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Pulmonary squamous cell carcinoma is the second most common lung cancer subtype and has a low 5-year survival rate at 17.6%. Complete resection with negative margins can be curative, but a high number of patients suffer early postoperative recurrence due to inadequate disease clearance at the index operation. Intraoperative molecular imaging (IMI) with tumor-targeted optical contrast agents is effective in improving resection completeness for other tumor types, but there are no IMI tracers targeted to pulmonary squamous cell carcinoma. In this report, we describe the use of a novel prostate-specific membrane antigen (PSMA)-targeted near-infrared conjugate (OTL78) to identify pulmonary squamous cell carcinoma. We identified PSMA as a viable target by examining its expression in human lung tumor specimens from a surgical cohort. Ninety-four percent of tumors expressed PSMA in either the pulmonary squamous cells or the tumor neovasculature. Using in vitro and in vivo models, we found that OTL78 reliably localized pulmonary squamous cell carcinoma in a PSMA-dependent manner. Finally, we found that IMI with OTL78 markedly improved surgeons' ability to identify residual disease after surgery in a preclinical model. Ultimately, this novel optical tracer may aid surgical resection of pulmonary squamous cell carcinoma and potentially improve long-term outcomes.

We have investigated magnetoelectric coupling in the single-molecule magnet $\mathrm{Mn}_{4}\mathrm{Te}_{4}(\mathrm{P}\mathrm{Et}_{3})_{4}$ with tetrahedral spin frustration. Our density functional studies found that an electric dipole moment can emerge with various non-collinear spin orderings. The forms of spin-dependent dipole are determined and consistent with that in non-centrosymmetric magnets driven by the Dzyaloshinskii-Moriya interaction. Writing a parameterized spin Hamiltonian, after solving for eigenvalues and eigenstates we quantified the magnetoelectric coupling by calculating the thermal average of the electric and magnetic susceptibilities, which can be influenced by external magnetic and electric fields, respectively. The quadratic relations are expected to be observable in experiments., Comment: 8 pages, 6 figures

Intraoperative molecular imaging (IMI) with folate-targeted NIR tracers has been shown to improve lesion localization in more than 80% of lung adenocarcinomas. However, mucinous adenocarcinomas (MAs) and invasive mucinous adenocarcinomas (IMAs) of the lung, which are variants of adenocarcinoma, appear to have decreased fluorescence despite appropriate folate receptor expression on the tumor surface. We hypothesized that the etiology may be related to light excitation and emission through non-Newtonian fluid (mucin) produced by goblet and columnar cancer cells.Intraoperative data for 311 subjects were retrospectively reviewed from a prospectively collected 6-year database. For standardization, all patients underwent infusion of the same targeted molecular optical contrast agent (pafolacianine, folate receptor-targeted NIR fluorochrome) for lung cancer resections. Then, the ratio of the mean fluorescence intensity of the tumors and background tissues (TBR) was calculated. Tumors were examined for mucin, FRa, FRb, and immunofluorescent tracer uptake by a board-certified pathologist. The optical properties of mucin analyzed by imaging software were used to create in vitro gel models to explore the effects on NIR tracer fluorescence intensity.A large proportion (192, 62%) of the patients were female, with an average of 62.8 years and a 34-year mean pack smoking history. There were no severe (Clavien-Dindo gt; III) complications related to pafolacianine infusion. A total of 195 lesions in the study were adenocarcinomas, of which 19 (6.1%) were of the mucinous subtype. A total of 14/19 of the patients had a smoking history, and more than 74% of the IMA lesions were in the lower lobes. IMA lesions had a lower in situ TBR than nonmucinous adenocarcinomas (2.64 SD 0.23) vs (3.45 SD 0.11), respectively (p lt; 0.05). Only 9/19 (47%) were localized in situ. Tumor bisection and removal of mucin from IMAs significantly increased pafolacianine fluorescence, with resultant TBR not being significantly different from the control group (4.67 vs 4.89) (p = 0.19). Of the 16 lesions that underwent FR expression analysis, 15/16 had FR presence on cancer cells or tumor-associated macrophages in the tumor microenvironment. There was no statistically significant difference in fluorescence intensity during immunofluorescence analysis (4.99 vs 5.08) (p = 0.16). Physical removal of mucin from IMAs improved the TBR from 3.11 to 4.67 (p lt; 0.05). In vitro analysis of the impact of synthetic non-Newtonian fluid (agarose 0.5%) on NIR tracer fluorescence showed a decrease in MFI by a factor of 0.25 regardless of the concentration for each 5 mm thickness of mucin.The mucinous subtype of lung adenocarcinomas presents a unique challenge in pafolacianine-targeted IMI-guided resections. The presence of non-Newtonian fluids presents a physical barrier that dampens the excitation of the tracer and fluorescence emission detected by the camera. Knowledge of this phenomenon can allow the surgeon to critically analyze lesion fluorescence parameters during IMI-guided lung cancer resections.

