Effects of a closed-loop system against SARS-CoV-2 at the Beijing 2022 Olympic Winter Games: a descriptive and modeling study.

Background: To assess the efficacy of the epidemic prevention measures of the "closed-loop" system adopted by the Beijing 2022 Olympic Winter Games (BOWG).

Methods: We retrospectively collected and analyzed information, including age, sex, nationality, vaccination status, date of diagnosis, and date of entry, from 280 SARS-CoV-2-positive individuals identified during the BOWG. A susceptibility-exposed-infectious-remove model was employed to evaluate the effectiveness of epidemic prevention strategies on controlling the spread of SARS-CoV-2 under different scenarios during the BOWG.

A Chess and Card Room-Induced COVID-19 Outbreak and Its Agent-Based Simulation in Yangzhou, China.

Objective: To evaluate epidemiological characteristics of the COVID-19 outbreak that resurged in Yangzhou and to simulate the impact of different control measures at different regional scales.

Methods: We collected personal information from 570 laboratory-confirmed cases in Yangzhou from 28 July to 26 August 2021, and built a modified susceptible-exposed-infected-removed (SEIR) model and an agent-based model.

Results: The SEIR model showed that for passengers from medium-high risk areas, pre-travel nucleic acid testing within 3 days could limit the total number of infected people in Yangzhou to 50; among elderly persons, a 60% increase in vaccination rates could reduce the estimated infections by 253.

The Analysis of Patterns of Two COVID-19 Outbreak Clusters in China.

Since the emergence of COVID-19, there have been many local outbreaks with foci at shopping malls in China. We compared and analyzed the epidemiological and spatiotemporal characteristics of local COVID-19 outbreaks in two commercial locations, a department store building (DSB) in Baodi District, Tianjin, and the Xinfadi wholesale market (XFD) in Fengtai District, Beijing. The spread of the infection at different times was analyzed by the standard deviation elliptical method.

Clinical application and improvement of a CNN-based autosegmentation model for clinical target volumes in cervical cancer radiotherapy.

Objective: Clinical target volume (CTV) autosegmentation for cervical cancer is desirable for radiation therapy. Data heterogeneity and interobserver variability (IOV) limit the clinical adaptability of such methods. The adaptive method is proposed to improve the adaptability of CNN-based autosegmentation of CTV contours in cervical cancer.

An evaluation of COVID-19 transmission control in Wenzhou using a modified SEIR model.

In December 2019, the first confirmed case of pneumonia caused by a novel coronavirus was reported. Coronavirus disease 2019 (COVID-19) is currently spreading around the world. The relationships among the pandemic and its associated travel restrictions, social distancing measures, contact tracing, mask-wearing habits and medical consultation efficiency have not yet been extensively assessed.

Estimating hourly PM concentrations in Beijing with satellite aerosol optical depth and a random forest approach.

Assessing short-term exposure to PM requires the concentration distribution at a high spatiotemporal resolution. Abundant researches have derived the daily predictions of fine particles, but estimating hourly PM is still a challenge restrained by the input data. The recent aerosol optical depth (AOD) product from Himawari-8 provides hourly satellite observations informative to modelling.

A method of using deep learning to predict three-dimensional dose distributions for intensity-modulated radiotherapy of rectal cancer.

Purpose: To develop and test a three-dimensional (3D) deep learning model for predicting 3D voxel-wise dose distributions for intensity-modulated radiotherapy (IMRT).

Methods: A total of 122 postoperative rectal cancer cases treated by IMRT were considered in the study, of which 100 cases were randomly selected as the training-validating set and the remaining as the testing set. A 3D deep learning model named 3D U-Res-Net_B was constructed to predict 3D dose distributions.

Deceleration of Liver Regeneration by Knockdown of Heme Oxygenase-1 is Associated With Impairment of Liver Injury Recovery After Reduced-Size Liver Transplantation in Rats.

Aim: It has been reported that heme oxygenase-1 (HO-1) is upregulated during hepatocyte proliferation. Herein, we used a half-size liver transplantation (HSLT) model to study the impact of HO-1 on liver grafts proliferation. To the best of our knowledge, this is the first time that HO-1 has been characterized as a regulator of liver graft regeneration.

Landscape of emerging and re-emerging infectious diseases in China: impact of ecology, climate, and behavior.

For the past several decades, the infectious disease profile in China has been shifting with rapid developments in social and economic aspects, environment, quality of food, water, housing, and public health infrastructure. Notably, 5 notifiable infectious diseases have been almost eradicated, and the incidence of 18 additional notifiable infectious diseases has been significantly reduced. Unexpectedly, the incidence of over 10 notifiable infectious diseases, including HIV, brucellosis, syphilis, and dengue fever, has been increasing.

Detection of Multiple Parallel Transmission Outbreak of Streptococcus suis Human Infection by Use of Genome Epidemiology, China, 2005.

Streptococcus suis sequence type 7 emerged and caused 2 of the largest human infection outbreaks in China in 1998 and 2005. To determine the major risk factors and source of the infections, we analyzed whole genomes of 95 outbreak-associated isolates, identified 160 single nucleotide polymorphisms, and classified them into 6 clades. Molecular clock analysis revealed that clade 1 (responsible for the 1998 outbreak) emerged in October 1997.

