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Vanadium–oxygen species are very harmful to the environment and human health, and also some vanadium–oxygen species have good biological and biomedical effects to human beings. Thus, the study of vanadium–oxygen species is very significant. The types of V–O species are very complex. So far, however, the various structures of V–O species cannot be identified clearly. In this work, the surface‐enhanced Raman spectroscopy (SERS) was used to study vanadium–oxygen species in aqueous solution directly. The SERS spectra with high enhancement factor (EF) and detail information were obtained by the enhancement substrates such as gold nanoparticles (AuNPs), Ag mirror, the Au‐deposited Pt electrodes, and rough Au electrodes. The structures of vanadium‐oxygen species in solutions with different concentration and pH had been well‐characterized firstly by the combination of SERS experiments with density functional theory (DFT) calculations. This work will promote the basic study of the V–O species, and it is also a promotion for the SERS and analytical chemistry. [ABSTRACT FROM AUTHOR]

Alcohol consumption around the time of conception is highly prevalent in Western countries. Exposure to ethanol levels during gestation has been associated with altered development of the mesolimbic reward pathway in rats and increased propensity to addiction, however the effect of exposure only around the time of conception is unknown. The current study investigated the effects of periconceptional alcohol exposure (PC:EtOH) on alcohol and palatable food preferences and gene expression in the ventral tegmental area (VTA) and the nucleus accumbens of the adult offspring. Rats were exposed to a liquid diet containing ethanol (EtOH) (12.5% vol/vol) or a control diet from 4 days before mating until 4 days after mating. PC:EtOH had no effect on alcohol preference in either sex. At 15 months of age, however, male PC:EtOH offspring consumed more high-fat food when compared with male control offspring, but this preference was not observed in females. Expression of the dopamine receptor type 1 (Drd1a) was lower in the VTA of male PC:EtOH offspring compared with their control counterparts. There was no effect of PC:EtOH on mRNA expression of the µ-opioid receptor, tyrosine hydroxylase (Th), dopamine receptor type 2 (Drd2) or dopamine active transporter (Slc6a3). These data support the hypothesis that periconceptional alcohol exposure can alter expression of key components of the mesolimbic reward pathway and heighten the preference of offspring for palatable foods and may therefore increase their propensity towards diet-induced obesity. These results highlight the importance of alcohol avoidance when planning a pregnancy. [ABSTRACT FROM PUBLISHER]

Field-effect transistors (FETs) employing the solution-processed metal oxides as dielectrics have shown excellent performance on rigid silicon substrate. However, there have been very limited reports on FETs with solution-processed, thermal-annealed metal oxide dielectrics on low-cost flexible substrates. To date, to our knowledge there is almost no report on flexible FETs having the similar or better performance than the FETs on Si substrate with solution-processed, thermal-annealed metal oxides as dielectrics. Herein, flexible pentacene-based organic FETs have been demonstrated with polystyrene (PS)-modified, solution-processed yttrium oxide (Y2O3), hafnium oxide (HfO2), or aluminum oxide (Al2O3) as dielectrics on commercially available aluminum (Al) foil substrates. The transistors exhibit a good carrier mobility ( µ), a large on/off current ratio ( Ion/off), a low threshold voltage ( VT), and a small subthreshold swing (SS) at a low-operation voltage (−4 V), which is comparable with the device performance on rigid Si substrate. Therefore, the excellent electrical performance of the FETs on commercially available Al foil substrate, together with the virtue of light-weight, makes the devices possess the promising potential for various electronic system applications. [ABSTRACT FROM AUTHOR]

The relationship between the adhesive bonding strengths and the bonding areas (sizes) is important for material and structural designs, because adhesive bonding is widely used not only in small scale electronic devices, but also in large-scale composite–metal joints of modern aircraft/ship structures. Therefore, a systematic experimental investigation on adhesive bonding strengths of polymer/polymer, metal/metal, and polymer/metal joints was conducted. Results show that the size effect of the bonding strengths is small for the current bonding areas (from 30 to 300 mm2), which are widely employed in most of the test standards for engineering designs. [ABSTRACT FROM PUBLISHER]

It is found that ultrathin poly(3-hexylthiophene) (P3HT) film with a 2.5 nm-thick layer exhibits a higher mobility of 5.0×10−2 cm2/V·s than its bulk counterpart. The crystalline structure of the as-fabricated ultrathin P3HT layer is verified by atomic force microscopy as well as grazing incidence X-ray diffraction. Transient measurements of the as-fabricated transistors reveal the influence of the interface traps on charge transport. These results are explained by the trap energy level distribution at the interface manipulated by layers of polymer film. [ABSTRACT FROM AUTHOR]