Background The diagnostic yield of biopsies of solitary pulmonary nodules (SPNs) is low, particularly in sub-solid lesions. We developed a method (NIR-nCLE) to achieve cellular level cancer detection during biopsy by integrating (i) near-infrared (NIR) imaging using a cancer-targeted tracer (pafolacianine), and (ii) a flexible NIR confocal laser endomicroscopy (CLE) system that can fit within a biopsy needle. Our goal was to assess the diagnostic accuracy of NIR-nCLE ex vivo in SPNs. Methods Twenty patients with SPNs were preoperatively infused with pafolacianine. Following resection, specimens were inspected to identify the lesion of interest. NIR-nCLE imaging followed by tissue biopsy was performed within the lesion and in normal lung tissue. All imaging sequences (n = 115) were scored by 5 blinded raters on the presence of fluorescent cancer cells and compared to diagnoses by a thoracic pathologist. Results Most lesions (n = 15, 71%) were adenocarcinoma-spectrum malignancies, including 7 ground glass opacities (33%). Mean fluorescence intensity (MFI) by NIR-nCLE for tumor biopsy was 20.6 arbitrary units (A.U.) and mean MFI for normal lung was 6.4 A.U. (p κ = 0.95). Conclusions NIR-nCLE allows sensitive and specific detection of cancer cells in SPNs. This technology has far-reaching implications for diagnostic needle biopsies and intraprocedural decision-making.

Pulsed NMR techniques have been used to study the dynamics of $$^3\hbox {He}$$ confined to the interior of the hexagonal nanochannels of MCM-41 for which the walls were coated with a monolayer of $$^4\hbox {He}$$ as determined by isotherm measurements. The $$^3\hbox {He}$$ was added afterward to form a 1D $$^3\hbox {He}$$ line density of about 0.1 $$\hbox {A}^{-1}$$ , corresponding to a Fermi temperature of $$T_{\mathrm{F}} \sim$$ 120 mK. A distinct and appreciable departure from the Curie law was observed for the nuclear spin magnetization below 0.5 K. The temperature dependence of the nuclear spin–lattice relaxation times, $$T_1$$ , for temperatures $$0.05

MCM-41 is a unique mesoporous material with cylindrical-like pores that provide an ideal platform to study 1D properties of adsorbed atoms (Boninsegni and Moroni in J Low Temp Phys 118(1):1, 2000). In this research, we use pulsed NMR to measure the nuclear spin-lattice relaxation times ( $$T_1$$ ) of $$^3$$ He adsorbed onto $$^4$$ He-preplated MCM-41 over a wide range of temperatures for a line density that would lead to a Fermi temperature of 200 mK. The temperature dependence of the nuclear spin-lattice relaxation time for $$ 0.025

