practice patterns, volume, workforce, and training requirements of Chinese cardiovascular anesthesiologists, we surveyed 92 major cardiovascular centers in China regarding their anesthesia practice, monitoring techniques, resources, staffing, and work hours. We aim to provide a review of the history, new developments, and a current cross section of cardiac anesthesia practice patterns in China. The goal is to allow Western readers to understand the unique achievements and challenges in Chinese cardiovascular anesthesiology, thus promoting further communications with Chinese cardiovascular anesthesiologists.

Predictors of Prolonged Mechanical Ventilation in Adults After Acute Type-A Aortic Dissection Repair.

OBJECTIVES: Prolonged mechanical ventilation (PMV) after surgical repair of acute type-A aortic dissection (ATAAD) is associated with an increased risk for mortality and morbidity. The goal of this study was to evaluate the influence of PMV on early and late outcomes and to identify the risk factors for PMV after ATAAD repair. DESIGN, SETTING, AND PARTICIPANTS: This study was a retrospective analysis of prospectively collected data, which resulted from a prior clinical trial. Clinical outcomes were analyzed in 121 patients with ATAAD (mean age 46.6 ± 10.4; 93 men) who underwent total arch replacement combined with a frozen elephant trunk implantation at a mean of 3.6 days from onset. Multivariate analysis was used to identify risk factors for PMV after surgery. MEASUREMENTS AND MAIN RESULTS: The primary endpoint of this study was the occurrence of PMV after ATAAD surgery. The secondary end-points were risk factors for PMV, in-hospital mortality, and 1-year survival. Thirty-five (28.9%) patients required PMV. The PMV group demonstrated a longer ventilation time and length of intensive care unit stay (129 ± 79 h and 167 ± 119 h v 19 ± 10 h and 32 ± 23 h, respectively, p < 0.001). Postoperative mortality was 6.6% (8 of 121), including 6 (17.2%) in the PMV and 2 (2.3%) in the non-PMV groups (p = 0.003). PMV was associated with increased in-hospital mortality (odds ratio 6.4; 95% confidence interval 1.1-36.0; p = 0.036). Follow-up was complete in 88.6% (98 of 113) of patients at a mean of 26 months (1-39 mo). Survival at 1 year was significantly lower in the PMV group compared with the non-PMV group (77.1% v 95.3%, p = 0.002). Risk factors for PMV were the level of serum lactate (mmol/L) at the end of surgery (odds ratio 1.189; 95% confidence interval 1.026-1.377; p = 0.021) and a lower preoperative platelet count (109/L) (odds ratio 0.918; 95% confidence interval 0.847-0.994; p = 0.034). CONCLUSION: In this study, the occurrence of PMV was 28.9% in patients with ATAAD. A lower preoperative platelet count and a higher serum lactate level after ATAAD surgery were risk factors for PMV. Identification of risk factors may be helpful for preventing PMV and improving outcomes after surgical repair of ATAAD.

Novel Goal-Directed Hemodynamic Optimization Therapy Based on Major Vasopressor during Corrective Cardiac Surgery in Patients with Severe Pulmonary Arterial Hypertension: A Pilot Study.

