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Obtaining insight into the constituents of dark matter and their interactions with normal matter has inspired a wide range of experimental efforts. Several approaches, particularly those involving searches for ultralight bosonic dark matter (UBDM) fields, involve the use of quantum systems or measurements performed at the limits imposed by quantum mechanics. While a classical treatment of UBDM and its detectors is satisfactory, a fully quantum description would assist in developing future detection strategies. Here, we present an open quantum systems approach that accomplishes this while providing intuition into the quantum nature of the detection process itself. Furthermore, we apply the quantum theory of optical coherence to characterize the statistical properties of the UBDM field. Using representative examples, we show that this theoretical treatment has implications in uncovering signatures of the cosmological production mechanism of the UBDM field and its galactic merger history. By adapting tools from quantum optics, this work will help facilitate the creation of novel methods to extract astrophysically relevant information from correlation measurements. Published by the American Physical Society2025 

ABSTRACT Predation can alter diverse ecological processes, including host–parasite interactions. Selective predation, whereby predators preferentially feed on certain prey types, can affect prey density and selective pressures. Studies on selective predation in infected populations have primarily focused on predators preferentially feeding on infected prey. However, there is substantial evidence that some predators preferentially consume uninfected individuals. Such different strategies of prey selectivity likely modulate host–parasite interactions, changing the fitness payoffs both for hosts and their parasites. Here we investigated the effects of different types of selective predation on infection dynamics and host evolution. We used a host–parasite system in the laboratory (Daphnia dentifera infected with the horizontally transmitted fungus,Metschnikowia bicuspidata) to artificially manipulate selective predation by removing infected, uninfected, or randomly selected prey over approximately 8–9 overlapping generations. We collected weekly data on population demographics and host infection and measured susceptibility from a subset of the remaining hosts in each population at the end of the experiment. After 6 weeks of selective predation pressure, we found no differences in host abundance or infection prevalence across predation treatments. Counterintuitively, populations with selective predation on infected individuals had a higher abundance of infected individuals than populations where either uninfected or randomly selected individuals were removed. Additionally, populations with selective predation for uninfected individuals had a higher proportion of individuals infected after a standardized exposure to the parasite than individuals from the two other predation treatments. These results suggest that selective predation can alter the abundance of infected hosts and host evolution. 

This study explores the innovative use of carbon matrices in the synthesis of magnetic nanographite, layered graphene stacks and graphene coated magnetic nanoparticles, with a focus on their morphological, structural, and magnetic prop-erties. To obtain a deeper insight into the influences of impurities in the graphene matrices on the magnetic properties of synthesized by pyrolysis, the two different metal free modifications of porphyrin such as tetraphenyl porphyrin (TPP) and tetra(4-carboxyphenyl) porphyrin (TCPP) with oxygen content (radical) were synthesized by subsequential post annealing with oxygen, argon and nitrogen, to characterize and investigate the role of oxygen and nitrogen content in graphene environment. The research highlights the significance of porphyrin and phthalocyanine metal free precursors and their metal counterparts for use as carbon matrices, examining their unique characteristics and applications in nanoparticle synthesis by sequential annealing. For example, the magnetization figure below for TPP indicates that the samples are diamagnetic at relatively high temperatures and large magnetic fields. Annealing at 150 °C for 180 min, specifically, for oxygen, it increases paramagnetic behavior and saturation. As for nitrogen, it increases coercivity. Employing advanced characterization techniques such as powder x-ray diffraction (PXRD), we analyzed the graphitization and porosity effects and layer sizes of nanographite and their impact on magnetic properties. A novel algorithm, integrating node extraction and 2D Gaussian mapping, is developed to enhance the accuracy of morphological analysis. Our findings reveal the critical role of graphene, and role of oxygen and nitrogen impurities in influencing the magnetic behavior of metal free carbon matrices and embedded nanoparticles, providing valuable insights into the design and development of advanced magnetic nanomaterials.