Efficient heterojunction organic photovoltaic (OPV) cells are fabricated based on copper tetra-methyl phthalocyanine (CuMePc) as donor and fullerene (C60) as acceptor. The power conversion efficiency of CuMePc/C60 OPV cell (2.52%) is increased by 88% compared with that of the non-peripheral substituted copper phthalocyanine (CuPc)/C60 OPV cell (1.34%). The introduction of methyl substituent leads to stronger π—π interaction of CuMePc (∼ 3.5 Å) than that of CuPc (∼ 3.8 Å). The efficiency improvement is attributed to the enhanced carrier mobility of CuMePc thin film (1.1 × 10−3 cm2/V·s) and better film morphology by introducing methyl groups into the periphery of CuPc molecule. [ABSTRACT FROM AUTHOR]

The performance of organic field-effect transistor (OFET) memory devices with different size of gold nanoparticles (Au NPs) as charge trapping layers has been investigated. We synthesized 15 nm, 20 nm and 25 nm of Au NPs through a citrate-reduction method and 3-aminopropyltriethoxysilane (APTES) functionalized substrates were used to form a monolayer of Au NPs. In the programming/erasing operation, we observed reversible threshold voltage (Vth) shifts and reliable memory performances. A strong size-dependent effect on Vthshifts and memory effect was observed. Effect of size dependence on the mobilities (μ), on/off current ratios, subthreshold swings (S), data retention characteristics (>105s) and endurance performances operation (>800 cycles) of memory devices are discussed. The experimental results suggest a guideline for optimizing the size and density of Au NPs and their influence on the device properties. [ABSTRACT FROM AUTHOR]

A systematic experimental investigation to determine the shear, tensile, and fracture properties of adhesive joints with bonded same-materials (polymer-polymer) and bi-materials (metal-polymer) is reported. Full-field optical techniques including photoelasticity and coherent gradient sensing (CGS) are employed to record the stress development and failure in these adhesive joints. Five types of strong and weak adhesives are used in conjunction with five different types of materials [aluminum, steel, polymethylmethacrylate (PMMA), polycarbonate, and Homalite®-100] to produce a variety of bonded material systems. Weld-on®-10 and a polyester bonding consistently show higher tensile and shear bonding strengths. Bi-material systems in shear and fracture report lower properties than the same-material systems due to a higher property mismatch in the former. The resulting complete experimental data are expected to be immensely helpful to computational mechanists in simulating failure mechanics of adhesive joints. [ABSTRACT FROM AUTHOR]

Liquid crystal based sulfonic acid, 4-(octadecyloxy)phenylsulfonic acid, 1, effectively transports protons at 80 °C under non-humidified conditions. At its smectic Aliquid crystal state, the proton conductivity of 1was measured to be 1.1 × 10−2S cm−1. The proton conductivities of 1at its molten and solid powder states were found to be 1.2 × 10−4and 1.5 × 10−7S cm−1, respectively. A lamellar structure of bilayer stacks of 1with the sulfonic acid groups in a head-to-head configuration was found within the monodomain of SmAphase of 1from in situXRD and DFT calculation. We proposed that the efficient proton transporting property of 1is highly correlated to the formation of supramolecular pathways between the molecules at its liquid crystal phase. [ABSTRACT FROM AUTHOR]

Charged cationic cyclometalated iridium(iii) polypyridine complexes were electrostatically aligned and we found a regular packing of molecules with enhanced carrier mobility. [ABSTRACT FROM AUTHOR]

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Wood duck (Aix sponsa) hens are known to lay eggs in nests of other wood ducks. Low levels of intraspecific nest parasitism can increase the number of ducklings produced, but at high levels, increased numbers of eggs are offset by reduced hatching success and elevated nest abandonment. Such effects have been observed in nest boxes, stimulating interest in the role of intraspecific nest parasitism in natural cavities. We found high rates of nest parasitism (85% of nests) in natural cavities by applying microsatellite genetic markers to examine maternity for clutches laid in floodplain and upland forests. Clutch sizes, number of parasites per nest, and the number of parasitic eggs deposited per nest were greater in tree cavities located in floodplain than in upland forests (35.2%, 83.6%, 75.0% greater, respectively; P < 0.05), although the proportions of nests parasitized were similar (100% of floodplain nests versus 80% of upland nests, P = 0.11). We compared our data to almost 40 years of published data from studies of wood ducks using artificial nest boxes. Clutch sizes in natural cavities were smaller than reported for 3 populations using nest boxes (10.3%, 29.4%, and 49.2% smaller; P < 0.05), except when only floodplain nests were considered (5.0% larger, 11.6% and 28.8% smaller, P > 0.05). Fewer parasites (1.5 ± 0.1 parasites) contributed to nests in tree cavities than in 1 box-nesting population (2.7 ± 0.04, P < 0.05). We suggest that the high parasitism rates observed in natural cavities reflect the accuracy of microsatellite techniques relative to other methods and that conspecific nest parasitism is pervasive among wood ducks, even in natural tree cavities that are more widely dispersed and well hidden than nest boxes. However, despite the large proportion of cavity nests parasitized during this study, parasitism did not severely depress breeding productivity, as observed in some box-nesting populations. Long-term and experimental research on factors contributing to extremely large clutches in nest boxes could improve the efficacy of nest-box programs. [ABSTRACT FROM AUTHOR]

