Lights, Facts, and Goals: A Novel Framework to Enhance Community Health Messaging Campaign Design, Implementation, and Assessment.

The spread of health misinformation has made the task of health communicators more difficult. However, the success of health messaging hinges not only on meaningful message content but also on the credibility of who is delivering the message. "Trusted messengers," like local leaders and community-based organizations, have a greater ability to influence improvements in community health, due to their shared cultural experience with their communities. Health communication agencies should empower trusted messengers with the tools they need to succeed in health communication. One tool critical for their success is a succinct health messaging framework to plan and implement health messaging. Marketing has "See, Think, Do"-a simple, practical framework used to influence consumer purchases. As a more trustworthy corollary, we propose the "Lights, Facts, and Goals" framework, a concise, authentic, and transparent method for planning, implementing, and assessing health messaging campaigns that influence health improvements. "Lights" refers to different methods of reaching communities like trusted messengers, advertisements, and text messages. "Facts" refers to key sourced scientific information relevant to a specific aspect of community health. "Goals" refers to actions community members can take to improve their health in connection with the communicated health facts. This article describes how the "Lights, Facts, and Goals" framework both simplifies the creation and communication of scientifically sound health messaging and strengthens the partnership between health agencies and trusted messengers in the community. Through "Lights, Facts, and Goals," community-based organizations, community leaders, and their partners will be more effective at improving community health through messaging.

Unconventional Magnetic and Resistive Hysteresis in an Iodine-Bonded Molecular Conductor.

Simultaneous manipulation of both spin and charge is a crucial issue in magnetic conductors. We report on a strong correlation between magnetism and conductivity in the iodine-bonded molecular conductor (DIETSe)2 FeBr2 Cl2 [DIETSe=diiodo(ethylenedithio)tetraselenafulvalene], which is the first molecular conductor showing a large hysteresis in both magnetic moment and magnetoresistance associated with a spin-flop transition. Utilizing a mixed-anion approach and iodine bonding interactions, we tailored a molecular conductor with random exchange interactions exhibiting unforeseen physical properties.

Photomagnetic response in highly conductive iron(II) spin-crossover complexes with TCNQ radicals.

Co-crystallization of a cationic Fe(II) complex with a partially charged TCNQ(.δ-) (7,7',8,8'-tetracyanoquinodimethane) radical anion has afforded molecular materials that behave as narrow band-gap semiconductors, [Fe(tpma)(xbim)](X)(TCNQ)(1.5)⋅DMF (X=ClO4(-) or BF4(-); tpma=tris(2-pyridylmethyl)amine, xbim=1,1'-(α,α'-o-xylyl)-2,2'-bisimidazole). Remarkably, these complexes also exhibit temperature-and light-driven spin crossover at the Fe(II) center, and are thus the first structurally defined magnetically bistable semiconductors assembled with the TCNQ(.δ-) radical anion. Transport measurements reveal the conductivity of 0.2 S cm(-1) at 300 K, with the low activation energy of 0.11 eV.

Carbon nanotubes on a spider silk scaffold.

Understanding the compatibility between spider silk and conducting materials is essential to advance the use of spider silk in electronic applications. Spider silk is tough, but becomes soft when exposed to water. Here we report a strong affinity of amine-functionalised multi-walled carbon nanotubes for spider silk, with coating assisted by a water and mechanical shear method. The nanotubes adhere uniformly and bond to the silk fibre surface to produce tough, custom-shaped, flexible and electrically conducting fibres after drying and contraction. The conductivity of coated silk fibres is reversibly sensitive to strain and humidity, leading to proof-of-concept sensor and actuator demonstrations.

Variable range hopping in single-wall carbon nanotube thin films: a processing-structure-property relationship study.

