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Threats to endangered insect species that act independently of those associated with habitat loss are often suspected, but are rarely confirmed or quantified. This may hinder the development of the most effective recovery strategies, which are increasingly needed for listed insects. Since 2006, 14 species of flies within the large, showy Hawaiian picture-winged Drosophila group have been added to the US threatened and endangered species list. Many of these species are thought to be limited by host plant rarity, but also by predation on immature stages by invasive ants. We tested the latter hypothesis with a field experiment involving Drosophila crucigera, a more common surrogate for sympatric endangered species, and the invasive ant Solenopsis papuana, on the island of Oʻahu. We established ant suppression and control plots across three forest sites. Within each plot we placed a host plant branch piece, into which lab-reared flies had oviposited, and subsequently tracked weekly emergence of adults. Numbers of flies that emerged were 2.4 times higher in ant-suppressed plots than in control plots; this 58% reduction in survival from egg to adult in the presence of ants was similar across all three sites. Among plots, numbers of emerged flies exhibited a pattern suggesting that the detrimental effect of ants is density dependent. These results confirm that S. papuana, and possibly other invasive ant species, can strongly impact the reproductive success of Hawaiian picture-winged Drosophila. They also point to several management actions, beyond habitat restoration, that may improve the recovery of these imperiled flies.

Because of the essential role of minerals in maintaining homeostasis in large herbivores, a dietary intake that avoids deficiency or excess is crucial to keeping animals healthy. However, mineral element concentrations are highly variable between and within plant species. We therefore hypothesized that the mineral balance in grazing cattle may be influenced by plant species abundance in pasture. We simulated mineral intakes using two different models (algorithms) for varying numbers of 17 plant species characterized in a field survey of a temperate pasture in Japan. We calculated the mineral intakes from 1000 combinations of species for each species richness (number of species) for each of 12 mineral elements. Both models indicated that the estimated intakes of Mg, K and Mn could exceed the maximum tolerable range, and those of P, Na, Fe and Cu could potentially fail to meet the minimum requirements. The mean proportion of estimated intakes that ranged between minimum requirement and maximum tolerable level was approximately 17% higher for 17 species than for a single species. These results suggest that increasing the plant diversity in the pasture reduced the risk of mineral deficiencies or toxicities. Our results indicate that wild plants, normally regarded as weeds, should be maintained within improved pasture to maintain species diversity and assist with the mineral balance of animals grazed upon it. This work is an important precursor to future studies linking animal husbandry and ecological research.

We have investigated the relation among ρ – T characteristics, superconductivity, annealing conditions and the crystallinity of polycrystalline (In 2 O 3 ) 1− x –(ZnO) x films. We annealed as-grown amorphous films in air by changing annealing temperature and time. It is found that the films annealed at 200 °C or 300 °C for a time over 0.5 h shows the superconductivity. Transition temperature T c and the carrier density n are T c n ≈ 10 25 –10 26 m −3 , respectively. Investigations for films with x = 0.01 annealed at 200 °C have revealed that the T c , n and crystallinity depend systematically on annealing time. Further, we consider that there is a suitable annealing time for sharp resistive transition because the transition width becomes wider with longer annealing times. We studied the upper critical magnetic field H c2 ( T ) for the film with different annealing time. From the slope of dH c2 / dT for all films, we have obtained the resistivity ρ dependence of the coherence length ξ (0) at T = 0 K.

A micro-beam NRA system, by means of a resonant nuclear reaction 1H(15N, αγ)12C, has been developed for the purpose of the 3D mapping of the hydrogen distribution in solids. To obtain the tens μm size of the beam spot, the combination of the newly proposed tapered glass capillary and a conventional quadrupole magnetic lens is employed. An Y patterned film on a substrate is prepared as an application of the developed system. The 6 MeV 15N beam focused by glass capillaries down to 50 μm successfully shows the hydrogen distribution. The in-plane NRA profile implies that the beam emitted from the glass capillary outlet is parallel, although the original beam has a considerable divergence. The NRA measurements in the 103 Pa N2 atmosphere due to the low gas conductance of the glass capillary is also demonstrated.