Objective: Cancer-associated fibroblasts (CAFs) are a key component of the tumor microenvironment and affect neoplastic progression by stromal remodeling, paracrine signaling, potentiating cancer cell proliferation, and immune system evasion. As such, they are a potential target for optimizing therapeutic and diagnostic strategies. The purpose of our study was to evaluate if Fibroblast Activation Protein (FAP) can be a suitable target for molecular imaging guided cancer localization during surgery because FAP is overwhelmingly expressed by CAFs. Methods: Patient derived lung adenocarcinoma FAP+/alpha SMA+ myofibroblasts (CAFs) were isolated by flow cytometry and cultured according to institutional best practices. Normal fibroblasts from 3T3 cell line were used as negative control whereas normal lung fibroblasts transfected with human FAP cDNA were used as positive control. Cell expression of FAP was compared using SDS Page analysis and flow cytometry. FAP ligand coupled to NIR S0456 fluorochrome (FAP-S0456) was then evaluated with in-vitro dose escalation, cell-toxicity study, fluorescence parameters, and immunofluorescence microscopy. Results: Patient derived lung cancer (LC) CAFs had lower FAP-S0456 dye binding expression compared to transfected fibroblasts (TF), while normal fibroblasts (FAP-, aSMA-) had no FAP-S0456 dye binding detected on FACS direct antibody analysis (MFI 1033 vs 244, p Conclusion: FAP transmembrane receptor is highly expressed in cancer associated fibroblasts and can serve as a potential target for FAP ligand conjugated near-infrared tracers. This study demonstrates proof of principle of utilizing FAP-S0456 in CAF in-vitro models and paves a path for pre-clinical diagnostic and therapeutic validation for surgical applications. Citation Format: Feredun Azari, Gregory Kennedy, Ashley Chang, Bilal Nadeem, Neil Sullivan, Emanuel Encarnado, Steven Albelda, Evgeniy Eruslanov, Sunil Singhal. Fibroblast activation protein transmembrane receptor targeted near-infrared fluorochrome specifically identifies patient derived lung cancer associated fibroblasts in pre-clinical models [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2022; 2022 Apr 8-13. Philadelphia (PA): AACR; Cancer Res 2022;82(12_Suppl):Abstract nr 4142.

We use density functional theory to study the structural, magnetic, and electronic structures of the organometallic quantum magnet ${\mathrm{NiCl}}_{2}\text{\ensuremath{-}}4\mathrm{SC}{({\mathrm{NH}}_{2})}_{2}$ (DTN). Recent work has demonstrated the quasi one-dimensional nature of the molecular crystal and studied its quantum phase transitions at low temperatures. The system includes a magnetoelectric (ME) coupling and, when doped with Br, the presence of an exotic Bose-glass state. Using the generalized gradient approximation with inclusion of a van der Waals term to account for weak intermolecular forces and by introducing a Hubbard $U$ term to the total energy, we systematically show that our calculations reproduce the magnetic anisotropy, the intermolecular exchange coupling strength, and the magnetoelectric effect in DTN, which have been observed in previous experiments. Further analysis of the electronic structure gives insight into the underlying magnetic interactions, including what mechanisms may be causing the ME effect. Using this computationally efficient model, we predict what effect applying an electric field might have on the magnetic properties of this quantum magnet.

This paper reports on a cavity haloscope search for dark matter axions in the galactic halo in the mass range $2.81$-$3.31$ ${\mu}eV$. This search excludes the full range of axion-photon coupling values predicted in benchmark models of the invisible axion that solve the strong CP problem of quantum chromodynamics, and marks the first time a haloscope search has been able to search for axions at mode crossings using an alternate cavity configuration. Unprecedented sensitivity in this higher mass range is achieved by deploying an ultra low-noise Josephson parametric amplifier as the first stage signal amplifier.

