Omicron variant susceptibility to neutralizing antibodies induced in children by natural SARS-CoV-2 infection or COVID-19 vaccine

The novel SARS-CoV-2 Omicron variant may increase the risk of re-infection and vaccine breakthrough infections as it possesses key mutations in the spike protein that affect neutralizing antibody response. Most studies on neutralization susceptibility were conducted using specimens from adult COVID-19 patients or vaccine recipients. However, since the paediatric population has an antibody response to SARS-CoV-2 infection that is distinct from the adult population, it is critical to assess the neutralization susceptibility of pediatric serum specimens. This study compared the neutralization susceptibility of serum specimens collected from 49 individuals of <18 years old, including 34 adolescent BNT162b2 (Pfizer-BioNTech) vaccine recipients, and 15 recovered COVID-19 patients aged between 2 and 17. We demonstrated that only 38.2% of BNT162b2 vaccine recipients and 26.7% of recovered COVID-19 patients had their serum neutralization titre at or above the detection threshold in our live virus microneutralization assay. Furthermore, the neutralizing antibody titer against the Omicron variant was substantially lower than those against the ancestral virus or the Beta variant. Our results suggest that vaccine recipients and COVID-19 patients in the pediatric age group will likely be more susceptible to vaccine breakthrough infections or reinfections due to the Omicron variant than previous variants

Epidemiology of Acute Myocarditis/Pericarditis in Hong Kong Adolescents Following Comirnaty Vaccination

BACKGROUND: Age-specific incidence of acute myocarditis/pericarditis in adolescents following Comirnaty vaccination in Asia is lacking. This study aimed to study the clinical characteristics and incidence of acute myocarditis/pericarditis among Hong Kong adolescents following Comirnaty vaccination. METHODS: This is a population cohort study in Hong Kong that monitored adverse events following immunization through a pharmacovigilance system for COVID-19 vaccines. All adolescents aged between 12 and 17 years following Comirnaty vaccination were monitored under the COVID-19 vaccine Adverse Event Response and Evaluation Programme. The clinical characteristics and overall incidence of acute myocarditis/pericarditis in adolescents following Comirnaty vaccination were analysed. RESULTS: Between 14 June 2021 and 4 September 2021, 33 Chinese adolescents who developed acute myocarditis/pericarditis following Comirnaty vaccination were identified. 29 (87.88%) were males and 4 (12.12%) were females, with a median age of 15.25 years. 27 (81.82%) and 6 (18.18%) cases developed acute myocarditis/pericarditis after receiving the second and first dose, respectively. All cases are mild and required only conservative management.The overall incidence of acute myocarditis/pericarditis was 18.52 (95% Confidence Interval [CI], 11.67-29.01) per 100,000 persons vaccinated. The incidence after the first and second doses were 3.37 (95%CI 1.12-9.51) and 21.22 (95%CI 13.78-32.28 per 100,000 persons vaccinated, respectively. Among male adolescents, the incidence after the first and second doses were 5.57 (95% CI 2.38-12.53) and 37.32 (95% CI 26.98-51.25) per 100,000 persons vaccinated. CONCLUSIONS: There is a significant increase in the risk of acute myocarditis/pericarditis following Comirnaty vaccination among Chinese male adolescents, especially after the second dose

Studies in RF power communication, SAR, and temperature elevation in wireless implantable neural interfaces

Implantable neural interfaces are designed to provide a high spatial and temporal precision control signal implementing high degree of freedom real-time prosthetic systems. The development of a Radio Frequency (RF) wireless neural interface has the potential to expand the number of applications as well as extend the robustness and longevity compared to wired neural interfaces. However, it is well known that RF signal is absorbed by the body and can result in tissue heating. In this work, numerical studies with analytical validations are performed to provide an assessment of power, heating and specific absorption rate (SAR) associated with the wireless RF transmitting within the human head. The receiving antenna on the neural interface is designed with different geometries and modeled at a range of implanted depths within the brain in order to estimate the maximum receiving power without violating SAR and tissue temperature elevation safety regulations. Based on the size of the designed antenna, sets of frequencies between 1 GHz to 4 GHz have been investigated. As expected the simulations demonstrate that longer receiving antennas (dipole) and lower working frequencies result in greater power availability prior to violating SAR regulations. For a 15 mm dipole antenna operating at 1.24 GHz on the surface of the brain, 730 uW of power could be harvested at the Federal Communications Commission (FCC) SAR violation limit. At approximately 5 cm inside the head, this same antenna would receive 190 uW of power prior to violating SAR regulations. Finally, the 3-D bio-heat simulation results show that for all evaluated antennas and frequency combinations we reach FCC SAR limits well before 1 °C. It is clear that powering neural interfaces via RF is possible, but ultra-low power circuit designs combined with advanced simulation will be required to develop a functional antenna that meets all system requirements. © 2013 Zhao et al

