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We describe a composite hydrogel containing an embedding coupled chemistry for light-sensitized catalytic reactions that enables chemo-mechanical actuation of poly(acrylic acid)-based gels. In these materials, a photosensitizer and catalyst—ruthenium trisbipyridine and iridium dioxide nanoparticles, respectively—are incorporated into the hydrogel where together, with visible light irradiation, they undergo a catalytic water-oxidation reaction that lowers the pH and induces a dissipative/chemically-driven strain change in the gel. To demonstrate the capacity for 3D chemo-mechanical actuation, a layer of non-pH responsive poly(2-hydroxyethyl methacrylate) is added to the photo-active composite gel to create a model bimorph actuator. Triggering and terminating the water-oxidation reaction leads to a programmatic expansion and contraction of the active layer, which induces different modes of biomimetic curling motions in the bimorph actuator in light and dark environments. The efficiency of this system is fundamentally limited by the system-level design, which provides no capacity to sustain a local pH gradient against diffusive mixing. Even so, if the initial pH of the background solution is reestablished either actively or passively between each reaction cycle, it is possible to realize multiple cycles of reversible actuation. We describe a thermodynamic analysis of this system which identifies specific features mediating efficiency losses and conceptual requirements for mesoscopic design rules for optimization of this system and for advancing soft actuation systems in general.

Rhenium-Nickel (RexNi100-x) based 3D metallic inverse opals (IOs) were realized via colloidal crystal templated electrodeposition from an aqueous electrolyte. By varying the electrodeposition parameters, x could be varied from 0 to 88. Under reducing conditions, the rhenium-rich IOs were structurally stable to temperatures of at least 1000 °C for 5 h and for at least 12 h after coating with a thin layer of Al2O3. This demonstrated level of thermal stability is significantly improved compared to previously reported electrodeposited refractory inverse opals with similar characteristic dimensions. A strong frequency dependence in the optical reflection, which ranged from ∼5% around 1.5 μm to ∼65% around 5 μm, is predicted by simulations and experimentally observed, indicating the potential of this structure as a high temperature spectrally selective optical absorber/emitter. The elastic modulus of the ReNi IO structure is ∼35 GPa and the hardness is ∼0.8 GPa. Both these properties are much higher than those of Ni inverse opals and other periodically porous materials with similar characteristic pore dimensions. We suggest this work provides a promising approach for thermally stable mesostructured materials for high temperature catalyst supports, refractory photonics and mechanical applications including high temperature filtration, and high temperature actuators.

Electrodeposition of lithium-ion battery cathodes enables ultraflexible, ultrathick, and high-power rechargeable batteries., Materials synthesis often provides opportunities for innovation. We demonstrate a general low-temperature (260°C) molten salt electrodeposition approach to directly electroplate the important lithium-ion (Li-ion) battery cathode materials LiCoO2, LiMn2O4, and Al-doped LiCoO2. The crystallinities and electrochemical capacities of the electroplated oxides are comparable to those of the powders synthesized at much higher temperatures (700° to 1000°C). This new growth method significantly broadens the scope of battery form factors and functionalities, enabling a variety of highly desirable battery properties, including high energy, high power, and unprecedented electrode flexibility.

Three dimensional microplasma photonic crystal (3D MPPhC) is first time realized through 3D printing method. The layerlayer building method is only one embodiment for building the microstructures to confine the plasma. The 3D MPPhC proposed here for achieving highly tunable and reconfigurable material systems for electromagnetic responses in the millimeter wave or extremely high frequency regimes. The plasma crystal periodic structure arrays confined in the microstructures have been successfully realized within a volume large than 16.25 cm3, for example, can serve as a reconfigurable bandpass filter, beam splitter or router, attenuator, or phase shifter for frequencies up to and beyond 1THz. The mm-wave transmission responses from 110 – 170 GHz have been recorded with the strong responses. The dynamic tunings are demonstrated through the addressability of the microplasma array in three dimensions, including electron density, collisional frequency and crystal latter constants. We believe the capability of controlling the arrays of microplasma as dynamic material in three dimensions, in combination of the isotropic geometry, provide the versatile abilities to control the electromagnetic responses including but not limited to photonic band gap. The details will be introduced in the conference.

Cation substitution of Bi

Nanohybrid anode materials for Na-ion batteries (NIBs) based on conversion and/or alloying reactions can provide significantly improved energy and power characteristics, while suffering from low Coulombic efficiency and unfavorable voltage properties. An NIB paper-type nanohybrid anode (PNA) based on tin sulfide nanoparticles and acid-treated multiwalled carbon nanotubes is reported. In 1 m NaPF6 dissolved in diethylene glycol dimethyl ether as an electrolyte, the above PNA shows a high reversible capacity of ≈1200 mAh g-1 and a large voltage plateau corresponding to a capacity of ≈550 mAh g-1 in the low-voltage region of ≈0.1 V versus Na+ /Na, exhibiting high rate capabilities at a current rate of 1 A g-1 and good cycling performance over 250 cycles. In addition, the PNA exhibits a high first Coulombic efficiency of ≈90%, achieving values above 99% during subsequent cycles. Furthermore, the feasibility of PNA usage is demonstrated by full-cell tests with a reported cathode, which results in high specific energy and power values of ≈256 Wh kg-1 and 471 W kg-1 , respectively, with stable cycling.

