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Background: Biologics is an exciting and growing area of medicine. Within the larger field of biologics, the use of viral vectors and virus-like particles (VLPs) is increasingly common, making it crucial to develop innovative and practical unit operations for the related purification process. Objective: Some scientists and engineers propose that membrane-based downstream virus purification (MVP) platforms would allow for more scalable and cost-effective production of these critical particles. However, the so-cial, political, and ethical implications of these advancements remain largely unex-plored. This paper aims to explore various pivotal facets of MVP technology govern-ance and regulations within the U.S. context, including (1) government policy ar-rangements related to the implementation of the technologies, (2) stakeholder atti-tudes, policy preferences, and behaviors, and (3) the fundamental factors that shape these attitudes, policy preferences, and behaviors. Methods: In doing so, we analyze publicly available federal and state government documents pertaining to biomanu-facturing, healthcare, and legislative attempts. Additionally, we will perform a stake-holder analysis on relevant industries, healthcare service providers, and recipients. Conclusions: Our goal is to outline the socio-political, ethical, and regulatory factors pertaining to the regulation and governance of these technologies. 

The Planetary Boundary Layer Height (PBLH) significantly impacts weather, climate, and air quality. Understanding the global diurnal variation of the PBLH is particularly challenging due to the necessity of extensive observations and suitable retrieval algorithms that can adapt to diverse thermodynamic and dynamic conditions. This study utilized data from the Cloud-Aerosol Transport System (CATS) to analyze the diurnal variation of PBLH in both continental and marine regions. By leveraging CATS data and a modified version of the Different Thermo-Dynamics Stability (DTDS) algorithm, along with machine learning denoising, the study determined the diurnal variation of the PBLH in continental mid-latitude and marine regions. The CATS DTDS-PBLH closely matches ground-based lidar and radiosonde measurements at the continental sites, with correlation coefficients above 0.6 and well-aligned diurnal variability, although slightly overestimated at nighttime. In contrast, PBLH at the marine site was consistently overestimated due to the viewing geometry of CATS and complex cloud structures. The study emphasizes the importance of integrating meteorological data with lidar signals for accurate and robust PBLH estimations, which are essential for effective boundary layer assessment from satellite observations. 

The spin- $1/2$kagome Heisenberg antiferromagnets are believed to host exotic quantum entangled states. Recently, the reports of $1/9$magnetization plateau and magnetic oscillations in a kagome antiferromagnet ${\mathrm{YCu}}_3{\left(\mathrm{OH}\right)}_6{\mathrm{Br}}_2\left[{\text{Br}}_x{\left(\mathrm{OH}\right)}_{1-x}\right]$(YCOB) have made this material a promising candidate for experimentally realizing quantum spin liquid states. Here, we present measurements of the specific heat $C_p$in YCOB in high magnetic fields (up to 41.5 T) down to 0.46 K, and the $1/9$plateau feature has been confirmed. Moreover, the temperature dependence of $C_p/T$in the vicinity of $1/9$plateau region can be fitted by a linear in $T$term which indicates the presence of a Dirac spectrum, together with a constant term, which indicates a finite density of states contributed by other spinon Fermi surfaces. Surprisingly, the constant term is highly anisotropic in the direction of the magnetic field. Additionally, we observe a double-peak feature near 30 T above the $1/9$plateau which is another hallmark of fermionic excitations in the specific heat. This combination of gapless behavior and the double-peak structure strongly suggests that the $1/9$plateau in YCOB is nontrivial and hosts fermionic quasiparticles. 

Cai and Hemachandra used iterative constant-setting to prove that Few ⊆ ⊕ P (and thus that Few P ⊆ ⊕P). In this article, we note that there is a tension between the nondeterministic ambiguity of the class one is seeking to capture, and the density (or, to be more precise, the needed “nongappiness”) of the easy-to-find “targets” used in iterative constant-setting. In particular, we show that even less restrictive gap-size upper bounds regarding the targets allow one to capture ambiguity-limited classes. Through a flexible, metatheorem-based approach, we do so for a wide range of classes including the logarithmic-ambiguity version of Valiant’s unambiguous nondeterminism class UP. Our work lowers the bar for what advances regarding the existence of infinite, P-printable sets of primes would suffice to show that restricted counting classes based on the primes have the power to accept superconstant-ambiguity analogues of UP. As an application of our work, we prove that the Lenstra–Pomerance–Wagstaff Conjecture implies that all\((\mathcal {O}(1) + \log \log n)\)-ambiguity NP sets are in the restricted counting class RC_PRIMES. 

A localized Zeeman field, intensified at heterostructure interfaces, could play a crucial role in a broad area including spintronics and unconventional superconductors. Conventionally, the generation of a local Zeeman field is achieved through magnetic exchange coupling with a magnetic material. However, magnetic elements often introduce defects, which could weaken or destroy superconductivity. Alternatively, the coupling between a superconductor with strong spin-orbit coupling and a nonmagnetic chiral material could serve as a promising approach to generate a spin-active interface. Here, we leverage an interface superconductor, namely, induced superconductivity in noble metal surface states, to probe the spin-active interface. Our results unveil an enhanced interface Zeeman field, which selectively closes the surface superconducting gap while preserving the bulk superconducting pairing. The chiral material, i.e., trigonal tellurium, also induces Andreev bound states (ABS) exhibiting spin polarization. The field dependence of ABS manifests a substantially enhanced interface Landég-factor (g_eff~ 12), thereby corroborating the enhanced interface Zeeman energy. 