The relevance of transport-development strategies to understanding travel behaviour and transport sustainability in Hong Kong

This study examines local residents' travel behaviour in three Hong Kong new towns against transport-development strategies. Transport sustainability under the transport-led, development-led and integrated transport and development strategies, are examined by various travel indicators under the broad categories of spatial distribution and modal split. The results suggest that differences in transport sustainability can be explained by the built environment, land use and transport characteristics associated with the three strategies. Hence, it is important to consider the impact of transport-development strategies on urban development and fully integrate them into sustainable transport planning

Higher Education Activities in World Cities: A Spatial Study of Global Leadership and Connectivity

Key characteristic of globalization is intensified interconnectedness among different places and individuals, beyond exchanges led by states and governments. However, existing literature on the geographies of higher education under globalization primarily focuses on the interactions at the regional scale and the intercountry level. Little is known about the disaggregate distribution of higher education activities in cities and the manner in which cities are connected in terms of academic linkages. This chapter reveals the spatial distribution of world cities with more higher education activities showing international standings and global connections. A four-indicator system of Globalizing Education Index, which consists of the Place Power and Network Power of cities, is proposed to measure the internationalization and connectivity of places. The spatial distribution of cities performing well in the four areas of prestigious-university standings, influential world scholars, international academic events, and global research networking suggests that decentralization of higher education activities is restricted to certain aspects, although the movement and information flows of the knowledge economy are supposedly more unrestricted under globalization. The geographical distribution of world cities with high Globalizing Education Index remains concentrated in North America with strong historical and cultural backgrounds of world academia and slightly spread to East Asia due to its strength in organizing international events. This chapter supplements existing geographical studies on higher education and proposes further research directions addressing the influence of geography and connectivity in facilitating academic activities with a global reach

Hong Kong in the Age of Sprawl: What are the Changing Urban Form and Transportation Challenges?

Session: Urban Transport in the Age of Sprawl: Part 2Urban sprawl, a common phenomenon in North America, also plays a role in Asian urban development. With a lower car ownership rate and more compact development, urban sprawl in Asian cities is worth studying from a different prospective. Urban sprawl of Western countries is generally criticized as unsustainable in terms of energy usage and traffic generation. Is there a causal relationship between urban sprawl and unsustainable transport development? Does it apply to Asian cities? This study focuses on the relative concept of urban sprawl, its characteristics and the implications on sustainable transport Hong Kong - one of the most compact cities around the world. New town development since the 1960s and its associated urban sprawl phenomenon have fundamentally changed the lifestyle and travel behaviour of many people living in the city. This study classifies the Tertiary Planning Units (TPUs), the commonly-used planning units, of Hong Kong into three types: the urban core, sprawl and rural areas and analyze the differences of travel behaviour among residents living in these three areas. Aspects of the travel behaviour examined include trip generation rates, purposes, destinations, modes and legs. An overall picture of the travel characteristics provides valuable insights on whether residents' of the sprawl area are having less sustainable transport characteristics, when compared to their counterparts. To comprehend the local sustainability issue, the transport challenges, such as public transport provisions and traffic congestion, in different parts of the sprawl areas will also be discussed

Jobs-housing balance in an era of population decentralization: An analytical framework and a case study

Despite the well-established theoretical understanding on the benefits of compact cities to the attainment of sustainable transport goals, there has been a worldwide trend of population decentralization in cities. In this paper, an analytical framework, which can be applied to other cities to quantify the potential commuting travel savings and environmental benefits of different job policies in cities having different rates and patterns of population decentralization, is presented. A case study of Hong Kong in the 1992-2002 decade is used to illustrate the analytical framework. The findings suggest that a city's population patterns did have significant implications on the commuting travel savings from alternative job relocation policies. With a dispersed population pattern, the expected environmental benefits from a job decentralization policy can be very substantial. © 2010 Elsevier Ltd.link_to_subscribed_fulltex

The Flow of International Students and Global City Network Emphasizing Regional and Global Connectivity

Conference theme: Managing International Connectivity and Diversity: Experiences of Asian World CitiesSession 2: Managing International Connectivity: Regional Hub Experience

Connectivity of Higher Education within the Global City Network: Does Transport Network Play a Role?

Conference Theme: Travel Behaviour and Societ