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Item Metadata only Protein-induced modifications in crystal morphology of a hydrogen-bonded organic framework(Royal Society of Chemistry (RSC), 2023) Flint, K.L.; Evans, J.D.; Carraro, F.; Renner, S.; Linder-Patton, O.M.; Amenitsch, H.; Falconer, R.J.; White, N.G.; Sumby, C.J.; Falcaro, P.; Doonan, C.J.In this work, we studied the encapsulation of a range of proteins in a hydrogen-bonded organic framework (HOF) comprised of a tetraamidinium cation and diazobenzene-based dicarboxylate anion. We explore the use of external stimuli: light and temperature to modulate HOF crystal growth and size. In particular, we found photo-isomerisation can be used to control the concentration of the trans-azobenzene building block that contributes to HOF formation. When HOF growth was slowed sufficiently, deformation of the crystals and ultimately multicrystal aggregates were observed in the presence of some proteins. We propose that the extent of crystal deformation, consistent with better protein association, may be governed by differences in the type and strength of interactions between proteins and the surface of the growing HOF crystals.Item Open Access Non-equilibrium molecular dynamics of steady-state fluid transport through a 2D membrane driven by a concentration gradient(American Institute of Physics, 2023) Rankin, D.J.; Huang, D.M.We use a novel non-equilibrium algorithm to simulate steady-state fluid transport through a two-dimensional (2D) membrane due to a concentration gradient by molecular dynamics (MD) for the first time. We confirm that, as required by the Onsager reciprocal relations in the linear-response regime, the solution flux obtained using this algorithm agrees with the excess solute flux obtained from an established non-equilibrium MD algorithm for pressure-driven flow. In addition, we show that the concentration-gradient-driven solution flux in this regime is quantified far more efficiently by explicitly applying a transmembrane concentration difference using our algorithm than by applying Onsager reciprocity to pressure-driven flow. The simulated fluid fluxes are captured with reasonable quantitative accuracy by our previously derived continuum theory of concentration-gradient-driven fluid transport through a 2D membrane [D. J. Rankin, L. Bocquet, and D. M. Huang, J. Chem. Phys. 151, 044705 (2019)] for a wide range of solution and membrane parameters, even though the simulated pore sizes are only several times the size of the fluid particles. The simulations deviate from the theory for strong solute-membrane interactions relative to thermal energy, for which the theoretical approximations breakdown. Our findings will be beneficial for a molecular-level understanding of fluid transport driven by concentration gradients through membranes made from 2D materials, which have diverse applications in energy harvesting, molecular separations, and biosensing.Item Open Access Controlled formation of gold nanoparticles with tunable plasmonic properties in tellurite glass(Springer Science and Business Media LLC, 2023) Wei, Y.; Zhao, J.; Fuhrmann, S.; Sajzew, R.; Wondraczek, L.; Ebendorff-Heidepriem, H.Silicate glasses with metallic nanoparticles (NPs) have been of intense interest in art, science and technology as the plasmonic properties of these NPs equip glass with light modulation capability. The so-called striking technique has enabled precise control of the in situ formation of metallic NPs in silicate glasses for applications from coloured glasses to photonic devices. Since tellurite glasses exhibit the unique combination of comparably easy fabrication, low phonon energy, wide transmission window and high solubility of luminescent rare earth ions, there has been a significant amount of work over the past two decades to adapt the striking technique to form gold or silver NPs in tellurite glasses. Despite this effort, the striking technique has remained insufficient for tellurite glasses to form metal NPs suitable for photonic applications. Here, we first uncover the challenges of the traditional striking technique to create gold NPs in tellurite glass. Then, we demonstrate precise control of the size and concentration of gold NPs in tellurite glass by developing new approaches to both steps of the striking technique: a controlled gold crucible corrosion technique to incorporate gold ions in tellurite glass and a glass powder reheating technique to subsequently transform the gold ions to gold NPs. Using the Mie theory, the size, size distribution and concentration of the gold NPs formed in tellurite glass are determined from the plasmonic