INTRODUCTION: Pulmonary arterial hypertension (PAH) is a common and fatal complication of congenital heart disease (CHD). PAH-CHD increases the risk for postoperative complications. Recent evidence suggests that perioperative goal-directed hemodynamic optimization therapy (GDHOT) significantly improves outcomes in surgery patients. Standard GDHOT is based on major solution volume, vasodilators and inotropic therapy, while novel GDHOT is based on major vasopressor and inotropic therapy. Therefore, we tested whether standard or novel GDHOT improves surgical outcomes in PAH-CHD patients. METHODS: Forty PAH-CHD patients with a ventricular septal defect (VSD) and mean pulmonary arterial pressure (mPAP) >50 mmHg, who were scheduled for corrective surgery, were randomly assigned to 2 groups: SG (study group, n = 20) and CG (control group, n = 20). SG patients received perioperative hemodynamic therapy guided by novel GDHOT, while CG patients received standard GDHOT. Outcome data were recorded up to 28 days postoperatively. Ventilator time, length of ICU stay, and mortality were the primary endpoints. RESULTS: There were no significant differences in preoperative data, surgical procedure, and hospital mortality rates between the 2 groups. Time of mechanical ventilation and length of ICU stay were significantly shorter in SG patients compared to CG patients (P < .05, n = 20). Patients in SG showed a significantly increased systemic vascular resistance index and decreased cardiac index, but no change in pulmonary vascular resistance index at 12 and 24 hours after surgery compared to the controls (P < .05). Patients in SG had significantly decreased PAP, pulmonary arterial pressure/systemic arterial pressure (Pp/Ps), and RVSWI (right ventricular stroke work index) at 12 and 24 hours after surgery (P < .05, respectively). Patients in SG also showed significantly decreased central venous pressure at 4, 12, and 24 hours after surgery compared to those treated with standard protocol (P < .05). CONCLUSION: Our study provides clinical evidence that perioperative goal-directed hemodynamic optimization therapy based on major vasopressor is associated with reduced duration of postoperative respiratory support, and length of ICU stay in PAH-CHD patients undergoing elective surgery. These outcomes, then, may be linked to improved hemodynamics and preservation of right ventricular dynamic function.

Universal Scaling Law for the Collapse of Viscous Nanopores.

Below a threshold size, a small pore nucleated in a fluid sheet will contract to minimize the surface energy. Such behavior plays a key role in nature and technology, from nanopores in biological membranes to nanopores in sensors for rapid DNA and RNA sequencing. Here we show that nanopores nucleated in viscous fluid sheets collapse following a universal scaling law for the pore radius. High-fidelity numerical simulations reveal that the scaling is largely independent of the initial conditions, including the size, shape, and thickness of the original nanopore. Results further show that the scaling law yields a constant speed of collapse as observed in recent experiments. Nanopores in fluid sheets of moderate viscosity also attain this constant terminal speed provided that they are sufficiently close to the singularity.

[The application of peripartum use of pulmonary artery catheter in pregnant patients with pulmonary hypertension].

OBJECTIVE: To investigate the application and value of pulmonary artery catheterization (PAC) in pregnant patients with pulmonary hypertension (PH). METHODS: The clinical data of pregnant patients with PH who were treated between 2006 and 2014 in surgical intensive care unit (SICU) at Capital Medical University affiliated Beijing Anzhen Hospital were retrospectively analysed. The differences of the clinical characteristics and outcome between PAC inserted patients and PAC not inserted patients were compared. RESULTS: The systolic pulmonary artery pressure (sPAP) measured by preoperative echocardiography has no significant difference between the PAC inserted patients [(103.0 ± 24.1) mmHg (1 mmHg = 0.133 kPa)] and PAC not inserted patients [(96.4 ± 27.3) mmHg; P = 0.175]. SPAP may be overestimated or underestimated by echocardiography compared with PAC with a gap from -38.4 mmHg to 49.5 mmHg. The rates of idiopathic pulmonary arterial hypertension (20.0% vs 3.2%) and continuous use of epidural anesthesia (89.1% vs 65.1%) were higher in PAC inserted patients compared with PAC not inserted patients. Norepinephrine, dobutamine, sildenafil, alprostadil, iloprost and low molecular weight heparin were more widely used in PAC inserted patients. The mortality rate and the rates of low birth weight (63.9% vs 30.6%) and very low birth weight infants (19.4% vs 13.9%) were all higher in PAC inserted patients, while the rate of induced abortion was lower in this group (5.5% vs 17.5%). The length of stay in surgical intensive care unit [6.0 (5.0) d vs 1.0 (3.0) d], postoperative length of stay [8.0 (6.0) d vs 8.0 (4.0) d] and total hospital costs [43 999.22 (38 267.27) RMB vs 14 878.24 (10 564.47) RMB] were all higher in PAC inserted patients. The incidence rate of PAC related complications was 7.3%. CONCLUSIONS: In moderate or severe PH pregnant patients with severe clinical symptoms, perioperative insertion of PAC helps to monitor the perinatal pulmonary arterial pressure(PAP) and guide treatment, potentially improving clinical outcomes and lowering the short term mortality. PAC can't be replaced by echocardiography in measuring PAP.