Searching for axion dark matter, the ADMX collaboration acquired data from January to October 2018, over the mass range 2.81--3.31 $\mu$eV, corresponding to the frequency range 680--790 MHz. Using an axion haloscope consisting of a microwave cavity in a strong magnetic field, the ADMX experiment excluded Dine-Fischler-Srednicki-Zhitnisky (DFSZ) axions at 100% dark matter density over this entire frequency range, except for a few gaps due to mode crossings. This paper explains the full ADMX analysis for Run 1B, motivating analysis choices informed by details specific to this run., Comment: 17 pages, 17 figures

A report on the progress on the high resolution data analysis of the ADMX experimental results is presented. In this paper, tools are developed and tested on a blind injection mimicking a Maxwellian like signal in the frequency domain. This blind injection will be used as a test bed which can be later implemented on all the high resolution data. The high resolution data is stored in the Fermilab server. In this analysis a PostgreSQL query was made to ensure the blind injection is in the middle of the frequency spectrum and 19 such files were found. The time series data is read using a c++ program. An apodization function is applied on the time series data and zero filled to reduce the frequency spacing in order to achieve a better interpolation. A FFTW header is used to compute the Fourier transform of the time series data. A Savitzky–Golay filter is applied on the unnormalized power which then can be used to remove the spectral shape. Each frequency spectrum has a bandwidth of 50 kHz.

An axion is a particle that could resolve some issues with strong interaction CP symmetry and dark matter. A tunable microwave cavity permeated by a strong external magnetic field can be used to detect axions. The Axion Dark Matter eXperiment (ADMX) has developed a four-cavity array design to explore the axion mass range of 5–9 μeV. Tuning of each cavity frequency is done primarily by a coarse tuning rod, with a fine tuning rod used to lock frequencies together. Aluminum prototypes at 1:3 scale have been built and tested. At 300 K, the TM010 frequency varied from 4.4 to 6.4 GHz and crossed three TE modes. Electroplating pure aluminum on the cavity improved the Q factor by 27%. Preliminary results from 4.2 K test showed a 2% reduction of resonant frequency and an improvement in Q by a factor of 2.7 compared to the 300 K values.

The anomalous frequency dependence observed for the magneto-electric effect in the Bose glass state of dichloro-tetrakis-thoiurea-nickel doped with bromine is analyzed in terms of the hierarchical droplet model of spin glasses. In this model low energy barriers must be overcome before accessing higher energy states leading to scaling laws for the spin correlation functions and an associated frequency dependence for transition rates.

We report the design and operation of a new device for measuring the magneto-electric effects, dielectric susceptibility, and electrical resistance of materials at very low temperatures (below 10 mK). The unique feature of the device is the immersion of the sample in liquid $$^{3}\hbox {He}$$ which is cooled with a large ( $$25\hbox { m}^{2})$$ surface area sintered silver heat exchanger connected to the nuclear stage of a demagnetization refrigerator. In addition to a DC applied magnetic field (up to 16 T), an AC magnetic field is provided by a Helmholtz coil located outside the sample. With this design the magnetic field-dependent electric susceptibilities, and the DC and AC resistance can be measured simultaneously. The details and performance of the device are discussed, and measurements on interesting new materials such as quantum organic magnets are presented.

The $a\phantom{\rule{0}{0ex}}x\phantom{\rule{0}{0ex}}i\phantom{\rule{0}{0ex}}o\phantom{\rule{0}{0ex}}n$ particle is one of the most promising candidates for the constitution of cold dark matter. As researchers of axion dark matter continue to scan for higher masses, the detectors become more sensitive to anomalous effects, which could confound the search. This analysis examines the effects of breaking translational invariance within cylindrical microwave cavities similar to those typically used in haloscope detectors. Breaking translational invariance causes avoided mode crossings, a discovery that enables experiments to mitigate these effects in the detectors used in the axion quest.

