1.A brief introduction of Xiangya's anti-epidemic history in a century.
Ping'an HU ; Yun WANG ; Lei PAN ; Shanqi HUANG
Journal of Central South University(Medical Sciences) 2020;45(5):481-488
Based on archival materials, the Xiangya's anti-epidemic history in a century from its establishment to 2020 is divided into 4 stages. The first stage (1906-1926), Edward Hicks Hume and YAN Fuqing, the founders of Xiangya, prevented and controlled smallpox and plague. The second stage (1929-1953), during the resumption of Xiangya, students prevented and controlled cholera, plague, dysentery, typhus, and other infectious diseases. In the third stage (1953-1999), in a peacetime, Xiangya actively fought against schistosomiasis, hydatidosis, malaria, leprosy, tuberculosis and other epidemics. The fourth stage (2000-2020), the era of Central South University. Medical staff in Xiangya fight SARS, influenza A (HN) flu, Ebola hemorrhagic fever, coronavirus disease 2019, etc. Over the past hundred years, Xiangya people joined together to spread benevolence and love, apply medical knowledge and skills, combat the epidemic and rescue people in difficulties, which made a great contribution to the motherland and the people.
Betacoronavirus
;
China
;
Communicable Disease Control
;
history
;
Communicable Diseases
;
history
;
Coronavirus Infections
;
Epidemics
;
history
;
History, 20th Century
;
History, 21st Century
;
Humans
;
Incidence
;
Pandemics
;
Pneumonia, Viral
2.Droplet freeze-thawing system based on solid surface vitrification and laser rewarming.
Wenxin ZHU ; Ping'an PAN ; Yonghua HUANG ; Wei CHEN ; Sha HAN ; Zheng LI ; Jinsheng CHENG
Journal of Biomedical Engineering 2023;40(5):973-981
Ultra-rapid cooling and rewarming rate is a critical technical approach to achieve ice-free cells during the freezing and melting process. A set of ultra-rapid solid surface freeze-thaw visualization system was developed based on a sapphire flim, and experiments on droplet freeze-thaw were carried out under different cryoprotectant components, volumes and laser energies. The results showed that the cooling rate of 1 μL mixed cryoprotectant [1.5 mol/L propylene glycol (PG) + 1.5 mol/L ethylene glycol (EG) + 0.5 mol/L trehalose (TRE)] could be 9.2×10 3 °C/min. The volume range of 1-8 μL droplets could be vitrified. After comparing the proportions of multiple cryoprotectants, the combination of equal proportion mixed permeability protectant and trehalose had the best vitrification freezing effect and more uniform crystallization characteristics. During the rewarming operation, the heating curve of glassy droplets containing gold nanoparticles was measured for the first time under the action of 400-1 200 W laser power, and the rewarming rate was up to the order of 10 6 °C/min. According to the droplet images of different power rewarming processes, the laser power range for ice-free rewarming with micron-level resolution was clarified to be 1 400-1 600 W. The work of this paper simultaneously realizes the ultra-high-speed temperature ramp-up, transient visual observation and temperature measurement of droplets, providing technical means for judging the ice free droplets during the freeze-thaw process. It is conducive to promoting the development of ultra-rapid freeze-thaw technology for biological cells and tissues.
Freezing
;
Vitrification
;
Cryopreservation/methods*
;
Trehalose
;
Gold
;
Rewarming
;
Metal Nanoparticles
;
Cryoprotective Agents
;
Lasers