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Abstract Developing programmable bacterial cell-cell adhesion is of significant interest due to its versatile applications. Current methods that rely on presenting cell adhesion molecules (CAMs) on bacterial surfaces are limited by the lack of a generalizable strategy to identify such molecules targeting bacterial membrane proteins in their natural states. Here, we introduce a whole-cell screening platform designed to discover CAMs targeting bacterial membrane proteins within a synthetic bacteria-displayed nanobody library. Leveraging the potency of the bacterial type IV secretion system—a contact-dependent DNA delivery nanomachine—we have established a positive feedback mechanism to selectively enrich for bacteria displaying nanobodies that target antigen-expressing cells. Our platform successfully identified functional CAMs capable of recognizing three distinct outer membrane proteins (TraN, OmpA, OmpC), demonstrating its efficacy in CAM discovery. This approach holds promise for engineering bacterial cell-cell adhesion, such as directing the antibacterial activity of programmed inhibitor cells toward target bacteria in mixed populations.

Ecosystem services, such as crop provision, carbon storage, water retention, and nutrient retention, are crucial for sustainable agriculture and local participation. Assessing and mapping these services is crucial for promoting sustainable agriculture and ensuring the active involvement of local communities. However, accurately estimating the values of agricultural ecosystem services is challenging due to the lack of accurate data and an effective economic decision-making system. To address these issues, this study combines field data and modeling approaches to quantify the physical and monetary values of cropland ecosystem services in Yunlin County, Taiwan. The results indicated that the service of crop provision (rice) ranges from 7.96 to 9.70 tonnes ha−1 yr−1, valued at approximately US$7,710 to US$10,650 ha−1 yr−1. The service of soil carbon storage exhibits a carbon stock ranging from 38.2 to 51.9 tonnes of carbon ha−1 yr−1, valued at approximately US$13,150 to US$17,890 ha−1 yr−1. Water retention services retain around 5,380 m3 ha−1 yr−1, valued at approximately US$5,530 ha−1 yr−1. Nutrient retention services retain 1.65 kg ha−1 yr−1 of phosphorus and 30.5 kg ha−1 yr−1 of nitrogen per year, valued at approximately US$60 ha−1 yr−1. We also found that employing the field data approach unveils a higher total ecosystem service value of US$34,105 per hectare per year, which is 28.5 % greater than the value derived from the modeling approach. The results provide insights into enhancing local participation in sustainable soil and agricultural resource management. The quantification of physical and monetary values of ecosystem services can support informed decision-making and promote local participation in sustainable soil and agricultural resource management.

We investigate the spectral shift known as the collective Lamb shift in forward scattering for a cold dense atomic cloud. The shift results from resonant dipole–dipole interaction mediated by real and virtual photon exchange, forming many-body states displaying various super- and subradiant behaviour. However, the scattering spectrum reflects the overall contributions from these states but also averages out the radiative details associated with the underlying spin orders, causing ambiguity in determination and raising controversy on the scaling property of this shift. We employ a Monte–Carlo simulation to study how the collective states contribute to emission. We thus distinguish two kinds of collective shift that follow different scaling laws. One results from dominant occupation of the near-resonant collective states. This shift is usually small and insensitive to the density or the number of participating atoms. The other comes from large spatial correlation of dipoles, associated with the states of higher degree of emission. This corresponds to larger collective shift that is approximately linearly dependent on the optical depth. We further demonstrate that the spatial spin order plays an essential role in superradiant emission. Our analysis provides a novel perspective for understanding collective scattering and cooperative effects.