properties of the NPs. This fundamental research provides guidance for designing and manipulating the plasmonic properties in tellurite glass for photonics research and applications.Item Open Access The effect of in-situ metasomatism on the electrical resistivity of the lower crust(Elsevier BV, 2023) Jennings, S.; Hasterok, D.; Hand, M.; Bhowany, K.Improved estimates of composition and temperature in the lower crust are vital in characterising crustal rheology and better understanding tectonic processes. Fluids introduced into the lower crust during collisional events leave behind large domains of metasomatised crust which are long-lived and should be observable via magnetotelluric sounding. With this in mind, the electrical conductivity of a subduction-related eclogite and its anhydrous, anorthositic granulite protolith were experimentally determined at atmospheric pressure and lower crustal temperatures (773–1123 K). Complex impedance spectra were collected between 20 Hz and 2 MHz while oxygen fugacity was controlled about the quartz-fayalite-magnetite (QFM) buffer using a CO:CO2 gas mix. At <1000 K, both samples are characterised by impurity conduction with low observed activation enthalpies of 0.48 ± 0.03 eV and 0.39 ± 0.02 eV for the granulite and eclogite respectively. High temperature data from the granulite (>1000 K) indicates a switch to small polarons with an activation enthalpy of 1.02 ± 0.02 eV. Results indicate that conversion of Fe-poor mafic granulite to eclogite does not enhance conductivity at lower crustal temperatures. Comparisons with previous experiments reveal a much stronger relationship between conductivity and FeOT than previously anticipated. Modelling indicates that an increase in FeOT of 2 wt% is equivalent to a temperature increase of 100 K and reasonable variations in FeOT in the lower crust may account for ~4 orders of magnitude variation in conductivity. Elevated FeOT up to 20 wt% may enhance conductivity to ~100 S m− 1 at a moderate 873 K. A system of linear equations is derived to estimate iron content, electrical conductivity or temperature within dry, mafic lower crust. For the temperature range 773–973 K, conductivity may be predicted to within 0.16 log units using log σ(T,FeOT) = 0.006 T + 0.3FeOT − 11.35. Under the same conditions, FeOT may be predicted to within 0.51 wt% using FeOT (T,σ) = 37–0.0193 T + 3.24 log σ. Finally, lower crustal temperatures may be estimated to within 24 K using T(FeOT,σ) = 1728 − 42FeOT + 139 log σ.Item Metadata only Understanding the structural landscape of Mn-based MOFs formed with hinged pyrazole carboxylate linkers(Royal Society of Chemistry (RSC), 2023) Smernik, J.F.; Gimeno-Fonquernie, P.; Albalad, J.; Jones, T.S.; Young, R.J.; Champness, N.R.; Doonan, C.J.; Evans, J.D.; Sumby, C.J.Metal–organic frameworks (MOFs) capable of post-synthetic metalation (PSMet) have garnered significant interest as supports for catalytic metals. The Mn-based MOF, MnMOF-1 ([Mn3(L2Me)3] where L2Me = bis- (4-carboxyphenyl-3,5-dimethylpyrazolyl)methane), has been an exemplar for studying PSMet. Herein we investigate the synthesis of Mn-based MOFs from related flexible ditopic pyrazole carboxylate links, along with the formation of MOFs with similar tetratopic hinged linkers. We show for the first time that MnMOF-1 is likely a kinetic or metastable phase and a newly identified 2D layered material (MnMOF-2D) is the thermodynamically favoured product for this metal–linker combination. Formation of a MnMOF-1 structure with shorter linkers is thwarted by steric clashes that preclude the formation of the Mn3 cluster. This observation prompted the use of density functional theory (DFT) simulations that showed the target material to be very dense, highly strained and thereby energetically unfavourable, but potentially, a hypothetical MnMOF-1 structure with a longer phenylethynyl spacer would be energetically feasible. Finally, the predominance of 2D MOFs formed with shorter flexible links encouraged us to use tetratopic hinged linkers to form 3D frameworks, which was vindicated by the successful synthesis of two new porous 3D Mn-based MOFs, MnMOF-L4 and MnMOF-L5. These results highlight that reticular synthesis of MOFs formed with flexible, non-linear linkers is challenging.Item Metadata only Towards multimodal cellular imaging: optical and X-ray fluorescence(Royal Society of Chemistry (RSC), 2023) Graziotto, M.E.; Kidman, C.J.; Adair, L.D.; James, S.A.; Harris, H.H.; New, E.J.Imaging techniques permit the study of the molecular interactions that underlie health and disease. Each imaging technique collects unique chemical information about the cellular