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In recent years, the concentration of precious metals and hazardous pollutants in discarded consumer-grade computer enclosures has increased significantly, coinciding with e-waste generation in Asia reaching approximately 30 million tons annually. However, the high cost and low efficiency of manual disassembly present substantial obstacles to the effective recycling of such enclosures. Robotic disassembly has emerged as a promising alternative. To enable accurate acquisition of three-dimensional (3D) geometric data for robotic operations, we propose a 3D measurement method based on multi-color high dynamic range imaging. This method employs a seven-color illumination strategy and exploits the spectral response characteristics of a color camera to different wavelengths, effectively mitigating the reconstruction errors caused by overexposure on highly reflective surfaces—an issue common in traditional techniques. The proposed approach provides complete and reliable 3D morphological information to support robotic arm manipulation. Experimental results confirm that the method accurately captures the 3D profiles of reflective components such as CPUs and motherboards. Moreover, validation across computer enclosures of different brands and form factors demonstrates the method’s robustness and practical applicability in a wide range of e-waste disassembly scenarios. 

Abstract Key functions of antibodies, such as viral neutralisation, depend on high-affinity binding. However, viral neutralisation poorly correlates with antigen affinity for reasons that have been unclear. Here, we use a new mechanistic model of bivalent binding to study  >45 patient-isolated IgG1 antibodies interacting with SARS-CoV-2 RBD surfaces. The model provides the standard monovalent affinity/kinetics and new bivalent parameters, including the molecular reach: the maximum antigen separation enabling bivalent binding. We find large variations in these parameters across antibodies, including reach variations (22–46 nm) that exceed the physical antibody size (~15 nm). By using antigens of different physical sizes, we show that these large molecular reaches are the result of both the antibody and antigen sizes. Although viral neutralisation correlates poorly with affinity, a striking correlation is observed with molecular reach. Indeed, the molecular reach explains differences in neutralisation for antibodies binding with the same affinity to the same RBD-epitope. Thus, antibodies within an isotype class binding the same antigen can display differences in molecular reach, substantially modulating their binding and functional properties. 

Repetitive subtasks of locomotion are offloaded from a conventional computer-actuator-sensor set-up to automatic mechanical processes. The subtasks considered are: (1) when out-of-contact with the environment, move a leg to a ready position in preparation for step contact, and (2) when contact is detected, push off the ground. Using conventional closed-loop control, subtask (1) would be accomplished by programming logic and a feedback loop onto a computer-motor-encoder system, and subtask (2) would be accomplished by sensing contact, then commanding the leg motor to push-off via programmed computer logic. We demonstrate how to transition this programmed logic from a computer processor to a mechanical processor. The mechanical processor performs preprogrammed actions based on combinations of states of components, some of which are internal and some that interact with the environment. Because signals are not digital, but rather mechanical quantities of energy, position, and force; transitioning to a mechanical processor enables a third subtask not possible by the computer alone: that is, (3) the accumulation of elastic energy while out-of-contact with the environment, and its automatic release upon contact for a more powerful push-off motion. Migrating processing out of the computer reduces the number of transduction steps, allows for faster responses to dynamic events, and instantiates a high-powered reflex triggered by ground contact. To illustrate these benefits, a robot with built-in onboard mechanical processing is compared to a conventional robot with logic executed by an offboard computer. 

Abstract Transient plant enzyme complexes formed via protein-protein interactions (PPIs) play crucial regulatory roles in secondary metabolism. Complexes assembled on cytochrome P450s (CYPs) are challenging to characterize metabolically due to difficulties in decoupling the PPIs’ metabolic impacts from the CYPs’ catalytic activities. Here, we developed a yeast-based synthetic biology approach to elucidate the metabolic roles of PPIs between a soybean-derived CYP, isoflavone synthase (GmIFS2), and other enzymes in isoflavonoid metabolism. By reconstructing multiple complex variants with an inactive GmIFS2 in yeast, we found that GmIFS2-mediated PPIs can regulate metabolic flux between two competing pathways producing deoxyisoflavonoids and isoflavonoids. Specifically, GmIFS2 can recruit chalcone synthase (GmCHS7) and chalcone reductase (GmCHR5) to enhance deoxyisoflavonoid production or GmCHS7 and chalcone isomerase (GmCHI1B1) to enhance isoflavonoid production. Additionally, we identified and characterized two novel isoflavoneO-methyltransferases interacting with GmIFS2. This study highlights the potential of yeast synthetic biology for characterizing CYP-mediated complexes.