The $\mu$eV axion is a well-motivated extension to the standard model. The Axion Dark Matter eXperiment (ADMX) collaboration seeks to discover this particle by looking for the resonant conversion of dark-matter axions to microwave photons in a strong magnetic field. In this Letter, we report results from a pathfinder experiment, the ADMX "Sidecar," which is designed to pave the way for future, higher mass, searches. This testbed experiment lives inside of and operates in tandem with the main ADMX experiment. The Sidecar experiment excludes masses in three widely spaced frequency ranges (4202-4249, 5086-5799, and 7173-7203 MHz). In addition, Sidecar demonstrates the successful use of a piezoelectric actuator for cavity tuning. Finally, this publication is the first to report data measured using both the TM$_{010}$ and TM$_{020}$ modes., Comment: 7 Pages, 4 figures

We discuss the analysis of the experimental values of the nuclear spin–lattice and spin–spin relaxation times for the tunneling of $$^3$$ He as isotopic impurities in solid $$^4$$ He. These two relaxation times cannot be described quantitatively using a unique correlation time although it is often presented as such in the literature. In this paper, we discuss how to distinguish the high-frequency portion of the spectral densities that determine the spin–lattice relaxation rates from the low-frequency components which determine the spin–spin relaxation rates.

We review the properties of simple diatomic molecular glasses as explored by nuclear magnetic resonance techniques and measurements of the dielectric susceptibility. We focus on the behavior of classical molecular rotors formed by solid N2–Ar mixtures and discuss the time dependent behavior in terms of replica symmetry breaking theories.

The motion of hydrogen deuteride molecules adsorbed on MCM-41 at monolayer coverages has been explored using NMR techniques. The nuclear spin-spin and nuclear spin-lattice relaxation times show an abrupt change at 8.8 K, consistent with the formation of small clusters below that temperature. The molecular tunneling times deduced from the NMR measurements are consistent with the values determined by neutron scattering [Coulomb et al., Micro Meso Matls 101,270 (2007)].

This Letter reports results from a haloscope search for dark matter axions with masses between 2.66 and 2.81 $\mu$eV. The search excludes the range of axion-photon couplings predicted by plausible models of the invisible axion. This unprecedented sensitivity is achieved by operating a large-volume haloscope at sub-kelvin temperatures, thereby reducing thermal noise as well as the excess noise from the ultra-low-noise SQUID amplifier used for the signal power readout. Ongoing searches will provide nearly definitive tests of the invisible axion model over a wide range of axion masses., Comment: 5 pages, 4 figures

Axion haloscope detectors use microwave cavities permeated by a magnetic field to resonate photons that are converted from axions due to the inverse Primakoff effect. The sensitivity of a detector is proportional to the form factor of the cavity’s search mode. Transverse symmetry breaking is used to tune the search modes for scanning across a range of axion masses. However, numerical analysis shows transverse and longitudinal symmetry breaking reduce the sensitivity of the search mode. Simulations also show longitudinal symmetry breaking leads to other undesired consequences like mode mixing and mode crowding. The results complicate axion dark matter searches and further reduce the search capabilities of detectors. The findings of a numerical analysis of symmetry breaking in haloscope microwave cavities are presented.

Axions are a promising cold dark matter candidate. Haloscopes, which use the conversion of axions to photons in the presence of a magnetic field to detect axions, are the basis of microwave cavity searches such as ADMX. To search for lighter, low frequency axions in the unexplored < 2 × 10−7 eV (50 MHz) range a tunable LC circuit has been proposed. Progress in the development of such an LC circuit based search is presented here. This will include preliminary results from prototypes using electrical tuning, superconducting loop antenna, and aluminum shielding.

A Pound reflection locking method is used to tune to a desired frequency high-Q microwave resonant cavities to be used for axion detection. A phase-modulated RF signal is fed to the cavity and the reflected RF signal is detected with a zero-bias Schottky diode detector. The detected signal is analyzed using a lock-in amplifier synchronized to the phase modulation frequency. The lock-in output is integrated and amplified to provide the feedback signal to a servomechanism to lock the resonant cavity to the desired frequency.

