In order to solve the problems of difficult test, high cost and long cycle in the development of large-scale airborne negative pressure isolation system, the simulation analysis of negative pressure response characteristics is carried out around various aviation conditions such as aircraft ascending, leveling and descending, especially rapid decompression, based on the computational fluid dynamics (CFD) method. The results showed that the isolation cabin could achieve -50 Pa pressure difference environment and form a certain pressure gradient. The exhaust air volume reached the maximum value in the early stage of the aircraft's ascent, and gradually decreased with the increase of altitude until it was level flying. In the process of aircraft descent, the exhaust fan could theoretically maintain a pressure difference far below -50 Pa without working; Under the special condition of rapid pressure loss, it was difficult to deal with the rapid change of low pressure only by the exhaust fan, so it was necessary to design safety valve and other anti-leakage measures in the isolation cabin structure. Therefore, the initial stage of aircraft ascent is the key stage for the adjustment and control of the negative pressure isolation system. By controlling the exhaust air volume and adjusting parameters, it can adapt to the change of low pressure under normal flight conditions, form a relatively stable negative pressure environment, and meet the needs of biological control, isolation and transport.
Aircraft ; Computer Simulation ; Aviation/instrumentation* ; Humans ; Hydrodynamics ; Air Pressure ; Equipment Design ; Pressure

In order to detect the environmental data of isolated cabin under various environmental conditions,a negative pressure cabin environment detector for aviation was developed,which was composed of a shell,a differential pressure transmitter,a pressure sensor,a carbon dioxide concentration sensor,an oxygen concentration sensor,a temperature and humidity sensor,a data processing module,a liquid crystal display(LCD)screen and USB data interface.It could environmental data such as carbon dioxide concentration,oxygen concentration,temperature,humidity,pressure difference between cabin and outside the cabin and air pressure outside the cabin in real time,the data processing module collected and processed the data,the data and data change curves was displayed in real time by the LCD screen,and the detection data was extracted through the USB data interface.When used in aviation environment,the detector could work continuously without fault for no less than 300 hours,and the average fault repair time was about 30 minutes,with good performance and high detection accuracy,which can provide convenience for the environmental data detection of negative pressure cabins,and is worthy of popularization.

The corona virus disease 2019 (COVID-19) caused by the new coronavirus (SARS-CoV-2) has spread rapidly around the world,posing a serious threat to the public"s health. As of September 30,2020,the number of infected people in the world has reached 33 million,causing more than 1 million deaths. Normalized nucleic acid detection methods based on lab have long turnaround time and high cost. Therefore,there is an urgent need to develop a convenient method to detect SARS-CoV-2,so as to achieve rapid testing and timely control of the epidemic when resources are limited.This review summarizes the point-of-care testing (POCT) methods developed for SARS-CoV-2 in terms of extraction,amplification and detection,and briefly introduces commercial POCT instruments that integrate these three steps,in order to provide references for emergency response and rapid deployment of COVID-19 and other emerging infectious diseases.

Objective:To investigate any effect of different environments on the levels of adrenocorticotropic hormone (ACTH), cortisol and testosterone using SAMP8 senescence-accelerated mice.Methods:Thirty SAMP8 mice were randomly divided into an enriched environment (EE) group, an impoverished environment (IE) group and a standard environment (SE) group, each of 10. The serum levels of ACTH, cortisol and testosterone were measured in all of the mice after they had lived in their respective environments for 8 weeks.Results:The average ACTH concentrations of the IE, EE and SE groups were (60.54±16.22), (48.98±15.30) and (28.49±8.24)pg/ml respectively. The average cortisol concentrations were (5.37±0.81), (4.09±0.92) and (3.19±0.88)ng/ml. The average testosterone concentrations being (2.35±0.90), (7.07±1.57) and (3.16±1.10)ng/ml. The average ACTH and cortisol levels were significantly different between the SE and IE groups. The average ACTH and testosterone levels differed significantly between the SE and EE groups and between the EE and IE groups.Conclusions:An impoverished environment can increase the secretion of ACTH and cortisol and activate the hypothalamic-pituitary-adrenal axis, at least in SAMP8 mice. An enriched environment can promote the secretion of ACTH and testosterone, but not that of cortisol.

Objective:To explore the characteristics of cognitive function in patients with early onset and adult onset schizophrenia.Methods:In this cross-sectional study, 546 patients with schizophrenia who met the Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition (DSM-Ⅳ) were selected.Among them, 62 cases were defined as early onset schizophrenia (EOS, age of onset＜18 years) and 175 patients were defined as adult onset schizophrenia (AOS, age of onset≥25 years).Patients underwent clinical assessments with the Positive and Negative Symptom Scale (PANSS) and the Personal and Social Performance Scale (PSP), and comprehensive neuropsychological assessments.Results:The EOS patients got lower scores in motor function-PEGDOM T score [ (26±12) vs. (30±11), P＜0.01], working memory-average T score of PASAT and WMSSP[ (34±12) vs. (38±10), P＜0.05]and executive function (inhibition) -Stroop T score [ (35±12) vs. (39±10), P＜0.05]than AOS patients.No differences were fund in processing speed, verbal memory and learning, visual memory and learning (Ps＞0.05) between the two groups.Conclusion:It suggests that the EOS patients have worse motor function, working memory and inhibition.