Significant efforts have been made over the past few decades to realize functional three-dimensional photonic crystal devices including zero-threshold lasers, waveguides, light-emitting diodes (LEDs), and solar cells; however, progress has been limited because of difficulties in creating three-dimensional photonic crystals from single-crystal materials. Most have been formed from polycrystalline materials and thus have generally exhibited poor electronic properties. Realization of materials containing complex three-dimensional mesostructures, in single-crystal form, remains a significant challenge. Here, we demonstrate the epitaxial growth of three-dimensionally mesostructured Cu2O by bottom-up electrodeposition through a 3D silica colloidal template. Not only is the templated Cu2O single crystal, but when the electrodeposition continues past the colloidal template, the crystallinity of the overlying solid Cu2O appears to be improved because the template blocks threading dislocations, resulting in substan...

An approach to the detection of ginsenosides in plant extracts and commercial products is developed on the basis of liquid chromatography/mass spectrometry. The approach was validated for two major ginsenosides F11 and RT5 quantified in extracts from Panax ginseng and Panax quinquefolius roots. The samples were analyzed by reversed-phase chromatography with a C18 adsorbent. For the registration of compounds, electrospray ionization in the mode of positive ions and tandem mass spectrometry detection system were used. The limits of detection in the multiple reaction monitoring mode were 10 and 20 ng/mL. Linearity with the correlation coefficient > 0.999 was observed for the range 50–2000 ng/mL.

An approach to the simultaneous registration of ginsenosides in herbal extracts and commercial products was developed on the basis of liquid chromatography/mass spectrometry. The approach was validated for four major ginsenosides: Rg1, Rb1, Rf, and Re determined in extracts from roots of Panax ginseng, a phyto-formulation and a tea produced from the roots. The limits of detection for two applied detection modes belong to the range 0.001–0.01 μg/mL. Samples were analyzed by reversed-phase chromatography with a C18 adsorbent. Electrospray ionization in the positive ion mode and a hybrid linear-trap tandem mass spectrometry detection system were used to monitor compounds.

A rapid single-run analytical approach suitable to achieve a comprehensive characterization of ginsenosides - the main bioactive compounds present in plant materials from Panax species and ginseng-based products - was developed. The method is based on high-performance liquid chromatography coupled with electrospray positive ionization linear ion trap mass spectrometry (HPLC/ESI-LITMS). The main ions in the ESI-LITMS spectra were attributed to molecular adducts with sodium and potassium and fragments corresponding to cleavage of the glycosidic bonds. The simplicity of the approach allows laborious sample preparation and sophisticated spectral information-dependent acquisition to be avoided, and provides an opportunity for rapid screening. The method may replace existing HPLC-DAD profiling approaches. The results of this study indicate that HPLC/ESI-LITMS is applicable for quality control purposes on processed products and allows the rapid and direct identification of ginsenosides in crude plant extracts.

Here we demonstrate, via a modified transfer- printing technique, that electrochemically fabricated porous silicon (PSi) distributed Bragg reflectors (DBRs) can serve as the basis of high-quality hybrid microcavities compatible with most forms of photoemitters. Vertical microcavities consisting of an emitter layer sandwiched between 11- and 15-period PSi DBRs were constructed. The emitter layer included a polymer doped with PbS quantum dots, as well as a heterogeneous GaAs thin film. In this structure, the PbS emission was significantly redistributed to a 2.1 nm full-width at half- maximum around 1198 nm, while the PSi/GaAs hybrid microcavity emitted at 902 nm with a sub-nanometer full-width at half-maximum and quality-factor of 1058. Modification of PSi DBRs to include a PSi cavity coupling layer enabled tuning of the total cavity optical thickness. Infiltration of the PSi with Al2O3 by atomic layer deposition globally red-shifted the emission peak of PbS quantum dots up to ∼18 nm (∼0.9 nm per cycle), while introducing a cavity coupling layer with a gradient optical thickness spatially modulated the cavity resonance of the PSi/GaAs hybrid such that there was an ∼30 nm spectral variation in the emission of separate GaAs modules printed ∼3 mm apart.