environment. Multimodal imaging, using a single probe that can be detected by multiple imaging modalities, can maximise the information extracted from a single cellular sample by combining the results of different imaging techniques. Of particular interest in biological imaging is the combination of the specificity and sensitivity of optical fluorescence microscopy (OFM) with the quantitative and element-specific nature of X-ray fluorescence microscopy (XFM). Together, these techniques give a greater understanding of how native elements or therapeutics affect the cellular environment. This review focuses on recent studies where both techniques were used in conjunction to study cellular systems, demonstrating the breadth of biological models to which this combination of techniques can be applied and the potential for these techniques to unlock untapped knowledge of disease states.Item Open Access A Lantern-Shaped Pd(II) Cage Constructed from Four Different Low Symmetry Ligands with Positional and Orientational Control: an Ancillary Pairings Approach(Wiley, 2023) Preston, D.; Evans, J.D.One of the key challenges of metallosupramolecular chemistry is to maintain the ease of selfassembly but, at the same time, create structures of increasingly high levels of complexity. In palladium(II) quadruply stranded lantern-shaped cages, this has been achieved through either 1) the formation of heteroleptic (multi-ligand) assemblies, or 2) homoleptic assemblies from low-symmetry ligands. Heteroleptic cages formed from low-symmetry ligands, a hybid of these two approaches, would add an additional rich level of complexity but no examples of these have been reported. Here we use a system of ancillary complementary ligand pairings at the termini of cage ligands to target heteroleptic assemblies: these complementary pairs can only interact (through coordination to a single Pd(II) metal ion) between ligands in a cis position on the cage. Complementarity between each pair (and orthogonality to other pairs) is controlled by denticity (tridentate to monodentate or bidentate to bidentate) and/or hydrogen-bonding capability (AA to DD or AD to DA). This allows positional and orientational control over ligands with different ancillary sites. By using this approach, we have successfully used low-symmetry ligands to synthesise complex heteroleptic cages, including an example with four different low-symmetry ligands.Item Open Access Challenges of polymer‐based pH sensing in soil(Wiley, 2024) Ebadati, E.; Switalska, E.; Lombi, E.; Warren‐Smith, S.C.; Evans, D.It is well established that plants need a range of soil nutrients to grow. In farming, these nutrients are generally added to the soil in the form of fertilizers. However, depending on the soil conditions (such as temperature, water content, pH, and soil type), nutrients may not be in the right form for plant uptake. Determining the availability of nutrients in the soil for plant growth is therefore critical for the yield and productivity of modern farming. A considerable amount of research and knowledge has been developed that shows the importance of the soil pH on the availability (or not) of nutrients. Furthermore, pH plays a crucial role in controlling the availability of potential toxic elements, such as aluminum and manganese. This review article discusses recent research aimed at real‐time and continuous soil pH measurement in‐situ. More specifically, it focuses on the development of polymer materials that will ultimately enable pH measurements for the specific application of in‐ground pH sensing. Given the breadth of the polymeric sensor research field, this review has a narrowed focus on optical and electrochemical transduction methods.Item Open Access Large-area epitaxial growth of InAs nanowires and thin films on hexagonal boron nitride by metal organic chemical vapor deposition(IOP Publishing, 2023) Vilasam, A.G.S.; Adhikari, S.; Gupta, B.; Balendhran, S.; Higashitarumizu, N.; Tournet, J.; Li, L.; Javey, A.; Crozier, K.B.; Karuturi, S.; Jagadish, C.; Tan, H.H.Large-area epitaxial growth of III-V nanowires and thin films on van der Waals substrates is key to developing flexible optoelectronic devices. In our study, large-area InAs nanowires and planar structures are grown on hexagonal boron nitride templates using metal organic chemical vapor deposition method without any catalyst or pre-treatments. The effect of basic growth parameters on nanowire yield and thin film morphology is investigated. Under optimised growth conditions, a high nanowire density of 2.1×109cm-2is achieved. A novel growth strategy to achieve uniform InAs thin film on h-BN/SiO2/Si substrate is introduced. The