We present a new simplified derivation of the effect of lattice relaxation that accompanies the quantum tunneling of 3He impurities in solid 4He on the nuclear spin-lattice relaxation of the 3He impurities for very low impurity concentrations. As a result of the larger zero point motion of the 3He impurity compared to the 4He atoms, a significant lattice distortion accompanies the impurity as it moves through the lattice and the dynamics of the impurity depends on both the interaction energy between two 3He atoms and on the relaxation of the lattice for the tunneling impurity. Using a phenomenological model for the lattice relaxation we compare the nuclear spin-lattice relaxation rates observed at low temperatures with the dependence on temperature expected for a 4He lattice relaxation comparable to that observed by Beamish et al. (Phys. Rev. Lett. 96:195304, 2006).

A rapid high-pressure liquid chromatography (HPLC) tandem mass spectrometry (TQD) method for the determination of artemisinin, 9-epi-artemisinin, artemisitene, dihydroartemisinic acid, artemisinic acid and arteannuin B in Artemisia annua extracts is described. Detection and quantification of 9-epi-artemisinin in crude extracts are reported for the first time. In this method all six metabolites are resolved and eluted within 6 min with minimal sample preparation. A recovery of between 96.25% and 103.59% was obtained for all metabolites analysed and the standard curves were linear (r(2)0.99) over the concentration range of 0.15-10 μg mL(-1) for artemisinin, 9-epi-artemisinin, artemisitene and arteannuin B, and the range of 3.75-120 μg mL(-1) for dihydroartemisinic acid and artemisinic acid. All validation indices were satisfactory, showing the method to be robust, quick, sensitive and adequate for a range of applications including high throughput (HTP) analysis.

Measurements of nuclear spin relaxation times over a wide temperature range have been used to determine the interaction energies and molecular dynamics of light molecular gases trapped in the cages of microporous structures. The experiments are designed so that, in the cases explored, the local excitations and the corresponding heat capacities determine the observed nuclear spin-lattice relaxation times. The results indicate well-defined excitation energies for low densities of methane and hydrogen deuteride in zeolite structures. The values obtained for methane are consistent with Monte Carlo calculations of A.V. Kumar et al. The results also confirm the high mobility and diffusivity of hydrogen deuteride in zeolite structures at low temperatures as observed by neutron scattering.

Non-virialized dark-matter axions may be present in the Milky Way halo in the form of low-velocity-dispersion flows. The Axion Dark Matter eXperiment performed a search for the conversion of these axions into microwave photons using a resonant cavity immersed in a strong, static magnetic field. The spread of photon energy in these measurements was measured at spectral resolutions of the order of 1 Hz and below. If the energy variation were this small, the frequency modulation of any real axion signal due to the orbital and rotational motion of the Earth would become non-negligible. Conservative estimates of the expected signal modulation were made and used as a guide for the search procedure. The photon frequencies covered by this search are 812$-$852 and 858$-$892 MHz, which correspond to an axion mass of 3.36$-$3.52 and 3.55$-$3.69 {\mu}eV. No axion signal was found, and limits were placed on the maximum local density of non-virialized axions of these masses., Comment: 12 pages, 12 figures

In an effort to extend the usefulness of microwave cavity detectors to higher axion masses, above ~8 $\mu$eV (~2 GHz), a numerical trade study of cavities was conducted to investigate the merit of using variable periodic post arrays and regulating vane designs for higher-frequency searches. The results show that both designs could be used to develop resonant cavities for high-mass axion searches. Multiple configurations of both methods obtained the scanning sensitivity equivalent to approximately 4 coherently coupled cavities with a single tuning rod., Comment: 10 pages, 7 figures, 1 table

We review the results of nuclear magnetic resonance studies of the molecular dynamics of the quantum gases HD and CH4 adsorbed in the cages of microporous structures. Measurements of the variation of the nuclear spin-lattice and nuclear spin-spin relaxation times with temperature provide detailed information about the translational and rotational dynamics of the adsorbed molecules over a wide temperature range.