Hydrogen adsorbed on the Pt(1 1 1)–Sn surface alloys was investigated by nuclear reaction analysis (NRA) using 1H(15N,αγ)12C. The γ-ray intensity profile as a function of the incident ion energy is analyzed on the basis of the Doppler broadening. From the widths of the resonance profiles, the zero-point vibrational energies in the vertical and in-plane directions are estimated to be 78.2 ± 3.7 and 53.6 ± 5.8 meV on Pt(1 1 1)2 × 2–Sn, respectively, and 72.5 ± 3.7 and 58.5 ± 6.7 meV on Pt(1 1 1)√3 × √3–Sn, respectively. The adsorption state and vibrational property of H on the surface alloys are discussed.

We report experimental results on the interaction of hydrogen with monolayer thin Ag and Au films grown on a Pt(1 1 1) substrate, measured with thermal desorption spectroscopy (TDS) and nuclear reaction analysis (NRA). We found that H2 dissociative adsorption is activated on both thin film surfaces. Atomic hydrogen was found to adsorb on the Ag and Au films on Pt(1 1 1) with main desorption temperatures of 160 and 120 K, respectively. The monolayer thin Ag and Au films on Pt(1 1 1) are chemically similar to the (1 1 1) surfaces of bulk Ag and Au, respectively.

To improve overcoat films for giant magnetoresistive (GMR) heads, we developed a commercial multi-film deposition system capable of performing three diamond-like carbon (DLC) deposition methods, i.e. electron cyclotron resonance-chemical vapor deposition (ECR-CVD), ion beam deposition (IBD), and filtered cathodic vacuum arc (FCVA); pre-cleaning with Ar sputtering etch; and Si adhesion layer deposition. In comparative evaluations of 50-nm-thick films deposited on a Si wafer, ta-C film by FCVA shows higher hardness/density compared to DLC films by ECR-CVD or IBD. Scratch testing and electron spectroscopy for chemical analysis (ESCA) measurements of films prepared by ECR-CVD and FCVA on an Al 2 O 3 TiC substrate indicate that substrate bias enhances mixing between the carbon film and either the Si film or Al 2 O 3 TiC substrate such that good adhesion occurs.

We performed direct measurement of hydrogen content in diamond-like carbon (DLC) thin films using elastic recoil detection analysis (ERDA) of hydrogen atoms forward-scattered by a 2 keV beam of helium ions. DLC films were prepared in an electron cyclotron resonance (ECR) microwave plasma chemical vapor deposition (CVD) system. Use of a low-energy beam in conjunction with a small incidence angle allowed measurements of hydrogen content in the surface region of films of various thickness (2.4, 5 and 100 nm). Analysis of resultant spectra indicates that a higher negative substrate bias voltage produces lower hydrogen content; these findings are consistent with those obtained on thick DLC films using high-energy (2–3 MeV) ERDA. Accordingly, this confirms the suitability of using the low-energy ERDA system described to measure hydrogen content in ultrathin (

A tracer study was performed to assign a radical produced with UV irradiation on photocatalytically active BaTi 4 O 9 for water decomposition. BaTi 4 O 9 was reduced in H 2 and oxidized in 16 O 2 , 17 O 2 or 18 O 2 at different temperatures. The behavior of oxygen exchange was investigated by thermal gravimetric analysis and Raman spectroscopy. Electron magnetic resonance spectra showed that new signals with g ⊥ =2.038 and g ⊥ =2.026 due to hyperfine splitting of 17 O − with A ⊥ =19.1 G appeared when oxidized in 17 O 2 , in addition to normal signals with g ⊥ =2.018 and g ‖ =2.004. The radical is assigned to O − produced from surface lattice oxygen of BaTi 4 O 9 .