approach involves controlling the growth process to suppress the nucleation and growth of InAs nanowires, while promoting the radial growth of nano-islands formed on the h-BN surface. A uniform polycrystalline InAs thin film is thus obtained over a large area with a dominant zinc-blende phase. The film exhibits near-band-edge emission at room temperature and a relatively high Hall mobility of 399 cm-2/(Vs). This work suggests a promising path for the direct growth of large-area, low-temperature III-V thin films on van der Waals substrates.Item Open Access From biomolecules to biogeochemistry: Exploring the interaction of an indigenous bacterium with gold(Elsevier BV, 2023) Sanyal, S.K.; Pukala, T.; Mittal, P.; Reith, F.; Brugger, J.; Etschmann, B.; Shuster, J.Specialised microbial communities colonise the surface of gold particles in soils/sediments, and catalyse gold dissolution and re-precipitation, thereby contributing to the environmental mobility and toxicity of this ‘inert’ precious metal. We assessed the proteomic and physiological response of Serratia proteamaculans, the first metabolically active bacterium enriched and isolated directly from natural gold particles, when exposed to toxic levels of soluble Au3+ (10 μM). The results were compared to a metal-free blank, and to cultures exposed to similarly toxic levels of soluble Cu2+ (0.1 mM); Cu was chosen for comparison because it is closely associated with Au in nature due to similar geochemical properties. A total of 273 proteins were detected from the cells that experienced the oxidative effects of soluble Au, of which 139 (51%) were upregulated with either sole expression (31%) or had synthesis levels greater than the Au-free control (20%). The majority (54%) of upregulated proteins were functionally different from up-regulated proteins in the bacteria-copper treatment. These proteins were related to broad functions involving metabolism and biogenesis, followed by cellular process and signalling, indicating significant specificity for Au. This proteomic study revealed that the bacterium upregulates the synthesis of various proteins related to oxidative stress response (e.g., Monothiol-Glutaredoxin, Thiol Peroxidase, etc.) and cellular damage repair, which leads to the formation of metallic gold nanoparticles less toxic than ionic gold. Therefore, indigenous bacteria may mediate the toxicity of Au through two different yet simultaneous processes: i) repairing cellular components by replenishing damaged proteins and ii) neutralising reactive oxygen species (ROS) by up-regulating the synthesis of antioxidants. By connecting the fields of molecular bacteriology and environmental biogeochemistry, this study is the first step towards the development of biotechnologies based on indigenous bacteria applied to gold bio-recovery and bioremediation of contaminated environments.Item Metadata only Enhanced Bioactivity of Enzyme/MOF Biocomposite via Host Framework Engineering(ACS Publications, 2023) Liang, W.; Flint, K.; Yao, Y.; Wu, J.; Wang, L.; Doonan, C.; Huang, J.This study reports the successful development of a sustainable synthesis protocol for a phase-pure metal azolate framework (MAF-6) and its application in enzyme immobilization. An esterase@MAF-6 biocomposite was synthesized, and its catalytic performance was compared with that of esterase@ZIF-8 and esterase@ZIF-90 in transesterification reactions. Esterase@MAF-6, with its large pore aperture, showed superior enzymatic performance compared to esterase@ZIF-8 and esterase@ZIF-90 in catalyzing transesterification reactions using both n-propanol and benzyl alcohol as reactants. The hydrophobic nature of the MAF-6 platform was shown to activate the immobilized esterase into its open-lid conformation, which exhibited a 1.5- and 4-times enzymatic activity as compared to free esterase in catalyzing transesterification reaction using n-propanol and benzyl alcohol, respectively. The present work offers insights into the potential of MAF-6 as a promising matrix for enzyme immobilization and highlights the need to explore MOF matrices with expanded pore apertures to broaden their practical applications in biocatalysis.Item Open Access Anisotropic molecular coarse-graining by force and torque matching with neural networks(AIP Publishing, 2023) Wilson, M.O.; Huang, D.M.We develop a machine-learning method for coarse-graining condensed-phase molecular systems using anisotropic particles. The method extends currently available high-dimensional neural network potentials by addressing molecular anisotropy. We demonstrate the flexibility of the method by parametrizing single-site coarse-grained models