The low-temperature states of bosonic fluids exhibit fundamental quantum effects at the macroscopic scale: the best-known examples are Bose-Einstein condensation (BEC) and superfluidity, which have been tested experimentally in a variety of different systems. When bosons are interacting, disorder can destroy condensation leading to a so-called Bose glass. This phase has been very elusive to experiments due to the absence of any broken symmetry and of a finite energy gap in the spectrum. Here we report the observation of a Bose glass of field-induced magnetic quasiparticles in a doped quantum magnet (Br-doped dichloro-tetrakis-thiourea-Nickel, DTN). The physics of DTN in a magnetic field is equivalent to that of a lattice gas of bosons in the grand-canonical ensemble; Br-doping introduces disorder in the hoppings and interaction strengths, leading to localization of the bosons into a Bose glass down to zero field, where it acquires the nature of an incompressible Mott glass. The transition from the Bose glass (corresponding to a gapless spin liquid) to the BEC (corresponding to a magnetically ordered phase) is marked by a novel, universal exponent governing the scaling on the critical temperature with the applied field, in excellent agreement with theoretical predictions. Our study represents the first, quantitative account of the universal features of disordered bosons in the grand-canonical ensemble., Comment: 13+6 pages, 5+6 figures; v2: Fig. 5 updated

A careful measurement of the dielectric constant of solid 4He was made to search for signatures associated with the reported onset of nonclassical rotational inertia and shear modulus stiffening. The samples studied include zero-pressure liquid, solid-liquid mixtures on the melting-curve and solid helium. It was found that the dielectric constant of solid 4He decreases smoothly with temperature below 300 mK, showing no measurable anomalies down to 50 mK. The new measurements do not show the anomalous upturn effect that was reported in our previous measurements.

The Mott insulator in correlated electron systems arises from classical Coulomb repulsion between carriers to provide a powerful force for electron localization. Turning such an insulator into a metal, the so-called Mott transition, is commonly achieved by "bandwidth" control or "band filling." However, both mechanisms deviate from the original concept of Mott, which attributes such a transition to the screening of Coulomb potential and associated lattice contraction. Here, we report a pressure-induced isostructural Mott transition in cubic perovskite PbCrO3. At the transition pressure of ∼3 GPa, PbCrO3 exhibits significant collapse in both lattice volume and Coulomb potential. Concurrent with the collapse, it transforms from a hybrid multiferroic insulator to a metal. For the first time to our knowledge, these findings validate the scenario conceived by Mott. Close to the Mott criticality at ∼300 K, fluctuations of the lattice and charge give rise to elastic anomalies and Laudau critical behaviors resembling the classic liquid-gas transition. The anomalously large lattice volume and Coulomb potential in the low-pressure insulating phase are largely associated with the ferroelectric distortion, which is substantially suppressed at high pressures, leading to the first-order phase transition without symmetry breaking.

Protic ionic liquids (PILs) have been suggested as “greener” alternatives to conventional solvents in various industrial applications. In order to assess their suitability for such purposes, a thorough evaluation of their toxicity, mutagenicity, carcinogenicity and environmental impact is crucial. Whilst some studies have been published concerning the biodegradability and toxicity towards microorganisms of a limited number of PILs, no data concerning the mutagenicity of any PIL exist within the literature. As part of our ongoing studies into the toxicity and environmental impact of PILs, we quantify herein the mutagenic potential of a range of PILs through the mini Ames test. In total, 16 PILs and two precursor amines were assessed based on the Ames test, using Salmonella typhimurium strains TA98 and TA100. The 16 PILs used in this study included both carboxylate and chloride anions, as well as secondary and tertiary ammonium cations. Our results show that out of the 16 PILs, 15 gave negative results to the mini Ames test, concluding that they are unlikely to be either mutagenic or carcinogenic. The PIL N,N-Dimethylethanolammonium Octanoate ([DMEtA][Oct]) was toxic to both test strains, and its mutagenic potential could not be assessed by the mini Ames test. The two precursor amines, diethanolamine and N,N-dimethylethanolamine, gave negative results to the mini Ames tests despite the suggestion from other mutagenicity tests of diethanolamine’s suggested carcinogenicity. 15 PILs have been deemed likely to be neither mutagenic nor carcinogenic in accordance with the mini Ames test. We find that these results compare well to the relevant carboxylic acids and amines from the literature, suggesting that PILs exist as well solvated ions in these test conditions, similar to those of their precursors in the same test. From this, we caution the use of secondary ammonium cations in PILs, as certain secondary amines have been suggested to be potentially carcinogenic, despite their results from the mini Ames test.