We present a facile microfluidic method for forming narrow chemical gradients in polymer brushes. Co-flow of an alkylating agent solution and a neat solvent in a microfluidic channel forms a diffusion-driven concentration gradient, and thus a gradient in reaction rate at the interface of the two flows, leading to a quaternization gradient in the underlying poly(2-(dimethylamino)ethyl methacrylate) polymer brush. The spatial distribution of the quaternized polymer brush is characterized by confocal Raman microscopy. The quaternization gradient length in the polymer brush can be varied with the injection flow rate and the distance from the co-flow junction. A chemical gradient in the polymer brush as narrow as 5 μm was created by controlling these parameters. The chemical gradient by laminar co-flow is compared with numerical calculations that include only one adjustable parameter: the reaction rate constant of the polymer brush quaternization. The calculated chemical gradient agrees with the experimental data, which validates the numerical procedures established in this study. Flow of multiple laminar streams of reactive agent solutions enables single-run fabrication of brush gradients with more than one chemical property. As one example, four laminar streams-neat solvent/benzyl bromide solution/propargyl bromide solution/neat solvent-generate multistep gradients of aromatic and alkyne groups. Because the alkyne functional group is a click-reaction available site, the alkyne gradient could allow small gradient formation with a wide variety of chemical properties in a polymer brush.

We report a general diffusion based method to form micrometer-scale lateral chemical gradients in polymer brushes via selective alkylation. A quaternized brush gradient is derived from a concentration gradient of alkylating agent formed by diffusion in permeable media around a microchannel carrying the alkylating agent. Polymer brushes containing both charge and aromatic gradients are formed using the alkylating agents, methyl iodide and benzyl bromide, respectively. The gradients are quantitatively characterized by confocal Raman spectroscopy and qualitatively by fluorescence microscopy. The length and gradient strength can be controlled by varying the diffusion time, concentrations, and solvents of the alkylating agent solutions. This microfluidic brush gradient generation method enables formation of 2-D chemical potential gradients with a diversity of shapes.

Hintergrund Die Bestimmung des prostataspezifischen Antigens (PSA) zur Fruherkennung des Prostatakarzinoms erfolgt auch durch Hausarzte und Internisten (H/I). Da Ergebnisse uber das diesbezugliche Vorgehen deutscher H/I und die Einordnung dieser Daten im internationalen Vergleich derzeit jedoch nicht vorliegen, wurde dies anhand einer Fragebogenstudie erstmalig untersucht.

A spiropyran mechanophore (force-sensitive molecule), which is fluorescent in its mechanically activated state, is used to investigate swelling-induced mechanochemistry in cross-linked poly(methyl methacrylate). The spiropyran is incorporated as a cross-linker. A correlation is observed between solvent-induced polymer swelling and fluorescence intensity, suggesting that the forces during swelling are sufficient to drive the electrocyclic ring-opening of spiropyran to its colored and fluorescent merocyanine form. Control experiments and solvatochromic studies validate that activation is indeed due to swelling-induced mechanical forces and not solvent effects. Systematic studies varying solvents and cross-linking densities provide insight into how altering swelling parameters influences the mechanophore response at the molecular level.

In this paper, we argue that pot-making should be considered in its broader landscape to reveal not only its articulation with the many other quotidian tasks undertaken by a community but also how ancient people oriented themselves in that landscape. We address this point in the context of two small Neolithic communities in southern Calabria, Italy, by treating archaeological ceramics as congealed taskscapes and implementing a novel methodology to unravel the interactions among people, materials, and landscapes. We examine how clay sources are distributed in the local landscape, what the qualities of the clays within them are, and what specific materials the Neolithic potters used in making their pots. We ask not only where in the landscape potters went to get their raw materials but also where they did not go. Their selective engagement with the landscape reveals a social understanding of parts of the landscape considered “appropriate” and “relevant” to pot-making (inland areas) and parts that were not (coastal areas). We also ask what other tasks potters could have undertaken while collecting clays. The co-occurrence of resources in the landscape highlights the need to consider the interlocking of various daily tasks and reveals which tasks could have been perceived as socially related. By explicitly considering the task of pot-making in its landscape, this paper reveals the relational and mutually constitutive articulation of both in everyday life.

Inexorable demand for increasing bandwidth is driving future wireless communications systems into the 100 GHz–1 THz region, thereby fueling demand for new sources and modulators but also complementary devices such as resonators, phase shifters, and filters. Few such devices exist at present, and the electromagnetic properties of those available at millimeter-wavelengths are generally fixed and characterized by broad (i.e., low Q) resonances. We introduce a class of 3D plasma/metal/dielectric photonic crystals (PPCs), operating in the 120–170 GHz spectral range, that are dynamic (tunable and reconfigurable at electronic speeds) and possess attenuation and transmission resonances with bandwidths below 50 MHz. Interference between sublattices of the crystal, which controls the resonance line shapes, is manipulated through the crystal structure. Incorporating Bragg arrays of low-temperature plasma microcolumns into a dielectric/metal scaffold that is itself a static crystal forms two interwoven and electromagnetically coupled crystals. Plasma-scaffold lattices produce multiple, narrowband attenuation resonances that shift monotonically to higher frequencies by as much as 1.6 GHz with increasing plasma electron density. Controlling the longitudinal geometry of the PPC through electronic activation of successive Bragg planes of plasma columns reveals an unexpected double-crystal symmetry interaction at 138.4 GHz and resonance Q values above 5100. The introduction of point or line defects into plasma column/polymer/metal crystals increases transparency at resonances of the scaffold (Borrmann effect) and yields Fano line shapes characteristic of coupled resonators. The experimental results suggest the suitability of PPC-based metamaterials for applications including multichannel communications, millimeter-wave spectroscopy, and fundamental studies of multiple, coupled resonators.