of a rigid small molecule (benzene) and a semi-flexible organic semiconductor (sexithiophene), attaining structural accuracy close to the all-atom models for both molecules at a considerably lower computational expense. The machine-learning method of constructing the coarse-grained potential is shown to be straightforward and sufficiently robust to capture anisotropic interactions and many-body effects. The method is validated through its ability to reproduce the structural properties of the small molecule's liquid phase and the phase transitions of the semi-flexible molecule over a wide temperature range.Item Metadata only The bacterial cytochrome P450 (CYP) CYP125 enzymes can competitively oxidise sitosterol in the presence of cholesterol(Royal Society of Chemistry, 2023) Doherty, D.Z.; Ghith, A.; Ho, A.; De Voss, J.J.; Bell, S.G.Cholesterol catabolism is an important survival mechanism for the pathogenic Mycobacterium tuberculosis. Various other mycobacteria degrade not only cholesterol but plant sterols such as sitosterol and campesterol. In this work we demonstrate that the cytochrome P450 (CYP) CYP125 enzyme family is capable of sitosterol and campesterol side-chain oxidation and activation in these bacteria. We also show that the CYP142 and CYP124 cholesterol hydroxylating enzyme families are significantly less active for sitosterol hydroxylation compared to CYP125 enzymes.Item Open Access Spin-2 Kaluza-Klein scattering in a stabilized warped background(American Physical Society (APS), 2023) Chivukula, R.S.; Foren, D.; Mohan, K.A.; Sengupta, D.; Simmons, E.H.Scattering amplitudes involving massive spin-2 particles typically grow rapidly with energy. In this paper we demonstrate that the anomalous high-energy growth of the scattering amplitudes cancel for the massive spin-2 Kaluza-Klein modes arising from compactified five-dimensional gravity in a stabilized warped geometry. Generalizing previous work, we show that the two sum rules which enforce the cancellations between the contributions to the scattering amplitudes coming from the exchange of the (massive) radion and those from the exchange of the tower of Goldberger-Wise scalar states (admixtures of the original gravitational and scalar fields of the theory) still persist in the case of the warping which would be required to produce the hierarchy between the weak and Planck scales in a Randall-Sundrum model. We provide an analytic proof of one combination of these generalized scalar sum rules and show how the sum rule depends on the Einstein equations determining the background geometry and the mode-equations and normalization of the tower of physical scalar states. Finally, we provide a consistent and self-contained derivation of the equations governing the physical scalar modes, and we list, in appendixes, the full set of sum rules ensuring proper high-energy growth of all 2 → 2 massive spin-2 scattering amplitudes.Item Open Access The role of zircon in hydrothermal heavy REE mineralisation: The case for unconformity-related ore deposits of north-west Australia(Elsevier BV, 2023) Walsh, J.M.J.; Spandler, C.Zircon is hailed for its chemical and physical durability, but can undergo extensive chemical and structural modification due to radiation damage via the emission of alpha (α) particles, and subsequent low-temperature hydrothermal alteration. Here, we investigate Archean zircons from arkosic metasediments of the Browns Range Metamorphics (BRM) to evaluate their role in the formation of local unconformity-related heavy rare earth element (REE) ore deposits, within the Browns Range Dome, Western Australia. We determine that the heavy REE inventory of the BRM are primarily hosted in zircon, and that these zircons have a wide range of major element totals (77 to ~100 wt%, including low SiO2 and ZrO2 contents), and high and variable ‘nonformula’ components (U, Th, Y, REE, Nb, P, Al, Ca, Fe, Ti, F and OH− or H2O). Concentrations of Y + REE in some cases exceed 8 wt%. Extensive radiation damage (metamictisation) is confirmed by structural features including porous and amorphous domains, cavities, and voids. The lack of regional thermal events over an extended period likely prevented thermal annealing of these radiation-damaged zircons. Uptake of non-formula elements in metamict zircon, most likely during sedimentation in the late Archean, promoted further radiation damage, such that these grains remained highly susceptible to alteration by subsequent hydrothermal fluid circulation. We propose that the unconformity-related REE mineralisation was formed by saline fluids leaching Y + REE (and possibly P) from metamict zircon in the BRM, followed by ore mineral precipitation in fault zones near, and along the regional unconformity. More broadly, this model of ore formation may be relevant to other basin-hosted mineral systems, and could be used to guide exploration for unconformity-related REE deposits in Australia, and globally.Item Metadata only The use of computed tomography in the management of injury in tertiary emergency departments in Western Australia: Evidence of overtesting?