Abstract Measuring, reporting, and verification (MRV) of ocean-based carbon dioxide removal (CDR) presents challenges due to the dynamic nature of the ocean and the complex processes influencing marine carbonate chemistry. Given these challenges, finding the optimal sampling strategies and suite of parameters to be measured is a timely research question. While traditional carbonate parameters such as total alkalinity (TA), dissolved inorganic carbon (DIC), pH, and seawater pCO2 are commonly considered, exploring the potential of carbon isotopes for quantifying additional CO2 uptake remains a relatively unexplored research avenue. In this study, we use a coupled physical-biogeochemical model of the California Current System (CCS) to run a suite of Ocean Alkalinity Enhancement (OAE) simulations. The physical circulation for the CCS is generated using a nested implementation of the Regional Ocean Modeling System (ROMS) with an outer domain of 1/10 ̊ (~10 km) and an inner domain of 1/30 ̊ (~3 km) resolution. The biogeochemical model, NEMUCSC, is a customized version of the North Pacific Ecosystem Model for Understanding Regional Oceanography (NEMURO) that includes carbon cycling and carbon isotopes. The CCS is one of four global eastern boundary upwelling systems characterized by high biological activity and CO2 concentrations. Consequently, the CCS represents an essential test case for investigating the efficacy and potential side effects of OAE deployments. The study aims to address two key questions: (1) the relative merit of OAE to counter ocean acidification versus the additional sequestration of CO2 from the atmosphere, and (2) the footprint of potentially harmful seawater chemistry adjacent to OAE deployments. We plan to leverage these high-resolution model results to competitively evaluate different MRV strategies, with a specific focus on analyzing the spatiotemporal distribution of carbon isotopic signatures following OAE. In this talk, we will showcase our initial results and discuss challenges in integrating high-resolution regional modeling into models of the global carbon cycle. More broadly, this work aims to provide insights into the plausibility of OAE as a climate solution that maintains ocean health and to inform accurate quantification of carbon uptake for MRV purposes. https://agu.confex.com/agu/OSM24/prelim.cgi/Paper/1491096 

Abstract Measuring, reporting, and verification (MRV) of ocean-based carbon dioxide removal (CDR) presents challenges due to the dynamic nature of the ocean and the complex processes influencing marine carbonate chemistry. Given these challenges, finding the optimal sampling strategies and suite of parameters to be measured is a timely research question. While traditional carbonate parameters such as total alkalinity (TA), dissolved inorganic carbon (DIC), pH, and seawater pCO2 are commonly considered, exploring the potential of carbon isotopes for quantifying additional CO2 uptake remains a relatively unexplored research avenue. In this study, we use a coupled physical-biogeochemical model of the California Current System (CCS) to run a suite of Ocean Alkalinity Enhancement (OAE) simulations. The physical circulation for the CCS is generated using a nested implementation of the Regional Ocean Modeling System (ROMS) with an outer domain of 1/10 ̊ (~10 km) and an inner domain of 1/30 ̊ (~3 km) resolution. The biogeochemical model, NEMUCSC, is a customized version of the North Pacific Ecosystem Model for Understanding Regional Oceanography (NEMURO) that includes carbon cycling and carbon isotopes. The CCS is one of four global eastern boundary upwelling systems characterized by high biological activity and CO2 concentrations. Consequently, the CCS represents an essential test case for investigating the efficacy and potential side effects of OAE deployments. The study aims to address two key questions: (1) the relative merit of OAE to counter ocean acidification versus the additional sequestration of CO2 from the atmosphere, and (2) the footprint of potentially harmful seawater chemistry adjacent to OAE deployments. We plan to leverage these high-resolution model results to competitively evaluate different MRV strategies, with a specific focus on analyzing the spatiotemporal distribution of carbon isotopic signatures following OAE. In this talk, we will showcase our initial results and discuss challenges in integrating high-resolution regional modeling into models of the global carbon cycle. More broadly, this work aims to provide insights into the plausibility of OAE as a climate solution that maintains ocean health and to inform accurate quantification of carbon uptake for MRV purposes. https://agu.confex.com/agu/fm23/meetingapp.cgi/Paper/1437343 

Abstract In this work, we utilize a transect of core top, mid- to late Holocene, sediments from the Eastern Siberian Sea to the central Arctic Ocean, spanning gradients in upper-ocean water column properties, to examine regional planktic foraminiferal species abundances and geochemistry. We present species- and morphotype-specific foraminiferal assemblages at these sites and stable isotope analyses of neogloboquadrinids. We find little variation in planktic species populations, and only small variations in N. pachyderma morphotype distributions, between sites. Spatial averages of N. pachyderma morphotype and N. incompta δ18O values show no significant differences, suggesting a similar calcification depth for all morphotypes of N. pachyderma and N. incompta across our sites, which we estimate to be between ∼ 50–150 m. Values of δ18O of a group of unencrusted specimens delineate a shallower calcification habitat. Neogloboquadrina pachyderma-2 Mg/Ca values yield temperatures outside the range of observations using available calibration equations, pointing toward the need for more Arctic-specific Mg/Ca-temperature calibrations.