A spatial, social and environmental study of tuberculosis in China using statistical and GIS technology.

Tuberculosis (TB) remains a major public health problem in China, and its incidence shows certain regional disparities. Systematic investigations of the social and environmental factors influencing TB are necessary for the prevention and control of the disease. Data on cases were obtained from the Chinese Center for Disease and Prevention.

Spatial interpolation of fine particulate matter concentrations using the shortest wind-field path distance.

Effective assessments of air-pollution exposure depend on the ability to accurately predict pollutant concentrations at unmonitored locations, which can be achieved through spatial interpolation. However, most interpolation approaches currently in use are based on the Euclidean distance, which cannot account for the complex nonlinear features displayed by air-pollution distributions in the wind-field. In this study, an interpolation method based on the shortest path distance is developed to characterize the impact of complex urban wind-field on the distribution of the particulate matter concentration.

Spatial-temporal characteristics of epidemic spread in-out flow-Using SARS epidemic in Beijing as a case study.

For better detecting the spatial-temporal change mode of individual susceptible-infected-symptomatic-treated-recovered epidemic progress and the characteristics of information/material flow in the epidemic spread network between regions, the epidemic spread mechanism of virus input and output was explored based on individuals and spatial regions. Three typical spatial information parameters including working unit/address, onset location and reporting unit were selected and SARS epidemic spread in-out flow in Beijing was defined based on the SARS epidemiological investigation data in China from 2002 to 2003 while its epidemiological characteristics were discussed. Furthermore, by the methods of spatial-temporal statistical analysis and network characteristic analysis, spatial-temporal high-risk hotspots and network structure characteristics of Beijing outer in-out flow were explored, and spatial autocorrelation/heterogeneity, spatial-temporal evolutive rules and structure characteristics of the spread network of Beijing inner in-out flow were comprehensively analyzed.

Exploring the epidemic transmission network of SARS in-out flow in mainland China.

The changing spatiotemporal patterns of the individual susceptible-infected-symptomatic-treated-recovered epidemic process and the interactions of information/material flows between regions, along with the 2002-2003 Severe Acute Respiratory Syndrome (SARS) epidemiological investigation data in mainland China, including three typical locations of individuals (working unit/home address, onset location and reporting unit), are used to define the in-out flow of the SARS epidemic spread. Moreover, the input/output transmission networks of the SARS epidemic are built according to the definition of in-out flow. The spatiotemporal distribution of the SARS in-out flow, spatial distribution and temporal change of node characteristic parameters, and the structural characteristics of the SARS transmission networks are comprehensively and systematically explored.

Aspirin-triggered lipoxin A4 attenuates LPS-induced pro-inflammatory responses by inhibiting activation of NF-κB and MAPKs in BV-2 microglial cells.

Background: Microglial activation plays an important role in neurodegenerative diseases through production of nitric oxide (NO) and several pro-inflammatory cytokines. Lipoxins (LXs) and aspirin-triggered LXs (ATLs) are considered to act as 'braking signals' in inflammation. In the present study, we investigated the effect of aspirin-triggered LXA4 (ATL) on infiammatory responses induced by lipopolysaccharide (LPS) in murine microglial BV-2 cells.

CD81 inhibits the proliferation of astrocytes by inducing G(0)/G (1) arrest in vitro.

Astrocytes play a major role in the reactive processes in response to neuronal injuries in the brain. Excessive gliosis is detrimental and can contribute to neuronal damage. CD81 (TAPA), a member of the tetraspanin family of proteins, is upregulated by astrocytes after traumatic injury to the rat central nervous system (CNS).

Transmission of SARS in three Chinese hospitals.

Objective: To quantify the transmissibility of severe acute respiratory syndrome (SARS) in hospitals in mainland China and to assess the effectiveness of control measures.

Methods: We report key epidemiological details of three major hospital outbreaks of SARS in mainland China, and estimate the evolution of the effective reproduction number in each of the three hospitals during the course of the outbreaks.

Results: The three successive hospital outbreaks infected 41, 99 and 91 people of whom 37%, 60% and 70% were hospital staff.

Geographical spread of SARS in mainland China.

Objectives: To describe the spatiotemporal diffusion of the severe acute respiratory syndrome (SARS) epidemic in mainland China, and to analyse the spatial pattern of SARS transmission from the Beijing epicentre to its neighbouring areas.

Methods: Probable SARS cases occurring between November 2002 and May 2003 in mainland China were compiled from different sources and geo-coded into a geographical information database based on onset location. Spatial analyses including kernel density estimation, and spatial statistical and tracking analyses were performed to characterise the spatiotemporal distribution of SARS cases based on onset location/date.

Effect of ciliary neurotrophic factor on activation of astrocytes in vitro.

Objective To observe the activating effect of ciliary neurotrophic factor (CNTF) on astrocyte in vitro. Methods Astrocytes cultured purely from newborn rats. Cerebral cortex was raised in normal and serum deprivation condition with different concentrations (in ng/ml: 0, 2, 20, or 200) of CNTF.