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Background and Objectives Endoscopic sinus surgery is commonly performed for maxillary sinus (MS) disease, and the surgical extent of the MS medial wall or ostium varies. We examined the effect of MS surgery on nasal airflow and air-conditioning using computational fluid dynamics in five nasal cavity numerical models. Methods Four types of unilateral virtual MS surgery were conducted on the right MS based on computed tomography images of a 49-year-old man with normal anatomy. The five models were as follows: baseline (normal), middle meatal antrostomy (MMA), MMA with inferior meatal antrostomy (MMA+IMA), mega-antrostomy (MEGA), and endoscopic medial maxillectomy (EMM). Virtual simulator software and a stereoscopic display with haptic device were used for virtual surgery. Meshing software and computer fluid dynamics software were used to generate meshes and analyze airflow. Results The MMA and MMA+IMA results were similar to the baseline model. However, EMM and MEGA exhibited some physiological changes. The amount of airflow moving into the MS was largest in the EMM model, followed by the MEGA model. The distributions of wall shear stress and surface water-vapor increased near the enlarged MS ostium in EMM and MEGA. Skewed airflow partition and different airflow rates between the operated and unoperated sites of the nose also changed the air-conditioning characteristics. EMM substantially reduced the relative humidity in the nasopharynx, and MEGA showed a smaller reduction. Conclusion Among four surgery techniques, EMM produced the largest increase in wall shear stress and surface water vapor flux on the posterior surface of the MS and the greatest deterioration in the nasal cavity’s air-conditioning capacity. MEGA reduced the local airflow disturbance inside the MS and prevented excessive degeneration of the cavity’s overall air-conditioning capacity. In conclusion, MEGA and modified EMM approaches have physiological advantages over EMM, while securing a sufficient spatial extent of resection for surgery.

The sterilization operation in food production is a key process to ensure the safety of food products, and most existing technologies for food sterilization utilizes thermal and/or non-thermal effects. Conventional heat sterilization requires a heat transfer medium, which is completed in a certain period of time at a certain temperature. Electric field processing, a non-conventional food processing technology which utilizes both thermal and non-thermal effects, can reduce the effective temperature threshold and time of conventional heat sterilization, thereby better retaining the nutritional value of foods with less impact on the sensory quality, flavor and color. This paper reviews the principles of ohmic heating sterilization, high-voltage pulsed electric field sterilization and induced electric field sterilization as well as the frontiers and progress in these sterilization technologies in the food industry, discusses the characteristics and differences between the current electric field technologies, and presents an outlook on their future development.

[Objective] The effects of different mulching methods on the distribution of organic and inorganic carbon in soil aggregates on the Loess Plateau, and the mechanism under which soil aggregates sequester carbon under mulched conditions were determined in order to promote efficient management of dryland farm soil. [Methods] The study was conducted on a long-term positioning experiment beginning in 2012. Soil characteristics were studied from plots on which spring corn (“Xianyu 335”) was grown under three treatments: straw mulching (SM), film mulching (FM), and no mulching (CK). Carbon distribution and enzyme activities in aggregates of different particle sizes were determined by the wet sieve method. [Results] ① Organic carbon contents of aggregates of each particle size were significantly greater for SM than for CK (p2 mm in size, but significantly increased the reserves of aggregates 2 mm to 0.25 mm in size (p

The optimal control problems of degenerate parabolic equations have many applications in economics, physics, climatology, and so on. Motivated by the applications, we consider the optimal control problems of a class of nonlinear degenerate parabolic equations in this paper. The main result is that we deduce the first order necessary condition for the optimal control problem of nonlinear degenerate parabolic equations by variation method. Moreover, we investigate the uniqueness of the solutions to the optimal control problems. For the linear equations, we obtain the global uniqueness, while for the nonlinear equations, we obtain only the local uniqueness. Finally, we give a numerical example to validate the theoretical results.