By varying the ultrasonication and ultracentrifugation conditions, single-walled carbon nanotube (SWCNT) dispersions with a broad range of SWCNT length and diameter (L = 342-3330 nm; d = 0.5-12 nm) were prepared and characterized by a preparative ultracentrifuge method (PUM) and dynamic light scattering (DLS) technique. The well-characterized dispersions were then fabricated into SWCNT thin films by spray coating. Combined optical, spectroscopic, and temperature-dependent electrical measurements were performed to study the effect of SWCNT structures on the charge transport behavior of SWCNT thin films. Regardless of SWCNT size in the dispersion and the thin film thickness, the three-dimensional variable range hopping (3D VRH) conduction model was found to be appropriate in explaining the temperature-dependent sheet resistance results for all SWCNT thin films prepared in this study. More importantly, with the SWCNT structural information determined by the PUM method, we were able to identify a strong correlation between the length of SWCNTs and the 3D VRH parameter T0, the Mott characteristic temperature. When the SWCNT length is less than ∼700 nm, the T0 of SWCNT thin films shows a drastic increase, but when the length is greater than ~700 nm, T0 is only weakly dependent on the SWCNT length. Under the framework of traditional VRH, we further conclude that the electron localization length of SWCNT thin films shows a similar dependence on the SWCNT length.

Interlayer charge disproportionation in the layered organic superconductor κ(H)-(DMEDO-TSeF)2[Au(CN)4](THF) with polar dielectric insulating layers.

We report the molecular dipole effect on conduction electrons in the title superconductor. The angular-dependent magnetoresistance has a peak for fields nearly parallel to the conducting layer, and the peak width scales as the field component perpendicular to the layer, indicating incoherent interlayer transport. However, two closed Fermi surfaces are observed in quantum oscillation. Accordingly, crystallographically independent layers have different charge densities in a bulk single crystal. The electric dipole of tetrahydrofuran gives rise to interlayer charge disproportionation.

Physical characterization of functionalized spider silk: electronic and sensing properties.

This work explores functional, fundamental and applied aspects of naturally harvested spider silk fibers. Natural silk is a protein polymer where different amino acids control the physical properties of fibroin bundles, producing, for example, combinations of ß-sheet (crystalline) and amorphous (helical) structural regions. This complexity presents opportunities for functional modification to obtain new types of material properties. Electrical conductivity is the starting point of this investigation, where the insulating nature of neat silk under ambient conditions is described first. Modification of the conductivity by humidity, exposure to polar solvents, iodine doping, pyrolization and deposition of a thin metallic film are explored next. The conductivity increases exponentially with relative humidity and/or solvent, whereas only an incremental increase occurs after iodine doping. In contrast, iodine doping, optimal at 70 °C, has a strong effect on the morphology of silk bundles (increasing their size), on the process of pyrolization (suppressing mass loss rates) and on the resulting carbonized fiber structure (that becomes more robust against bending and strain). The effects of iodine doping and other functional parameters (vacuum and thin film coating) motivated an investigation with magic angle spinning nuclear magnetic resonance (MAS-NMR) to monitor doping-induced changes in the amino acid-protein backbone signature. MAS-NMR revealed a moderate effect of iodine on the helical and ß-sheet structures, and a lesser effect of gold sputtering. The effects of iodine doping were further probed by Fourier transform infrared (FTIR) spectroscopy, revealing a partial transformation of ß-sheet-to-amorphous constituency. A model is proposed, based on the findings from the MAS-NMR and FTIR, which involves iodine-induced changes in the silk fibroin bundle environment that can account for the altered physical properties. Finally, proof-of-concept applications of functionalized spider silk are presented for thermoelectric (Seebeck) effects and incandescence in iodine-doped pyrolized silk fibers, and metallic conductivity and flexibility of micron-sized gold-sputtered silk fibers. In the latter case, we demonstrate the application of gold-sputtered neat spider silk to make four-terminal, flexible, ohmic contacts to organic superconductor samples.

Organic crystals: properties, devices, functionalization and bridges to bio-molecules.

The purpose of this critical review is twofold: first, to review organic "small molecule" crystalline materials in terms of structure and function; and second, to consider if and how such materials might eventually enter the realm of device applicability. This area, one of the most interdisciplinary fields of research in contemporary materials science, embraces chemistry, physics, engineering, biology, theory and computation. The review therefore attempts to treat a relatively large number of examples including fundamental physical and electronic structure, single component and charge transfer complexes, physical properties of single crystalline materials, thin film and single crystal electronic and photonic devices, functional materials, and bio-inspired structures. The point of view is that of an experimental physicist, and in this context, challenges and possible routes to further advances in the development and utilization of organic small molecule materials are discussed for both fundamental and applied purposes (153 references).

