客座编辑：El-Sayed M. Abdelwhab, Ivan Campeotto, Sérgio Oliveira de Paula
Safe and effective vaccines are the cornerstone in our arsenal of tools for combating the global burden of infectious diseases. As illustrated in the COVID-19 pandemic, the effective utilisation of novel technologies and approaches in vaccine development can be critical in enabling the timely control and mitigation of disease outbreaks. This Collection welcomes submissions reporting new developments in vaccinology, including advances in epitope selection, antigen delivery and candidate vaccine evaluation.
Optical techniques for the recording and manipulation of neural activity in-vivo
客座编辑：Robert Krencik, Talia Lerner, Xuelin Lou
Optical methods have revolutionised the experimental measurement and control of neuronal populations. In optogenetics, the expression of light-activated opsin channels in cells enables investigators to initiate specific cellular events through the application of light as a precise activating signal. This allows us to understand the basic functioning of cells and neuronal pathways at a higher spatial and temporal resolution than before. In parallel, related optical methods have emerged that endow us with the ability to measure changes in cell activation through the release of fluorescent markers. These techniques afford either bulk or single-cell calcium imaging of neural activity with high temporal and spatial resolution in behaving animals.
Mitigation goals for the climate crisis will only be achieved with a substantial contribution from forests. To achieve this, however, we would need to increase our understanding of the dynamics, magnitude, drivers, and spatial distribution of carbon fluxes across terrestrial ecosystems, especially forests, and how they can be managed. This is essential for strategies to reduce carbon emissions and enhance carbon removals, and would also help guide climate policy, and the various actors developing nature-based solutions. This Collection aims to showcase the latest advances on Earth system models, terrestrial biosphere models, forest carbon monitoring, biomass carbon stocks and turnover, forest demography, and carbon allocation.
Since the first exploration of optical techniques in the early 2000s, the experimental tools and methods have been repeatedly refined. Indeed, it has become more and more common that both recording and manipulation of neural activity using these techniques is performed within the same animal, providing a level of control and observation of neurons in a way we have never experienced. This Collection aims to gather research using the latest optical techniques in neuroscience, and what we've learned from their application.
客座编辑：Changqing Jin（中国科学院物理研究所）, Wei Luo, Yang Song
Pressure is one of the fundamental thermodynamic variables. It affects intermolecular interactions and interatomic properties. Under extreme conditions such as high pressure, materials exhibit properties which can be remarkably different from those observed at ambient conditions. Advances in high pressure research have shown that it can be used to produce exotic materials with a range of different characteristics such as superhardness, superconductivity, and novel mechanical properties. This Collection is open to research investigating high pressure techniques, applications, and products, including methods of retaining properties gained under high pressure once the sample is returned to ambient conditions.
Social interactions are widespread among unicellular organisms. Bacteria form biofilms, allowing them to share extracellular substances, exploit new resources, and defend against protozoan predators and antimicrobial drugs. Yeast and social amoebae aggregate, forming complex cell-to-cell interactions that provide insight into the evolutionary origins of multicellularity. Even viruses interact with one another, producing public goods and cooperating to exploit hosts prudently. This Collection welcomes empirical and theoretical papers exploring the genetic and environmental factors that shape these social interactions, as well as the resulting implications for fields like biotechnology, medicine, ecology, and sociobiology.
Next generation of smart, sustainable and resilient manufacturing systems
客座编辑：David S. Cochran, Kerstin Johansen, Erwin Rauch
In addition to the increasing introduction of digitalization in manufacturing, the sustainable and resilient design of next generation manufacturing systems and value chains is one of the major challenges for the future. After years of focusing mostly on efficiency and productivity, the concept of the triple bottom line pursues the goal of achieving a balance between economic, ecological and social sustainability in manufacturing. This approach includes concepts like circular economy in manufacturing, digitalization as an enabler for sustainable manufacturing as well as human-centred manufacturing concepts and their assessment. The recent unforeseen disruptive events (e.g. Suez Canal blockade, Covid-19) have also shown how crucial it is to increase resilience in manufacturing systems to mitigate the impact of unexpected disruptions.
This Collection will gather research Articles highlighting the latest advances and technologies to facilitate resilience, circular economy and sustainable practices in the manufacturing industry.
客座编辑：Folashade Agusto, Silvana Gaudieri, Shih-Yen Lo
Primary infection typically confers some level of immunity against the infecting pathogen and similar strains. Still, pathogens are sometimes able to overcome the immune defenses of a previously infected host, leading to reinfection. Understanding the mechanisms underlying this process is crucial for public health. The prevalence of reinfection depends on a range of pathogen and host factors, including epidemiological, immunological, demographic, and genetic. In some diseases, previously infected hosts are actually more susceptible to reinfection due to antibody-mediated pathogen replication. This Collection explores the interplay between hosts and pathogens during secondary infections.
客座编辑：Renee M. Borges, Kenneth F. Haynes, Mariusz Kanturski
In recent years, it has been suggested that we are experiencing an insect apocalypse; a dramatic and ongoing decline in insect number. Indeed, some sources estimate that insect abundance may have fallen by 50% since 1970, with many species now facing extinction. Whilst it is difficult to be sure of these figures, it is clear that insects form a key part of our ecosystem – from pollinators to food source – and that we need to protect both their diversity and number, to ensure food security, and maintain the environment. It is therefore essential that we further our understanding of this phenomenon, in terms of population trends, potential drivers, and steps we may take to mitigate this decline. This Collection invites original research on the study of insect ecology, and the impact of pesticides, pollutants, and climate change on their health and number.