In Fig. 4c of this Article, the scale bar units were incorrectly stated as ‘μV’; the correct units are ‘mV’. The figure has now been amended accordingly.

Graphene based electrical conductors are under consideration for numerous applications in energy storage, energy conversion devices, electronics and sensors. Here, we report a facile and versatile method for fabrication of graphene based composite microwires ranging from ∼20 to 250 μm in diameter via size reduction during dehydration of extruded larger diameter graphene oxide-loaded agarose hydrogel fibers. The graphene oxide is effectively reduced to graphene by chemical and thermal treatment. After dehydration and reduction, the resulting graphene composite microwires exhibit high electrical conductivities of up to 1.8 S m−1.

ZusammenfassungEin 15-jähriger, weiblicher Kalifornischer Seelöwe (Zalophus californianus) mit progressiver Lähmung der Hintergliedmaßen und einer chronischen Hautwunde wurde zur Untersuchung vorgestellt. Die neurologische Untersuchung mit dem Befund einer Paraparese der Hinterhand wurde durch eine magnetresonanztomographische Untersuchung ergänzt. In der MRT-Darstellung der Hals- und Brustwirbelsäule zeigte sich zwischen dem siebten Halswirbel (C7) und dem zweiten Brustwirbel (Th2) eine gut abgrenzbare, die Muskulatur infiltrierende Masse, die durch das Foramen intervertebrale zwischen C7 und Th1 in den Wirbelkanal zog und das Rückenmark komprimierte und verdrängte. Die pathologische Untersuchung ergab eine herdförmige eitrige Meningitis infolge eines weitreichenden Fistelprozesses. Den Ausgangspunkt stellte die chronische Hautwunde dar, die mit Escherichia coli var. haemolytica und Clostridium perfringens infiziert war.

This Perspective overviews many of the developments in templated porous three-dimensional photonics, with a particular focus on functional architectures, and provides suggestions for future opportunities for research. A significant diversity of 3D structures is available today with characteristic dimensions appropriate for providing strong light–matter interactions, in no small part due to recent advances in 3D patterning techniques. However, the optical functionality of these structures has generally remained limited. Advances in materials chemistry have the opportunity to dramatically increase the function of templated 3D photonics, and a few examples of highly functional templated 3D photonics for sensing, solar energy harvesting, optical metamaterials, and light emission are presented as first examples of success.

A sensitive and simple method for the methotrexate quantification was developed using aminopterin as internal standard. Methotrexate is an anticancer agent that is widely used in a variety of human cancers including primary central nervous system lymphoma. The compound was quantified by liquid-chromatography coupled to electrospray ionization (positive ion-mode) low-energy collision dissociation-tandem mass spectrometry. Quantitative detection was by multiple reaction monitoring of the transitions of the [M+H]+ ion of MTX to its common product ion at m/z 308.4 and of aminopterin at m/z 441.2→m/z 294.0. The method demonstrated linearity over at least three orders of magnitude and had a detection limit of 1ng/ml for methotrexate. A run time of less than 8.0min for each sample made it possible to analyze a large number of human saliva samples per day. Application of this procedure was demonstrated to a saliva excretion study of methotrexate on the samples obtained after an intravenously administration of 1mg/kg/dose of methotrexate to six patients with acute lymphoblastic leukemia.

We manufacture large-area plasmonic structures featuring 3-dimensional chirality by colloidal nanohole lithography. By varying the polar rotating speed of the samples during gold evaporation, we can fabricate spiral-type ramp nanostructures. The optical properties show chiroptical resonances in the 100 to 400 THz frequency region (750 to 3000 nm), with circular dichroism values of up to 13%. Our method offers a simple low-cost manufacturing method of cm(2)-sized chiral plasmonic templates for chiroptical applications such as stereochemical enantiomer sensors.

Spiropyran (SP) mechanophore was synthesized into the soft or hard phase of segmented polyurethanes (SPU) and used as a molecular probe of force and orientation. Upon either tensile stretching or irradiation with UV light the SP-linked segmented polyurethane (SP-SPU) adopt a deep purple coloration and are fluorescent, demonstrating the force and UV-induced formation of the open merocyanine (MC) form of the mechanophore. Order parameters calculated from the anisotropy of the fluorescence polarization of merocyanine (MC) were used to characterize the orientation in each phase. Exploiting the ability of SP to be force activated, the SP-SPUs were also mechanically activated to track the force and orientation in each domain of segmented polyurethane during uniaxial tensile loading.

