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The paper outlines the design, prototyping, and simulation processes involved in creating a compact radio frequency (RF) backscatter communication system, powered by Organic Photovoltaic (OPV) cells. This system is integral to a mine rescue operation, particularly useful in scenarios where miners are trapped due to accidents. In such situations, a rescue drone, equipped with a searchlight and the discussed communication system, takes the lead in the assisted escape mission for miners. The drone establishes duplex communication with the miners through a battery-free, wearable transponder device. Initial experiments employing a RF backscatter testbed - which utilizes both software-defined radios and OPV cells - were conducted. These preliminary tests were crucial for assessing the conditions necessary for successful backscatter communication, as well as for evaluating the energy-harvesting performance of the system. Findings from these experiments indicate that the device can operate battery-free, powered solely by OPV cells, even under low illuminance levels of less than 75 lux. In the pursuit of crafting the device in a compact form, a co-design initiative was launched. This effort focused on developing a meander dipole antenna in tandem with the OPV cells, targeting a resonant frequency of 912 MHz. Simulation results, obtained from ANSYS HFSS, revealed significant changes in antenna impedance and S parameters yet minimal impact on the radiation pattern of the antenna with the integration of the layered OPV structure. 

Subject-verb agreement has provided critical insights into the cue-based memory retrieval system that supports language comprehension by showing that memory interference can cause erroneous agreement with non-subjects: ‘agreement attraction’. Here we ask how faithful retrieval cues are in relation to the grammar. We examine the impact of conjoined singular attractors (The advice from the doctor and the nurse. . .), which are syntactically plural but whose plurality is introduced by a vehicle, the conjunction ‘and’, that is not an unequivocal correlate of syntactic plurality. We find strong agreement attraction, which suggests that retrieval processes do not only target unequivocal morphological correlates of syn- tactic plurality. However, we also find some attraction with conjoined adjective attractors (The advice from the diligent and compassionate doctor. . .), which is compatible with a system in which an imperfect correlate of syntactic plurality, like the word ‘and’, can become associated with the plural retrieval cue due to frequent co-occurrence with the actual target feature.