(WILEY, 2022) Ha, N.T.; Abdullah, L.; Bulsara, M.; Celenza, A.; Doust, J.; Fatovich, D.; McRobbie, D.; Mountain, D.; O’Leary, P.; Slavotinek, J.; Wright, C.; Youens, D.; Moorin, R.Background: This study investigated trends in computed tomography (CT) utilization across different triage categories of injury presentations to tertiary emergency departments (EDs) and associations with diagnostic yield measured by injury severity, hospitalization and length of stay (LOS), and mortality. Methods: A total of 411,155 injury-related ED presentations extracted from linked records from Western Australia from 2004 to 2015 were included in the retrospective study. The use of CT scanning and diagnostic yield measured by rate of diagnosis with severe injury, hospitalizations and LOS, and mortality were captured annually for injury-related ED presentations. Multivariable regression models were used to calculate the annual adjusted rate of CT scanning for injury presentations and hospitalizations across triage categories, diagnosis with severe injury, LOS, and mortality. The significance of changes observed was compared among patients with CT imaging relative to those without CT. Results: While the number of ED presentations with injury increased by 65% from 2004 to 2015, the use of CT scanning in these presentations increased by 176%. The largest increase in CT use was among ED presentations triaged as semi-/nonurgent (+256%). Injury presentations with CT, compared to those without, had a higher rate of diagnosis with moderate/severe injury and hospitalization but no difference in LOS and mortality. The probability/rate observed in the outcomes of interest had a greater decrease over time in those with CT scanning compared with those without CT scanning across triage categories. Conclusions: The reduction in diagnostic yield in terms of injury severity and hospitalization found in our study might indicate a shift toward overtesting using CT in ED for injury or a higher use of CT to assist in the management of injuries. This helps health care policymakers consider whether the current increase in CT use meets the desired levels of quality and efficient care.Item Open Access Trend in CT utilisation and its impact on length of stay, readmission and hospital mortality in Western Australia tertiary hospitals: an analysis of linked administrative data 2003-2015(BMJ PUBLISHING GROUP, 2022) Ha, T.N.; Kamarova, S.; Youens, D.; Wright, C.; McRobbie, D.; Doust, J.; Slavotinek, J.; Bulsara, M.K.; Moorin, R.Objective: High use of CT scanning has raised concern due to the potential ionising radiation exposure. This study examined trends of CT during admission to tertiary hospitals and its associations with length of stay (LOS), readmission and mortality. Design Retrospective observational study from 2003 to 2015. Setting: West Australian linked administrative records at individual level. Participants: 2 375 787 episodes of tertiary hospital admission in adults aged 18+ years. Main outcome measures: LOS, 30-day readmissions and mortality stratified by CT use status (any, multiple (CTs to multiple areas during episode), and repeat (repeated CT to the same area)). Methods: Multivariable regression models were used to calculate adjusted rate of CT use status. The significance of changes since 2003 in the outcomes (LOS, 30-day readmission and mortality) was compared among patients with specific CT imaging status relative to those without. Results: Between 2003 and 2015, while the rate of CT increased 3.4% annually, the rate of repeat CTs significantly decreased −1.8% annually and multiple CT showed no change. Compared with 2003 while LOS had a greater decrease in those with any CT, 30- day readmissions had a greater increase among those with any CT, while the probability of mortality remained unchanged between the any CT/no CT groups. A similar result was observed in patients with multiple and repeat CT scanning, except for a significant increase in mortality in the recent years in the repeat CT group. Conclusion: The observed pattern of increase in CT utilisation is likely to be activity-based funding policydriven based on the discordance between LOS and readmissions. Meanwhile, the repeat CT reduction aligns with a more selective strategy of use based on clinical severity. Future research should incorporate in-hospital and out-of-hospital CT to better understand overall CT trends and potential shifts between settings over time.Item Metadata only A marine isotope stage 13 Acheulian sequence from the Amanzi Springs Area 2 Deep Sounding excavation, Eastern Cape, South Africa.