Ginsenosides are the main bioactive compounds of the Panax plant genus. Ginseng and its analogues are widely used to produce traditional medicines in China, Korea, Japan, United States, and the Russian Far East. For more than 40 years, many researchers developed methods of identifying and determining and ginsenosides in plant tissues, extracts, and commercial products. Various extraction methods were used to isolate these compounds from plant materials. The separation of ginsenosides was conducted with methods such as gas chromatography, thin-layer chromatography, and high-performance liquid chromatography (HPLC). The HPLC method was used predominantly. Spectrophotometric and fluorescent monitoring and, later, light scattering and mass-spectrometry coupled with HPLC were used to determine ginsenosides. The most recent variants of these methods are presented in this review, together with a critical evaluation of the published results.

Because interfaces impede phonon transport of thermal energy, nanostructuring can transform fully dense solids into ultralow thermal conductivity materials. Here we report a simple self-assembly approach to synthesizing organoclay nanolaminates with cross-planar thermal conductivities below 0.10 W m(-1) K(-1)-a 5-fold decrease compared to unmodified clay. These organoclays are produced via alkylammonium cation exchange with colloidally dispersed montmorillonite clay sheets followed by solvent casting. Time-domain thermoreflectance (TDTR) is used to evaluate the thermal conductivity of the organoclay nanolaminates. Variations in both organic layer thickness and cation chemistry are investigated. At these interface densities (1.0-1.5 interfaces/nm), we demonstrate that thermal conductivity is relatively independent of nanolaminate spacing. A simple series resistance model describes the behavior and gives an interfacial thermal conductance value of ≈150 MW m(-2) K(-1) for the organic/clay interface, consistent with similar organic-inorganic interfaces. The wide range of compositional substitutions and structural variations possible in these materials, make organoclays a versatile new platform for investigating the underlying physics of nanolaminate structures.

This work represents two approaches of the determination of V-gases that are stable oxidative products in the environment. Four N,N-(dialkyl)aminoethanesulfonic acids: methyl-, ethyl-, n-propyl- and iso-propyl- (DMT, DET, DPT, and DIT, respectively) which are known as oxidative degradation products (DPs) of nerve agents were determined in seven different natural water samples using high-performance liquid chromatography-mass spectrometry (HPLC-MS) and capillary electrophoresis (CE) with direct ultraviolet (UV) detection (CE-UV). Linear response ranges were approximately two orders of magnitude for these four compounds. Limits of detection of these substances were 0.015–0.025 mg/L for HPLC-MS and 1.5–2 mg/L for CE-UV determination. Successful development of the technique may lead to a simple sensor for V-gases DPs that could be implemented and used at sensitive locations throughout the world. Forensic analysis of DMT, DET, DPT, and DIT as specific markers of different types of V-gases performed by these tw...

Colloidal crystals have attracted considerable attention due to their deterministic three-dimensional (3D) structures, interesting optical properties and ease of assembly. [ 1–5 ] The use of colloidal crystals as templates to impart periodic patterns into various materials has been broadly employed to create, for example, unique optoelectronic devices, [ 6,7 ] sensors, [ 8–12 ] and energy storage devices. [ 13,14 ] The general motivation for templating is to utilize the opals’ interconnected 3D structure to defi ne the 3D structure of a material which is inherently diffi cult to form into a highly regular 3D structure on its own. A single replication yields a structure which is an inverse of the colloidal template, and a double replication yields the original structure of the template. This process is only successful if the colloidal template can withstand the deposition conditions of the material to be templated and there exist conditions whereby the original template can be removed without damaging the templated material. Given that the most popular template, silica, can only be removed with hydrofl uoric acid or strong base, chemicals that dissolve many materials, this can be challenging. Polymer templates (e.g. polystyrene or poly(methyl methacrylate)) are easy to remove, but cannot withstand high temperature deposition strategies, limiting their use. [ 2 ] Thermally-stable colloids which could be removed under orthogonal conditions, i.e., conditions that do not damage the templated material, would allow currently inaccessible materials templating strategies. Additionally, if the templates contained additional desirable structural complexities (e.g. a high surface area) which are replicated in the templated material, additional applications may emerge; for example, dye sensitized solar cells require high-surface area electrodes, [ 15 ] as do many other catalytic devices. In this communication, we fi rst demonstrate the fabrication of high-quality