Evaluating the Potential of Ozone Microbubbles for Inactivation of Tulane Virus, a Human Norovirus Surrogate.

This study investigated the efficacy of low-dose ozone microbubble solution and conventional aqueous ozone as inactivation agents against Tulane virus samples in water over a short period of time. Noroviruses are the primary cause of foodborne illnesses in the US, and the development of effective inactivation agents is crucial. Ozone has a high oxidizing ability and naturally decomposes to oxygen, but it has limitations due to its low dissolution rate, solubility, and stability. Ozone microbubbles have been promising in enhancing inactivation, but little research has been done on their efficacy against noroviruses. The study examined the influence of the dissolved ozone concentration, inactivation duration, and presence of organic matter during inactivation. The results showed that ozone microbubbles had a longer half-life (14 ± 0.81 min) than aqueous ozone (3 ± 0.35 min). After 2, 10, and 20 min postgeneration, the ozone concentration of microbubbles naturally decreased from 4 ppm to 3.2 ± 0.2, 2.26 ± 0.19, and 1.49 ± 0.23 ppm and resulted in 1.43 ± 0.44, 0.88 ± 0.5, and 0.68 ± 0.53 log10 viral reductions, respectively, while the ozone concentration of aqueous ozone decreased from 4 ppm to 2.52 ± 0.07, 0.43 ± 0.05, and 0.09 ± 0.01 ppm and produced 0.8 ± 0.28, 0.29 ± 0.41, and 0.16 ± 0.21 log10 reductions against Tulane virus, respectively (p = 0.0526), suggesting that structuring of ozone in the bubbles over the applied treatment conditions did not have a significant effect, though future study with continuous generation of ozone microbubbles is needed.

Mathematical Modeling of Alpha-Tocopherol Early Degradation Kinetics to Predict the Shelf-Life of Bulk Oils.

The kinetics of lipid oxidation includes a lag phase followed by an exponential increase in oxidation products, which cause rancidity. Current models focus on the slope of this exponential curve for shelf-life estimation, which still requires the measurement of full oxidation kinetics. In this paper, we analyzed the formation of lipid oxidation products in stripped soybean oil containing different levels of α-tocopherol. The lag phases of lipid hydroperoxides and headspace hexanal formation were found to have a strong positive correlation with the α-tocopherol depletion time. We propose that the kinetics of antioxidant (α-tocopherol) depletion occur during the lag phase and could serve as an early shelf-life indicator. Our results showed that α-tocopherol degradation can be described by Weibull kinetics over a wide range of initial concentrations. Furthermore, we conducted in silico investigations using Monte Carlo simulations to critically evaluate the feasibility and sensitivity of the shelf-life prediction using early antioxidant degradation kinetics. Our results revealed that the shelf life of soybean oil may be accurately predicted as early as 20% of the overall shelf life. This innovative approach provides a more efficient and faster assessment of shelf life, ultimately reducing waste and enhancing product quality.

A machine learning-guided modeling approach to the kinetics of α-tocopherol and myricetin synergism in bulk oil oxidation.

The shelf-life and quality of food products depend heavily on antioxidants, which protect lipids from free radical degradation. α-Tocopherol and myricetin, two potent antioxidants, synergistically enhance the prevention of oxidative rancidity in bulk oil systems. Understanding their degradation kinetics is essential for deepening our knowledge of their mechanisms and developing strategies to predict shelf-life before expiration. This paper introduces a generalized mathematical model to describe the degradation kinetics of α-tocopherol in the presence of myricetin. Using direct differential methods guided by a machine learning approach based on neural differential equations, we uncover two distinct phases of α-tocopherol degradation when coexisting with myricetin at varying concentration ratios. These findings inform the development of a mixed Weibull model that accurately captures the degradation process. Our study enhances the understanding of antioxidant interactions and provides a reliable method for predicting food system stability, offering valuable insights for optimizing natural antioxidants in food preservation.