A systematic experimental investigation of the generation and subsequent evolution of impact damage in heterogeneous two-layer materials is presented. Model layered specimens involving a compliant polymer layer bonded with a metal layer were designed and subjected to impact loading to simulate failure mechanisms in real time. High-speed photography and dynamic photoelasticity were utilized to visualize the nature and sequence of dynamic failure modes. A series of complex failure modes was documented. Interlayer crack growth (interfacial delamination) is the dominant dynamic failure mode. These cracks appear to be shear dominated and might proceed with intersonic speeds. Intralayer cracking always occurs in a local Mode I crack inside the weak layer. Both impact speed and interfacial bonding strength have significant influence on the impact failure. High-impact loading leads to high interlayer crack speeds. Specimens featuring ductile and weak bonds subjected to high-impact speeds are shown to feature intersonic cracks with clearly visible shear shock wave (Mach lines) emitted from the crack tips. [ABSTRACT FROM AUTHOR]

A comprehensive investigation of the fiber pushout test reveals that the existence of free-edge stress singularities hinder the accurate measurement of interfacial shear strengths. An integrated analytical, numerical, and experimental investigation is conducted to remove the free-edge stress singularities by modifying the edge design in a model fiber pushout test. The proposed interfacial joint angles are applicable to most composite material systems. The microdroplet test is recommended over the fiber pushout test since the convex shape of the microdroplet matrix makes it a natural choice. [ABSTRACT FROM AUTHOR]

Mechanical property characterization including bending, tensile, and fracture properties for a new functionalized nanofiber/epoxy composite were conducted. Results show that there was only very little increase in mechanical properties of nanocomposites although we used GCNF-ODA reactive linkers to improve the interface. The interfacial stress level of nanocomposites should be much higher than that of traditional composites because of high property mismatch between the nanoscale reinforcement and the matrix. In order to design strong and stiff nanocomposite materials, one should use aligned nanofibers with a relatively large volume or weight fraction. Also, the length of the nanofiber should be long enough and its diameter not very small in order to facilitate the interfacial load transfer mechanism. [ABSTRACT FROM AUTHOR]

Examines subsistence affluence and market economy in Papua New Guinea. Identification of hybrid types of economic activities in the transition from subsistence to a market economy; Features of the traditional agriculture of the country; Formulation of a model abstracted from agriculture.

V. K. Ramaswami has recently shown that "when national income, inclusive of income earned abroad by factors of domestic origin, is to be maximized, optimal taxation of the import of the scarce factor is preferable to optimal restriction of the export of the abundant factor.''[2] The two-fold purpose of this note is to make explicit the general equilibrium analysis underlying Ramaswami's proposition, and to show that, while his policy recommendation is appropriate when a government is comparing the merits of acting as a monopolistic seller or monopsonistic buyer of factor services (a "one-versus-many" situation), it will not be the best policy where governments face each other in a bilateral bargaining situation. I do not refer here to the possibility of retaliatory action as that is understood in the literature on optimal tariffs--we shall follow Ramaswami in assuming no retaliation. The possibility to be discussed is one which, by analogy with ordinary monopoly analysis, arises when an "all-or-nothing" deal, as distinct from the conventional monopoly solution given by Ramaswami's formulae, is possible.[3]. [ABSTRACT FROM AUTHOR]

Focuses on the contributions of writer C.K. Hobson on economic literature. Effect of foreign investment on the economy of capital-exporting country; Analysis of partial equilibrium diagram developed by Hobson; Comparison of Hobson's diagram with the diagram used by writer MacDougall; Influence of capital export on domestic product.

While there has been much discussion of the relationship between the flexibility of the general price level and the level of activity, the relationship between variations in relative commodity prices and activity levels has received little attention in macroeconomic models, with the notable exception of two-sector growth models, as of May 1968. There is no doubt that there are many propositions about employment theory and policy for which this neglect of value theory in macro-models is of no consequence. However, the phenomenon now usually described in terms of the "Phillips curve" emphasizes that the structural characteristics of an economy have important implications for macroeconomic policy. Conventional macroeconomic models are not equipped to handle these problems since they are almost always designed with the simplest type of structure on the supply side. They generally postulate that all the needs of the economy may be met by one versatile commodity which may either be consumed or invested.