Careful measurements of the dielectric properties of solid 4He have been carried out down to 35 mK, considerably lower than the temperature range of previous studies. The sample was prepared from high purity gas with 3He concentrations of the order of 200 ppb and were formed by the blocked capillary method. The molar volume of the sample was 20.30 cm3. The dielectric constant of the samples was found to be independent of temperature down to 120 mK before showing a continuous increase with decreasing temperature and saturating below 50 mK. The total increase in e is 2 parts in 10−5. The temperature dependence of e mimics the increase in the resonant frequency found in the torsional oscillator studies and also the increase found in the shear modulus measurements.

We have performed measurements of the temperature dependence of the nuclear spin-lattice relaxation times (T 1) for a wide range of 3He concentrations for dilute mixtures of 3He in solid 4He. The temperatures for phase separation are determined for 3He concentrations 500

There is considerable interest in the use of mesoporous structures (e.g. zeolites and metal organic frameworks) for hydrogen storage but little is known about the molecular interactions and the dynamics of molecules inside the cages of these structures. In order to determine these properties we have measured the nuclear magnetic spin-lattice and spin-spin relaxation times of HD molecules trapped in the α-cages of zeolite 13X for a wide temperature range 1.6 12 K, corresponding to the onset of intercage diffusion.

We report measurements of the nuclear spin-spin and spin-lattice relaxation times for 3He adsorbed on MCM-41 for temperatures 0.08 < T < 1.2 K. Deviations from Curie behavior are observed at low temperatures. The relaxation times exhibit a two-component behavior representing the differing dynamics of the mobile quasi-free molecules in the center of the tubes compared to the adsorbed layer on the walls. The amplitudes of the two components provide an accurate measure of the number of fluid-like molecules traveling in the center of the nanotubes.

We review the results of a wide range of nuclear magnetic resonance (NMR)measurements of the local order parameters and the molecular dynamics of solid ortho-para hydrogen mixtures and solid nitrogen-argon mixtures that form novel molecular orientational glass states at low temperatures. From the NMR measurements, the distribution of the order parameters can be deduced and, in terms of simple models, used to analyze the thermodynamic measurements of the heat capacities of these systems. In addition, studies of the dielectric susceptibilities of the nitrogen-argon mixtures are reviewed in terms of replica symmetry breaking analogous to that observed for spin glass states. It is shown that this wide set of experimental results is consistent with orientation or quadrupolar glass ordering of the orientational degrees of freedom.

We report the design and operation of a device for ac magnetic susceptibility measurements that can operate down to 1 mK. The device, a modification of the standard mutual inductance bridge, is designed with detailed consideration of the thermalization and optimization of each element. First, in order to reduce local heating, the primary coil is made with superconducting wire. Second, a low-temperature transformer which is thermally anchored to the mixing chamber of a dilution refrigerator, is used to match the output of the secondary coil to a high-sensitivity bridge detector. The careful thermal anchoring of the secondary coil and the matching transformer is required to reduce the overall noise temperature and maximize sensitivity. The sample is immersed in liquid 3He to minimize the Kapitza thermal resistance. The magnetic susceptibility of several magnetic compounds, such as the well-known spin gap compound NiCl2-4SC(NH2)2 and other powdered samples, have been successfully measured to temperatures well below 10 mK.

We report the results of NMR studies of methane trapped in zeolite at low temperatures. Samples were prepared to contain 1.0±0.2 molecules per α-sodalite cage of zeolite-13X. The NMR spin-spin and spin-lattice relaxation times were measured for 4