Typical colloid-polymer composites have particle diameters much larger than the polymer mesh size, but successful integration of smaller colloids into a large-mesh network could allow for the realization of new colloidal states of spatial organization and faster colloid motion which can allow the possibility of switchable re-configuration of colloids or more dramatic stimuli-responsive property changes. Experimental realization of such composites requires solving non-trivial materials selection and fabrication challenges; key questions include composition regime maps of successful composites, the resulting structure and colloidal contact network, and the mechanical properties, in particular the ability to form a network and retain strain stiffening in the presence of colloids. Here, we study these fundamental questions by formulating composites with fluorescent (though not stimuli-responsive) carboxylate modified polystyrene/latex (CML) colloidal particles (diameters 200 nm and 1000 nm) in bovine fibrin networks (a semi-flexible biopolymer network with mesh size 1-5 μm). We describe and characterize two methods of composite preparation: adding colloids before fibrinogen polymerization (Method I), and electrophoretically driving colloids into a network already formed by fibrinogen polymerization (Method II). We directly image the morphology of colloidal and fibrous components with two-color fluorescent confocal microscopy under wet conditions and SEM of fixed dry samples. Mechanical properties are studied with shear and extensional rheology. Both fabrication methods are successful, though with trade-offs. Method I retains the nonlinear strain-stiffening and extensibility of the native fibrin network, but some colloid clustering is observed and fibrin network integrity is lost above a critical colloid concentration that depends on fibrinogen and thrombin concentration. Larger colloids can be included at higher volume fractions before massive aggregation occurs, indicating surface interactions as a limiting factor. Method II results in a loss of measurable strain-stiffening, but colloids are well dispersed and template along the fibrous scaffold. The results here, with insight into both structure and rheology, form a foundational understanding for the integration of other colloids, e.g. with stimuli-responsive functionalities, into semi-flexible networks.

We measure the thermal conductivity, heat capacity and sound velocity of thin films of five polymers, nine polymer salts, and four caged molecules to advance the fundamental understanding of the lower and upper limits to heat conduction in amorphous macromolecules. The thermal conductivities vary by more than one order of magnitude, from $0.06\phantom{\rule{0.16em}{0ex}}\mathrm{W}\phantom{\rule{0.16em}{0ex}}{\mathrm{m}}^{\ensuremath{-}1}\phantom{\rule{0.16em}{0ex}}{\mathrm{K}}^{\ensuremath{-}1}$ for [6,6]-phenyl-C71-butyric acid methyl ester to $0.67\phantom{\rule{0.16em}{0ex}}\mathrm{W}\phantom{\rule{0.16em}{0ex}}{\mathrm{m}}^{\ensuremath{-}1}\phantom{\rule{0.16em}{0ex}}{\mathrm{K}}^{\ensuremath{-}1}$ for poly(vinylphosphonic acid calcium salt). Minimum thermal conductivity calculated from the measured sound velocity and effective atomic density is in good agreement with the thermal conductivity of macromolecules with various molecular structures and intermolecular bonding strength.

As potential high-performance anodes for Li-ion batteries (LIBs), hierarchical heteronanostructures consisting of TiNb

We report measurements and modeling of thermal conductivity in periodic three-dimensional dielectric nanostructures, silicon inverse opals. Such structures represent a three-dimensional "phononic crystal" but affect heat flow instead of acoustics. Employing the Stober method, we fabricate high quality silica opal templates that on filling with amorphous silicon, etching and recrystallizing produce silicon inverse opals. The periodicities and shell thicknesses are in the range 420-900 and 18-38 nm, respectively. The thermal conductivity of inverse opal films are relatively low, ~0.6-1.4 W/mK at 300 K and arise due to macroscopic bending of heat flow lines in the structure. The corresponding material thermal conductivity is in the range 5-12 W/mK and has an anomalous ~T(1.8) dependence at low temperatures, distinct from the typical ~T(3) behavior of bulk polycrystalline silicon. Using phonon scattering theory, we show such dependence arising from coherent phonon reflections in the intergrain region. This is consistent with an unconfirmed theory proposed in 1955. The low thermal conductivity is significant for applications in photonics where they imply significant temperature rise at relatively low absorption and in thermoelectrics, where they suggest the possibility of enhancement in the figure of merit for polysilicon with optimal doping.

PURPOSE OF THE ARTICLE. In the past decades a number of extraction methods for biologically active compounds of ginseng coupled with different detection techniques were created. For HPLC-MS profiling of these compounds in plant material and related products a fast non-destructive way to extract ginsenosides from plant materials and ginseng products based on ultrasound-assisted extraction was developed. FINDINGS. Calculated by means of "Added-Found" approach recoveries of ginsenosides Rg1, Rb1, Rc from ginseng root and model sample known to be free of analytes ranged from 80 to 110 %. The effect on the recovery of the following factors: the composition of the extracting mixture, the volume of the mixture and the number of successive extractions was studied. The extraction in case of using 50-70 % methanol/ethanol water mixtures was 1.5-2 times more effective than with 10-20 % mixtures. CONCLUSIONS. After optimization developed method of extraction without subsequent evaporation and reconstitution of the extract was used in combination with HPLC-MS determination of ginsenosides in various objects with a complex matrix. Keywords : ultrasound-assisted extraction, ginsenosides, Panax ginseng , HPLC- MS/MS (Russian) DOI: http://dx.doi.org/10.15826/analitika.2013.17.4.012 A.N. Stavrianidi, I.A. Rodin, A.V. Braun, O.A. Shpigun Lomonosov Moscow State University , Moscow, Russian Federation