An unprecedented 2-D Cu–S network is constructed by self-assembly coordination between Cu(i) and 4-hydroxythiophenol and its structure was determined by using powder X-ray diffraction data. The self-assembled coordination network displays ionic behavior with a bulk electrical conductivity value of 120 S cm−1. [ABSTRACT FROM AUTHOR]

Discusses lessons pediatricians must learn and transmit on stresses facing the family in the 1970s. Conditions that may compromise mental health; Call for a reeducation on how to deal with family problems and their effects on children; Role of pediatricians in assisting parents toward developing better parent-child communication and in educating them to provide more appropriate child rearing.

Centaurus A (Cen A) is a bright radio source associated with the nearby galaxy NGC 5128 where high-resolution radio observations can probe the jet at scales of less than a light day. The South Pole Telescope (SPT) and the Atacama Pathfinder Experiment performed a single-baseline very-long-baseline interferometry (VLBI) observation of Cen A in 2015 January as part of VLBI receiver deployment for the SPT. We measure the correlated flux density of Cen A at a wavelength of 1.4 mm on a ∼7000 km (5 Gλ) baseline. Ascribing this correlated flux density to the core, and with the use of a contemporaneous short-baseline flux density from a Submillimeter Array observation, we infer a core brightness temperature of 1.4 × 1011 K. This is close to the equipartition brightness temperature, where the magnetic and relativistic particle energy densities are equal. Under the assumption of a circular Gaussian core component, we derive an upper limit to the core size ϕ = 34.0 ± 1.8 μas, corresponding to 120 Schwarzschild radii for a black hole mass of 5.5 × 107M⊙. [ABSTRACT FROM AUTHOR]

We report results from very long baseline interferometric (VLBI) observations of the supermassive black hole in the Galactic center, Sgr A*, at 1.3 mm (230 GHz). The observations were performed in 2013 March using six VLBI stations in Hawaii, California, Arizona, and Chile. Compared to earlier observations, the addition of the APEX telescope in Chile almost doubles the longest baseline length in the array, provides additional uv coverage in the N–S direction, and leads to a spatial resolution of ∼30 μas (∼3 Schwarzschild radii) for Sgr A*. The source is detected even at the longest baselines with visibility amplitudes of ∼4%–13% of the total flux density. We argue that such flux densities cannot result from interstellar refractive scattering alone, but indicate the presence of compact intrinsic source structure on scales of ∼3 Schwarzschild radii. The measured nonzero closure phases rule out point-symmetric emission. We discuss our results in the context of simple geometric models that capture the basic characteristics and brightness distributions of disk- and jet-dominated models and show that both can reproduce the observed data. Common to these models are the brightness asymmetry, the orientation, and characteristic sizes, which are comparable to the expected size of the black hole shadow. Future 1.3 mm VLBI observations with an expanded array and better sensitivity will allow more detailed imaging of the horizon-scale structure and bear the potential for a deep insight into the physical processes at the black hole boundary. [ABSTRACT FROM AUTHOR]

An initial three-station version of the Event Horizon Telescope, a millimeter-wavelength very-long baseline interferometer, has observed Sagittarius A* (Sgr A*) repeatedly from 2007 to 2013, resulting in the measurement of a variety of interferometric quantities. Of particular importance is that there is now a large set of closure phases measured over a number of independent observing epochs. We analyze these observations within the context of a realization of semi-analytic radiatively inefficient disk models, implicated by the low luminosity of Sgr A*. We find a broad consistency among the various observing epochs and between different interferometric data types, with the latter providing significant support for this class of model of Sgr A*. The new data significantly tighten existing constraints on the spin magnitude and its orientation within this model context, finding a spin magnitude of , an inclination with respect to the line of sight of , and a position angle of east of north. These are in good agreement with previous analyses. Notably, the previous 180° degeneracy in the position angle has now been conclusively broken by the inclusion of the closure-phase measurements. A reflection degeneracy in the inclination remains, permitting two localizations of the spin vector orientation, one of which is in agreement with the orbital angular momentum of the infrared gas cloud G2 and the clockwise disk of young stars. This may support a relationship between Sgr A*'s accretion flow and these larger-scale features. [ABSTRACT FROM AUTHOR]

Reviews the computer software U&I/Arboretum Systems MetaSynth for Mac OS.

Comments on the paper 'Development of Trade Practices Law and Administration,' by R.M. Bannerman, discussing commercial policy-making in Australia. Content of economics courses; Simplified approach to competition policy in many basic economic courses; Economic conditions having a profound effect on the development of competition law and administration in the country.