Electromagnetic interference shielding properties of carbon nanotube buckypaper composites.

Preformed carbon nanotube thin films (10-20 microm), or buckypapers (BPs), consist of dense and entangled nanotube networks, which demonstrate high electrical conductivity and provide potential lightweight electromagnetic interference (EMI) solutions for composite structures. Nanocomposite laminates consisting of various proportions of single-walled and multi-walled carbon nanotubes, having different conductivity, and with different stacking structures, were studied. Single-layer BP composites showed shielding effectiveness (SE) of 20-60 dB, depending on the BP conductivity within a 2-18 GHz frequency range. The effects on EMI SE performance of composite laminate structures made with BPs of different conductivity values and epoxy or polyethylene insulating layer stacking sequences were studied. The results were also compared against the predictions from a modified EMI SE model. The predicted trends of SE value and frequency dependence were consistent with the experimental results, revealing that adjusting the number of BP layers and appropriate arrangement of the BP conducting layers and insulators can increase the EMI SE from 45 dB to close to 100 dB owing to the utilization of the double-shielding effect.

Structural anomalies associated with antiferromagnetic transition of single-component molecular metal [Au(tmdt)2].

The crystal structure of the single-component molecular metal [Au(tmdt)(2)] was examined by performing powder X-ray diffraction experiments in the temperature range of 9-300 K using a synchrotron radiation source installed at SPring-8. The structural anomalies associated with antiferromagnetic transition were observed around the transition temperature (T(N) = 110 K). The continuous temperature dependence of the unit cell volume and the discontinuous change in the thermal expansion coefficient at T(N) suggested that the antiferromagnetic transition of [Au(tmdt)(2)] is a second-order transition. Au(tmdt)(2) molecules are closely packed in the (021) plane with two-dimensional lattice vectors of a and l (= 2a + b + 2c). The shortest intermolecular S...S distance along the a axis shows a sharp decrease at around T(N), while the temperature dependence of l exhibits a characteristic peak in the same temperature region. A distinct structure anomaly was not observed along the direction perpendicular to the (021) plane. These results suggest that the molecular arrangement in only the (021) plane changes significantly at T(N). Thus, the intermolecular spacing shows anomalous temperature dependence at around T(N) only along that direction where the neighboring tmdt ligands have opposite spins in the antiferromagnetic spin structure model recently derived from ab initio band structure calculations. The results of single-crystal four-probe resistance measurements on extremely small crystals (approximately 25 microm) did not show a distinct resistance anomaly at T(N). The resistance anomaly associated with antiferromagnetic transition, if at all present, is very small. The Au-S bond length decreases sharply at around 110 K; this is consistent with the proposed antiferromagnetic spin distribution model, where the left and right ligands of the same molecule possess opposite spin polarizations. The tendency of the Au-S bond to elongate with decreasing temperature is ascribed to the small energy gap between the pd sigma(-) (or SOMO + 1) and the asym-Lpi(d) (or SOMO) states of the Au(tmdt)(2) molecule.

Metallization of the single component molecular semiconductor [Ni(ptdt)2] under very high pressure.

The four-probe electrical resistivity measurements on a single-component molecular semiconductor [Ni(ptdt)(2)] (Ni(S(8)C(9)H(6))(2)) was performed up to 20.7 GPa by using a diamond anvil cell. A newly improved method was employed to reduce the effect of uniaxial pressure. The semiconducting behavior persisted up to 17.9 GPa. The pressure-induced metallization began to appear at 18.9 GPa, and the complete metallic behavior down to 1 K was observed at 19.9 GPa.

Syntheses, structures, magnetism, and optical properties of lutetium-based interlanthanide selenides.