(Elsevier, 2023) Caruana, M.V.; Wilson, C.G.; Arnold, L.J.; Blackwood, A.F.; Demuro, M.; Herries, A.I.R.Renewed research at Amanzi Springs has increased resolution on the timing and technology of the Acheulian industry in South Africa. The archeology from the Area 1 spring eye has recently been dated to MIS 11 (∼404-390 ka), and analyses revealed significant technological variability when compared to other southern African Acheulian assemblages. We expand on these results in presenting new luminescence dating and technological analyses of Acheulian stone tools from three artifact-bearing surfaces exposed within the White Sands unit of the Deep Sounding excavation in the Area 2 spring eye. The two lowest surfaces (Surfaces 3 and 2) are sealed within the White Sands and dated between ∼534 to 496 ka and ∼496 to 481 ka (MIS 13), respectively. Surface 1 represents materials deflated onto an erosional surface that cut the upper part of the White Sands (∼481 ka; late MIS 13), which occurred before the deposition of younger Cutting 5 sediments (<408-<290 ka; MIS 11-8). Archaeological comparisons reveal that the older Surface 3 and 2 assemblages are predominated by unifacial and bifacial core reduction and relatively thick, cobble-reduced large cutting tools. In contrast, the younger Surface 1 assemblage is characterized by discoidal core reduction and thinner large cutting tools, mostly made from flake blanks. Typological similarities between the older Area 2 White Sands and younger Area 1 (404-390 ka; MIS 11) assemblages further suggest long-term continuity in site function. We hypothesize Amanzi Springs represent a workshop locality that Acheulian hominins repeatedly visited to access unique floral, faunal, and raw material resources from at least ∼534 to 390 ka.Item Metadata only Manifestation of the coupling phase in microwave cavity magnonics(American Physical Society, 2023) Gardin, A.; Bourhill, J.; Vlaminck, V.; Person, C.; Fumeaux, C.; Castel, V.; Tettamanzi, G.C.The interaction between microwave photons and magnons is well understood and originates from the Zeeman coupling between spins and a magnetic field. Interestingly, the magnon-photon interaction is accompanied by a phase factor, which can usually be neglected. However, under the rotating wave approximation, if two magnon modes simultaneously couple with two cavity resonances, this phase cannot be ignored as it changes the physics of the system. We consider two such systems, each differing by the sign of one of the magnon-photon coupling strengths. This simple difference, originating from the various coupling phases in the system, is shown to preserve, or destroy, two potential applications of hybrid photon-magnon systems, namely dark-mode memories and cavity-mediated coupling. The observable consequences of the coupling phase in this system is akin to the manifestation of a discrete Pancharatnam-Berry phase, which may be useful for quantum information processing and the creation of nonreciprocal devices using proper cavity engineering.Item Metadata only Power Dependence of the Magnetic Field Effect on Triplet Fusion: A Quantitative Model(ACS Publications, 2023) Forecast, R.; Gholizadeh, E.M.; Prasad, S.K.K.; Blacket, S.; Tapping, P.C.; McCamey, D.R.; Tayebjee, M.J.Y.; Huang, D.M.; Cole, J.H.; Schmidt, T.W.Two strategies for improving solar energy efficiencies, triplet fusion and singlet fission, rely on the details of triplet−triplet interactions. In triplet fusion, there are several steps, each of which is a possible loss mechanism. In solution, the parameters describing triplet fusion collisions are difficult to inspect. Here we show that these parameters can be determined by examining the magnetic field dependence of triplet fusion upconversion. We show that there is a reduction of the magnetic field effect for perylene triplet fusion as the system moves from the quadratic to linear annihilation regimes with an increase in laser power. Our data are modeled with a small set of parameters that characterize the triplet fusion dynamics. These parameters are cross-validated with molecular dynamics simulations. This approach can be applied to both solution and solid state materials, providing a tool for screening potential annihilators for photon upconversion.