Objective: This study aimed to explore a new method to improve the blueberry quality during the preservation. Methods: Blueberries were stored at 4 ℃ for 7 days in 0, 3, 6 and 10 mT static magnetic fields respectively. Meanwhile, the apparent morphology, weight loss rate, decay rate, content of anthocyanidin and total phenol cell membrane permeability, superoxide dismutase activity and content of malondialdehyde of blueberries were analyzed. Results: The physicochemical properties of blueberries improved significantly with the increase of magnetic-field strength. Compared with the control, most of the blueberries treated by 10 mT static magnetic field remained plump during the storage. The weight loss and decay rate of blueberries decreased by 55.63% and 62.14%, respectively. In addition, the loss of anthocyanin and phenolic substances was reduced. Conclusion: The quality of blueberry was significantly improved by static magnetic field-assisted preservation.

HighlightsOver half of male acute coronary syndrome patients were smokers in China.Smoking was associated with higher risk of critical cardiac symptoms at admission.Only 35.3% of smoking patients received smoking cessation interventions in China.BackgroundSmoking cessation is recognized as an effective and cost-effective strategy for improving the prognosis of patients with coronary heart disease. Despite this, few studies have evaluated the smoking prevalence and provision of smoking cessation interventions among patients with acute coronary syndrome (ACS) in China.ObjectivesTo evaluate the smoking prevalence, clinical conditions and in-hospital outcomes associated with smoking, and the provision of smoking cessation interventions among ACS patients in China.MethodsThis registry study was conducted using data from the Improving Care for Cardiovascular Disease in China project, a collaborative nationwide registry of the American Heart Association and the Chinese Society of Cardiology. Our study sample comprised 92,509 ACS inpatients admitted between November 2014 and December 2018. A web-based data collection platform was used to report required data.ResultsSmoking prevalence among male and female ACS patients was 52.4% and 8.0%, respectively. Patients younger than 45 years had the highest smoking rate (men: 68.0%; women: 14.9%). Compared with non-smokers, smokers had an earlier onset age of ACS and a greater proportion of severe clinical manifestations at admission, including ST-elevation myocardial infarction (67.8% versus 54.8%; p < 0.001) and substantially elevated myocardial injury markers (86.1% versus 83.0%; p < 0.001). After multivariable adjustment, smoking was associated with higher risk of critical cardiac symptoms at admission (OR = 1.14, 95% CI: 1.08-1.20; p < 0.001) and had no direct association with in-hospital outcomes (OR = 0.93, 95% CI: 0.84-1.02; p = 0.107) of ACS patients. Of 37,336 smokers with ACS, only 35.3% received smoking cessation interventions before discharge. There was wide variation in provision of smoking cessation interventions across hospitals (0%-100%).ConclusionsSmoking is highly prevalent among ACS patients in China. However, smoking cessation interventions are not widely adopted in clinical practice in China as part of formal treatment strategies for ACS patients, indicating an important target for quality improvement.Clinical trial registrationURL: http://www.clinicaltrials.gov. Unique identifier: NCT02306616.

Objective: In order to improve freshness preservation quality of the fresh-cut shiitake mushroom. Methods: Carbon quantum dots were synthesized from dragon fruit peel and ethylenediamine, and characterized for stability and toxicity. Fresh-cut shiitake mushrooms were studied, and stored at 4 ℃ for 10 d after coating with 0.0, 1.5, 3.0 and 4.5 mL/100 mL carbon quantum dots-chitosan （N-CDs/CH） for preservation treatment. During the period of preservation, the weight loss, color difference, soluble solids and polyphenol oxidase were measured every 24 h to evaluate the preservation effect of the composite films. Results: The synthesized N-CDs had the typical characteristics, which had good fluorescence stability, hydroxyl and amino groups on outer surface, and no cytotoxicity. After fresh-cut shiitake mushrooms were treated with different concentrations of N-CDs/CH until the 10th day of storage, 4.5 mL/100 mL N-CDs/CH coating group had weight loss of 3.31%, coloration of 10.32, soluble solids of 4%, and polyphenol oxidase （PPO） activity of 104.65 U/(kg·s), all of which were significantly better than the blank group and other treatment groups （P＜0.05）. Conclusion: The preservation effect at the 4.5 mL/100 mL of N-CDs/CH coating was significantly better than that of blank and others （P＜0.05）. N-CDs/CH coating inhibited water loss and PPO activity, improved color and enhanced the preservation quality of fresh-cut shiitake mushroom.