The UV irradiation of barium tetratitanate, BaTi 4 O 9 , with a unique pentagonal-prism tunnel structure, produced an EPR signal with g =2.018 and g =2.004 at 77 K: the signal had a short lifetime in vacuum, whereas it was stable in the presence of gaseous molecules (O 2 , H 2 , He, Ar) independently of the kinds of gases. The radical reacted with gaseous oxygen and formed O 3 − at room temperature. The species is assigned to an O − radical resulting from lattice oxygen at the surface, and its formation is closely related to the distorted TiO 6 octahedra forming the tunnel.

The dissociation of some chlorofluoroethanes, CClF2CHCl2, CClF2CH2Cl, CCl2FCHCl2, and CCl2FCH2Cl, and bromofluoroethanes, CBrF2CHBrF, and CBrF2CH2Br etc. under the irradiation of TEA CO2 laser or vacuum ultraviolet (VUV), 147 nm, or by thermal heating was investigated through the analyses of the products by GC mass-spectrometry. The thermal and the laser dissociation of chlorofluoroethanes proceeded to form various ethenes through the dehydrochlorination, and in each case, a close similarity was found between the thermal and the laser dissociation behaviors. In the laser dissociation of CClF2CHCl2, and CClF2CH2Cl, a distinct wavelength dependence of the rate was observed, in each case, and a cause of the dependence seems to be due to the existence of the conformational isomers. In the cases of VUV irradiation of chlorofluoroethanes, they dissociated along with the concurrent elimination of Cl2 and HCl. In any case, the rate of Cl2 elimination was larger than the HCl elimination, and the Cl2/HBr ratio differed depending on the molecular form of the chlorofluoroethane. The laser dissociation of bromofluoroethanes mainly occurred with the elimination of Br2. However, both the elimination reactions of Br2 and HBr occurred concurrently in the thermal dissociation, where the occurrence of HBr elimination was much higher in all cases contrary to the laser dissociation. The mechanisms of these reaction behaviors will be discussed.

A deeper understanding of water sorption phenomena in MgF 2 films has been acquired by investigation of the substrate temperature dependence of the packing densities and the dynamic change in water sorption in the pores of the films through various subsequent treatments. As a result, 10% of the total volume of the films, or 32.0–35.7% of the total pores, has been shown to be already occupied by water molecules before the films are exposed to air. When this effect was taken into account the true value of the packing density of MgF 2 films deposited onto unheated substrates was found to be 0.72–0.75.

A new ultrasonic inspection system was developed to obtain ultrasonic images of defects. This system adopts an electronic beam control method using array transducers. The beam control modes are a compound scanning mode and a linear scanning mode. Both modes are performed by timing control of ultrasonic wave transmission and reception at each transducer element. In the focal beam, the refraction of the ultrasonic wave at the boundary between water and metal in immersion testing is utilized to improve the lateral resolution of the ultrasonic beam. In steel, the improvement is a maximum of 25% for focal lengths from 5 to 35 mm as compared to lateral resolution not utilizing refraction. This system successfully imaged two side drilled holes in a steel block.

A generalized second-best problem, involving a perfectly competitive industry which produces a pollution type of externality, is examined. The pollution tax is allowed to assume an arbitrary value (possibly zero), while a pollution standard, set as a ratio of pollution to output, is determined by a first-order optimizing condition. The general condition for a set of quasi-optimal solutions includes the Pareto-optimal solution as a special case. It is also found that when the pollution tax is below the optimal level, the usual implication is that the standard should be set so that the marginal cost of pollution reduction exceeds the marginal external damage.

The inhomogeneity of the refractive index in optical thin films has often been represented by an assembly of two homogeneous layers, one usually being rather thinner than the other and with a refractive index further removed from that of the ideal single layer. In this present study the inhomogeneity is related more directly to the physical structure of the layers and especially to the form of their columnar grains. In order to derive the optical properties of a columnar solid, techniques for the calculation of the refractive index of arrays of columns are necessary, and a number of possible techniques are compared. The inhomogeneity in films of zinc sulphide, cryolite and titanium dioxide is interpreted in terms of the columnar model of film structure and its relationship with other aspects, such as packing density, is examined.