Modelling the roles of visitor flows and returning migrants in the spatial diffusion of COVID-19 from Wuhan city in China.

COVID-19 has spread to many cities and countries in the world since the major outbreak in Wuhan city in later 2019. Population flow is the main channel of COVID-19 transmission between different cities and countries. This study recognizes that the flows of different population groups such as visitors and migrants returning to hometown are different in nature due to different length of stay and exposure to infection risks, contributing to the spatial diffusion of COVID-19 differently. To model population flows and the spatial diffusion of COVID-19 more accurately, a population group based SEIR (susceptible-exposed-infectious-recovered) metapopulation model is developed consisting of 32 regions including Wuhan, the rest of Hubei and other 30 provinces in Mainland China. The paper found that, in terms of the total export, Wuhan residents as visitors and Wuhan migrants returned to hometown were the first and second largest contributors in the simulation period. In terms of the net export, Wuhan migrants returned to hometown were the largest contributor, followed by Wuhan residents as visitors.

Measuring the impact of mitigation measures on infection risk of covid-19 in Hong Kong since February 2020.

Is it possible to control the covid-19 pandemic in large cities like Hong Kong? Many cities have adopted various mitigation measures to contain the covid-19 pandemic. But few studies have been made to measure the impact of mitigation measures on infection risk at city level such as Hong Kong. This paper introduced three indicators to measure the infection risk of covid-19 under mitigation measures: the infection rate, the primary risk of infection and daily risk of infection. Two factors are introduced to consider the impact of mitigation measures on infection risk in Hong Kong. They are the number of trips per day and the percentage of people wearing face masks. With these two mitigation measures, the daily risk of infection was reduced from 1826.11 per million to 644.58 per million in the peak of covid-19 infection on 2 August 2020. The covid-19 infection risk would be 2.83 times higher if above mitigation measures were not adopted. The covid-19 pandemic continues in 2021 and city governments are strongly recommended to take effective measures to encourage the public to reduce unnecessary trips and wear face mask before the pandemic is fully controlled.

Concurrent ROS1 gene rearrangement and KRAS mutation in lung adenocarcinoma: A case report and literature review.

Lung adenocarcinomas with gene rearrangement in the receptor tyrosine kinase ROS1 have emerged as a rare molecular subtype. Although these lung adenocarcinomas respond to ROS1tyrosine kinase inhibitors, many patients ultimately acquire resistance. ROS1gene rearrangement is generally mutually exclusive with other driver genomic alterations, such as those in EGFR, KRAS, or ALK, thus multiple genomic alterations are extremely rare. Herein, we report a case of a 42-year-old man diagnosed with lung adenocarcinoma positive for a SDC4-ROS1 fusion, who was treated with crizotinib followed by three cycles of chemotherapy. A biopsy acquired after disease progression revealed the original SDC4-ROS1 fusion along with a KRAS point mutation (p.G12D).We reviewed the related literature to determine the frequency of gene mutations in non-small cell lung cancer patients. A better understanding of the molecular biology of non-small cell lung cancer with multiple driver genomic aberrations will assist in determining optimal treatment.

The making of new regionalism in the cross-boundary metropolis of Hong Kong-Shenzhen, China.

In the age of globalization, new regionalism has become a new trend of regional development. This study examines the making of new regionalism in South China, using the case of Hong Kong-Shenzhen region. By tracing the process of Hong Kong and Shenzhen integration during the past three decades, the research finds three stages in Hong Kong-Shenzhen regionalization after the late 1970s, namely, the emergence of informal regional society from below, the transitional regional society and formal regional society, with reference to Hettne's concept of regionness. Hong Kong's internal economic, political and societal difficulties and external changing conditions are conducive to Hong Kong government's re-regulation toward a more positive stance on cross-boundary regionalization. Although intense economic and social interactions exist between Hong Kong and Shenzhen, a cross-boundary regional community has not emerged yet. The slow development of cross-boundary regional community is different from European case. The active participation of the governments aims to facilitate cross-boundary economic and infrastructure development and planning. This can take place well before reaching higher level of regionness: the formation of a regional community or the regional institutionalized polity.