According to the German social insurance code §20 Sec. 1, statutory health insurance companies can reimburse up to 80% of costs incurred by primary prevention programs in physical activity, nutrition, stress management and drug consumption. Whether and how many general practitioners (GPs) provide their patients with information on such programs as part of their own practice is unknown. In this study, we investigate to which primary prevention programs primary care physicians refer their patients and whether they take into account reimbursability of programs.Between November 2010 and February 2011, all GPs with a practice in Berlin (n=1 168) received a questionnaire that assessed if patients were referred to prevention programs and the type of programs they were referred to, if they ensured they are reimbursable and if they themselves offered prevention programs. Descriptive statistics and multivariate logistic regression was used for analysis.Of 474 respondents (response rate: 41%), 67% were female. Of the respondents, 22% offered reimbursable prevention programs and 42% at out-of-pocket expense. Patients were referred to reimbursable programs by 63%. GPs younger than 50 were twice as likely to offer reimbursable programs in their practice compared to those older than 50 (OR=1.7; 95% KI 1.1-2,8; p-value 0.025).A successful implementation of the new German prevention law needs awareness among GPs about reimbursable prevention programs, which may be lacking in some groups.Nach dem fünften Sozialgesetzbuch §20 Abs. 1 können die Gesetzlichen Krankenversicherungen (GKV) Kosten für primärpräventive Programme im Bereich Bewegung, Ernährung, Stressmanagement und Suchtmittelkonsum bis zu 80% rückerstatten. Inwieweit Allgemeinärzte in ihrer Praxis auf solche Angebote verweisen oder selbst im Primärpräventionsbereich Programme nach §20 oder als individuelle Gesundheitsleistungen (IGeL) anbieten, ist unbekannt. Ziel der hier dargestellten Befragung war es, zu erfassen, an welche Anbieter sie für Primärpräventionsangebote verweisen und inwieweit sie dabei berücksichtigen, ob diese erstattungsfähig sind. Zusätzlich wurde untersucht, inwieweit Allgemeinärzte/innen individuelle Gesundheitsleistungen (IGeL) in diesen Bereichen anbieten.Zwischen November 2010 und Februar 2011 erhielten alle Allgemeinärzte mit Praxissitz in Berlin (n=1 168) einen Fragebogen, der erfasste ob und auf welche Präventionsprogramme sie ihre Patienten hinweisen, inwieweit sie dabei berücksichtigen, dass diese erstattungsfähig sind und ob sie Präventionsprogramme nach §20 oder als IGeL anbieten. Deskriptive Statistik und multivariate logistische Regression wurden durchgeführt.Von 474 Teilnehmenden (Rücklaufquote: 41%) waren 67% weiblich. In der eigenen Praxis boten 22% der Allgemeinärzte Präventionsprogramme nach §20 und 42% IGeL an. Von den Befragten gaben 63% an, darauf zu achten, dass Präventionsprogramme teilerstattungsfähig sind. Allgemeinärzte, die jünger als 50 Jahre alt waren, boten fast doppelt so häufig Präventionsprogramme nach §20 als Ärzte über 50 Jahren an (OR=1,7; 95% KI 1,1–2,8; p-Wert 0,025).Eine erfolgreiche Umsetzung des neuen Präventionsgesetztes erfordert ein Wissen zu teilerstattungsfähigen Präventionsprogrammen bei Ärzten. Hier ist zum Teil ein Informationsdefizit vorhanden.

High-operating-temperature direct ink writing (HOT-DIW) of mesoscale architectures that are composed of eutectic silver chloride-potassium chloride. The molten ink undergoes directional solidification upon printing on a cold substrate. The lamellar spacing of the printed features can be varied between approximately 100 nm and 2 µm, enabling the manipulation of light in the visible and infrared range.

High volumetric energy density secondary batteries are important for many applications, which has led to considerable efforts to replace the low volumetric capacity graphite-based anode common to most Li-ion batteries with a higher energy density anode. Because most high capacity anode materials expand significantly during charging, such anodes must contain sufficient porosity in the discharged state to enable the expansion, yet not excess porosity, which lowers the overall energy density. Here, we present a high volumetric capacity anode consisting of a three-dimensional (3D) nanocomposite formed in only a few steps which includes both a 3D structured Sn scaffold and a hollow Sn sphere within each cavity where all the free Sn surfaces are coated with carbon. The anode exhibits a high volumetric capacity of ∼1700 mA h cm(-3) over 200 cycles at 0.5C, and a capacity greater than 1200 mA h cm(-3) at 10C. Importantly, the anode can even be formed into a commercially relevant ∼100 μm thick form. When assembled into a full cell the anode shows a good compatibility with a commercial LiMn2O4 cathode. In situ TEM observations confirm the electrode design accommodates the necessary volume expansion during lithiation.