Ln3LuSe6 (Ln = La, Ce), beta-LnLuSe3 (Ln = Pr, Nd), and LnxLu4-xSe6 (Ln = Sm, Gd; x = 1.82, 1.87) have been synthesized using a Sb2Se3 flux at 1000 degrees C. Ln3LuSe6 (Ln = La, Ce) adopts the U3ScS6-type three-dimensional structure, which is constructed from two-dimensional 2(infinity)[Ln3Se6](3-) slabs with the gaps between these slabs being filled by octahedrally coordinated Lu(3+) ions. The series of beta-LnLuSe3 (Ln = Pr, Nd) are isotypic with UFeS3. Their structures include layers formed from LuSe6 octahedra that are separated by eight-coordinate Ln(3+) (Ln = Pr, Nd) ions in bicapped trigonal prismatic environments. Sm1.82Lu2.18Se6 and Gd1.87Lu2.13Se6 crystallize in the disordered F-Ln2S3 type structure with the eight-coordinate bicapped trigonal prismatic Ln(1) ions residing in the one-dimensional channels formed by three different double chains via edge- and corner-sharing. These double chains are constructed from Ln(2)Se7 monocapped trigonal prisms, Ln(3)Se6 octahedra, and Ln(4)S6 octahedra, respectively. The magnetic susceptibilities of beta-PrLuSe3 and beta-NdLuSe3 follow the Curie-Weiss law. Sm1.82Lu2.18Se6 shows van Vleck paramagnetism. Magnetic susceptibility measurements show that Gd1.87Lu2.13Se6 undergoes an antiferromagnetic transition around 4 K. Ce3LuSe6 exhibits soft ferromagnetism below 5 K. The optical band gaps for La3LuSe6, Ce3LuSe6, beta-PrLuSe3, beta-NdLuSe3, Sm1.82Lu2.18Se6, and Gd1.87Lu2.13Se6 are 1.26, 1.10, 1.56, 1.61, 1.51, and 1.56 eV, respectively.

Critical role of water content in the formation and reactivity of uranium, neptunium, and plutonium iodates under hydrothermal conditions: implications for the oxidative dissolution of spent nuclear fuel.

The reactions of 237NpO2 with excess iodate under acidic hydrothermal conditions result in the isolation of the neptunium(IV), neptunium(V), and neptunium(VI) iodates, Np(IO3)4, Np(IO3)4.nH2O.nHIO3, NpO2(IO3), NpO2(IO3)2(H2O), and NpO2(IO3)2.H2O, depending on both the pH and the amount of water present in the reactions. Reactions with less water and lower pH favor reduced products. Although the initial redox processes involved in the reactions between 237NpO2 or 242PuO2 and iodate are similar, the low solubility of Pu(IO3)4 dominates product formation in plutonium iodate reactions to a much greater extent than does Np(IO3)4 in the neptunium iodate system. UO2 reacts with iodate under these conditions to yield uranium(VI) iodates solely. The isotypic structures of the actinide(IV) iodates, An(IO3)4 (An=Np, Pu), are reported and consist of one-dimensional chains of dodecahedral An(IV) cations bridged by iodate anions. The structure of Np(IO3)4.nH2O.nHIO3 is constructed from NpO9 tricapped-trigonal prisms that are bridged by iodate into a polar three-dimensional framework structure. Second-harmonic-generation measurements on a polycrystalline sample of the Th analogue of Np(IO3)4.nH2O.nHIO3 reveal a response of approximately 12x that of alpha-SiO2. Single-crystal magnetic susceptibility measurements of Np(IO3)4 show magnetically isolated Np(IV) ions.

Observation of three-dimensional fermi surfaces in a single-component molecular metal, [Ni(tmdt)2].

Rigorous evidence of metallicity of a molecular crystal consisting of single-component neutral molecules is disclosed by observing the Fermi surface through magnetic quantum oscillations. Torque magnetometry measurements of de Haas-van Alphen oscillatory signals in a single crystal of [Ni(tmdt)2] molecules (tmdt = trimethylenetetrathiafulvalenedithiolate) were performed by using a sensitive microcantilever at low temperatures in high magnetic fields to 45 T. The observed signals for all directions of magnetic field revealed unambiguously the presence of three-dimensional Fermi surfaces for both holes and electrons. The results are consistent with electronic band structure calculations for [Ni(tmdt)2].

A new organic superconductor, beta-(BDA-TTP)2GaCl4 [BDA-TTP = 2,5-(1,3-dithian-2-ylidene)-1,3,4,6-tetrathiapentalene].

The preparation, crystal structure and physical properties of beta-(BDA-TTP)2GaCl4 has been investigated; the salt exhibits superconductivity at 3.1 K (onset) under a hydrostatic pressure of 7.6 kbar.