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Bottom-up synthesis of such molecules provides physicists with a rich playground to study newly discovered quantum effects and a means to store information at the scale of individual atoms. 

The dielectric properties of materials play a crucial role in the propagation and absorption of microwave beams employed in Magic Angle Spinning − Dynamic Nuclear Polarization (MAS-DNP) NMR experiments. Despite ongoing optimization efforts in sample preparation, routine MAS-DNP NMR applications often fall short of theoretical sensitivity limits. Offering a different perspective, we report the refractive indices and extinction coefficients of diverse materials used in MAS-DNP NMR experiments, spanning a frequency range from 70 to 960 GHz. Knowledge of their dielectric properties enables the accurate simulation of electron nutation frequencies, thereby guiding the design of more efficient hardware and sample preparation of biological or material samples. This is illustrated experimentally for four different rotor materials (sapphire, yttria-stabilized zirconia (YSZ), aluminum nitride (AlN), and SiAlON ceramics) used for DNP at 395 GHz/1H 600 MHz. Finally, electromagnetic simulations and state-of-the-art MAS-DNP numerical simulations provide a rational explanation for the observed magnetic field dependence of the enhancement when using nitroxide biradicals, offering insights that will improve MAS-DNP NMR at high magnetic fields. 

We conducted mental model interviews in Aotearoa NZ to understand perspectives of uncertainty associated with natural hazards science. Such science contains many layers of interacting uncertainties, and varied understandings about what these are and where they come from creates communication challenges, impacting the trust in, and use of, science. To improve effective communication, it is thus crucial to understand the many diverse perspectives of scientific uncertainty.Participants included hazard scientists (e.g., geophysical, social, and other sciences), professionals with some scientific training (e.g., planners, policy analysts, emergency managers), and lay public participants with no advanced training in science (e.g., journalism, history, administration, art, or other domains). We present a comparative analysis of the mental model maps produced by participants, considering individuals’ levels of training and expertise in, and experience of, science.A qualitative comparison identified increasing map organization with science literacy, suggesting greater science training in, experience with, or expertise in, science results in a more organized and structured mental model of uncertainty. There were also language differences, with lay public participants focused more on perceptions of control and safety, while scientists focused on formal models of risk and likelihood.These findings are presented to enhance hazard, risk, and science communication. It is important to also identify ways to understand the tacit knowledge individuals already hold which may influence their interpretation of a message. The interview methodology we present here could also be adapted to understand different perspectives in participatory and co-development research. 

The science associated with assessing natural hazard phenomena and the risks they pose contains many layers of complex and interacting elements, resulting in diverse sources of uncertainty. This creates a challenge for effective communication, which must consider how people perceive that uncertainty. Thus, we conducted twenty-five mental model interviews in Aotearoa New Zealand with participants ranging from scientists to policy writers and emergency managers, and through to the public. The interviews included three phases: an initial elicitation of free thoughts about uncertainty, a mental model mapping activity, and a semi-structured interview protocol to ex- plore further questions about scientific processes and their personal philosophy of science. Quali- tative analysis led to the construction of key themes, including: (a) understanding that, in addi- tion to data sources, the ‘actors’ involved can also be sources of uncertainty; (b) acknowledging that factors such as governance and funding decisions partly determine uncertainty; (c) the influ- ence of assumptions about expected human behaviours contributing to “known unknowns'; and (d) the difficulty of defining what uncertainty actually is. Participants additionally highlighted the positive role of uncertainty for promoting debate and as a catalyst for further inquiry. They also demonstrated a level of comfort with uncertainty and advocated for ‘sitting with uncertain- ty’ for transparent reporting in advice. Additional influences included: an individual's under- standing of societal factors; the role of emotions; using outcomes as a scaffold for interpretation; and the complex and noisy communications landscape. Each of these require further investiga- tion to enhance the communication of scientific uncertainty. 

Overhauser dynamic nuclear polarization (ODNP) NMR of solutions at high fields is usually mediated by scalar couplings that polarize the nuclei of heavier, electron-rich atoms. This leaves 1H-detected NMR outside the realm of such studies. This study presents experiments that deliver 1H-detected NMR experiments on relatively large liquid volumes (60 ∼ 100 μL) and at high fields (14.1 T), while relying on ODNP enhancements. To this end 13C NMR polarizations were first enhanced by relying on a mechanism that utilizes e--13C scalar coupling interactions; the nuclear spin alignment thus achieved was then passed on to neighboring 1H for observation, by a reverse INEPT scheme relying on one-bond JCH-couplings. Such 13C 1H polarization transfer ported the 13C ODNP gains into the 1H, permitting detection at higher frequencies and with higher potential sensitivities. For a model solution of labeled 13CHCl3 comixed with a nitroxide-based TEMPO derivative as polarizing agent, an ODNP enhancement factor of ca. 5x could thus be imparted to the 1H signal. When applied to bigger organic molecules like 2-13C-phenylacetylene and 13C8-indole, ODNP enhancements in the 1.2-3x range were obtained. Thus, although handicapped by the lower γ of the 13C, enhancements could be imparted on the 1H thermal acquisitions in all cases. We also find that conventional 1H–13C nuclear Overhauser enhancements (NOEs) are largely absent in these solutions due to the presence of co-dissolved radicals, adding negligible gains and playing negligible roles on the scalar e-→13C ODNP transfer. Potential rationalizations of these effects as well as extensions of these experiments, are briefly discussed.