A gyroid structure is a distinct morphology that is triply periodic and consists of minimal isosurfaces containing no straight lines. We have designed and synthesized amorphous silicon (a-Si) mid-infrared gyroid photonic crystals that exhibit a complete bandgap in infrared spectroscopy measurements. Photonic crystals were synthesized by deposition of a-Si/Al2O3 coatings onto a sacrificial polymer scaffold defined by two-photon lithography. We observed a 100% reflectance at 7.5 \mum for single gyroids with a unit cell size of 4.5 \mum, in agreement with the photonic bandgap position predicted from full-wave electromagnetic simulations, whereas the observed reflection peak shifted to 8 um for a 5.5 \mum unit cell size. This approach represents a simulation-fabrication-characterization platform to realize three-dimensional gyroid photonic crystals with well-defined dimensions in real space and tailored properties in momentum space.

Porous metals are used in interfacial transport applications that leverage the combination of electrical and/or thermal conductivity and the large available surface area. As nanomaterials push toward smaller pore sizes to increase the total surface area and reduce diffusion length scales, electron conduction within the metal scaffold becomes suppressed due to increased surface scattering. Here we observe the transition from diffusive to quasi-ballistic thermal conduction using metal inverse opals (IOs), which are metal films that contain a periodic arrangement of interconnected spherical pores. As the material dimensions are reduced from ∼230 nm to ∼23 nm, the thermal conductivity of copper IOs is reduced by more than 57% due to the increase in surface scattering. In contrast, nickel IOs exhibit diffusive-like conduction and have a constant thermal conductivity over this size regime. The quasi-ballistic nature of electron transport at these length scales is modeled considering the inverse opal geometry, surface scattering, and grain boundaries. Understanding the characteristics of electron conduction at the nanoscale is essential to minimizing the total resistance of porous metals for interfacial transport applications, such as the total electrical resistance of battery electrodes and the total thermal resistance of microscale heat exchangers.

A deterministic graphene-sandwiched Li-ion battery electrode consisting of an integrated 3D mesostructure of electrochemically active materials and graphene is presented. As demonstrations, electrodes with active nanomaterials that coat (V2 O5 @graphene@V2 O5 cathode) or are coated by (graphene@Si@graphene anode) graphene are fabricated. These electrodes exhibit high capacities and ultralong cycle lives (the cathode can be cycled over 2000 times with minimal capacity fade).

A new approach to qualitative analysis of ginsenosides in challenging matrices was developed on the basis of high-performance liquid chromatography/tandem mass spectrometry. Using the extracts from samples of ginseng tea, the approach was validated. Analysis of extracts was carried out using a reversed-phase chromatography with SB-C18 sorbent. For compound identification, electrospray ionization and a quadrupole/linear ion trap mass-spectrometer in different modes were used. A meticulous study of the fragmentation of ginsenosides in the linear ion trap and its application for analysis of these compounds was performed in this work. The accuracy of the identification was proven with standards of ginsenosides Rb1, Rg1, Re, Rf, Rd, Rb2, Rb3 and Rc. Copyright © 2012 John Wiley & Sons, Ltd.

An approach is developed for the simultaneous determination of salidroside, rosarin, and rosavin in extracts from plant based on liquid chromatography/mass spectrometry; the detection limits of the method are 2, 4, and 6 ng/mL for salidroside, rosavin, and rosarin, respectively. The method was validated using real extracts from Rhodiola rosea rhizome. The analysis of extracts was accomplished by reversed-phase chromatography with a SB-C18 stationary phase. The analytes were detected by tandem mass spectrometry with electrospray ionization in the multiple reaction monitoring mode for negative ions.

Forensic scientists are often asked to physically compare duct tape samples found in association with criminal activity. This study was designed to statistically evaluate the error and accuracy rates associated with duct tape physical end matching. The experimental design consisted of a blind study in which three researchers independently analyzed eight types of tape subjected to four methods of separation. The lowest mean accuracy observed was 98.15%, the highest mean false-positive rate observed was 3.33%, and the highest mean false-negative rate was 2.67%. Overall, high accuracy with low false-positive and false-negative error rates were observed. This study confirms the use of physical end matching in identifying duct tape samples as matching or nonmatching and that the differences between analysts, brands, tape grades, tape color, and methods of separation have varying contributions to misidentifications and inconclusive results. This study also demonstrates the importance of peer review in duct tape analysis.

Polymers that respond in a productive fashion to their environment are under active development as they offer significant advantages over traditional materials. For example, polymers with the ability to self-heal and recover a significant fraction of their initial properties after being subjected to a damage event are of significant interest. Here we study the effect of healing agent viscosity and catalyst activity on self-healing at and near room temperature. The viscosity of the PDMS healing agent was varied from 14 to 40 000 cP, and the tin-based catalysts di-n-butyltin dilaurate, dimethyl-dineodacanoate tin, di-n-butyl bis(2-ethylenehexanoate), tin II oleate, and tetrakis(acetoxydibutyl tinoxy)silane were studied. Both vinyl ester and epoxy matrices were investigated. By optimizing the viscosity of the PDMS healing agent and the catalytic activity, as well as selection of the appropriate adhesion promoter, a PDMS-based self-healing system which healed at room temperature was obtained.