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Airborne insect particles have been identified as an important cause of respiratory allergies, including allergic asthma and rhinitis. In the literature, the significance of respiratory exposure to insect particles as a cause of occupational allergy has been well-documented. Indeed, many cases of occupational allergy have been reported including allergy to the larvae of flies and moths in anglers and occupationally exposed workers, to grain pests in bakers or other workers handling grains, and to crickets and/or locusts in researchers and workers in aquaculture companies. Furthermore, the prevalence of sensitization to insect allergens is considerably high among patients with asthma and/or rhinitis who are not occupationally exposed to insects, suggesting the clinical relevance of exposure to insects in indoor and outdoor environmental non-occupational settings. Exposure to cockroaches, a well-studied indoor insect, is associated with cockroach sensitization and the development and exacerbation of asthma. Booklice, another common indoor insect, were recently identified as a significant sensitizer of asthmatic patients in Japan and India, and potentially of asthma patients living in warm and humid climates around the world. Lip b 1 was identified as an allergenic protein contributing to the species-specific sensitization to booklice. Moths are considered a significant seasonal outdoor allergen and their allergens are considered to have the highest sensitization rate among Japanese patients. However, other than cockroaches, allergenic insect proteins contributing to sensitization have not been fully characterized to date.

Household air conditioners are known to be contaminated with dematiaceous fungi such as genus Toxicocladosporium and genus Cladosporium. We frequently encounter cases in which a large amount of fungi, which are presumed to belong to the family Cordycipitaceae, are isolated from the blowout air of the household air conditioners. Therefore, the Cordycipitaceae isolated in the survey of four cases of the air conditioners were identified by genetic analyses. As a result, all of them were found to be Simplicillium sympodiophorum. The concentration of airborne fungi, S. sympodiophorum in the blowout air was high (> 104 cfu/m3) as exceeding the upper limit of quantification in three of four cases, and 5,000 cfu/m3 in one case. This study revealed that S. sympodiophorum contaminated multiple air conditioners. Genus Toxicocladosporium was also isolated from the two air conditioners, and it was found to be Toxicocladosporium irritans by the genetic analysis.

Objectives Consistently variable with several peaks in heart rate histogram (e.g. bigeminy and trigeminy) is one of the arrhythmia types. We investigated the effects of gating error by consistently variable patients on left ventricular (LV) functional with cadmium zinc telluride (CZT) camera. The purpose of this study is to evaluate LV functional parameters by setting different heartbeat acceptance windows on gated myocardial perfusion single-photon emission computed tomography (SPECT) (MPS) in consistently variable patients, using echocardiography (echo) as a reference. Materials and methods Sixteen consistently variable patients underwent the gated MPS using a D-SPECT. The MPS images were obtained by setting two different types of heartbeat acceptance windows. The heartbeat acceptance windows were set to include only one peak and two peaks of the maximum count peaks, respectively. Results Mean end-diastolic volume, end-systolic volume and left ventricular ejection fraction (LVEF) were 112.7 mL, 62.2 mL and 51.3% for one peak, 114.5 mL, 66.1 mL and 47.1% for two peak, and 113.0 mL, 54.2 mL and 54.1% for echo, respectively. The mean differences between two peaks and echo in LVEF were larger than those of between one peak and echo. Conclusion Our study suggests that setting the heartbeat acceptance window of one peak was suitable for accurate measurement of LV function in consistently variable patients.

A 43-year-old woman presented with oral discomfort, sneezing, urticaria, eyelid angioedema, abdominal pain, diarrhoea, dyspnoea and wheeze soon after eating a Japanese flour pancake (okonomiyaki, containing wheat, egg, yam, pork, prawn and squid). Subsequent analysis of the flour used in the pancake revealed the presence of Dermatophagoides farinae (4500 mites/g). The patient tested positive for specific IgE to D. farinae (15.2 kU/L) and D. pteronyssinus (14.0 kU/L) with negative responses to other ingredients in the pancake. Oral ingestion of dust mite in poorly stored foods can cause anaphylactic reactions in patients with allergy.

This paper describes that the probabilities of exceedance is so effective to estimate safe and secure structural parameters under considering the incompatibility between the seismic performance and the wind-resistance performance. In this paper, a technique, which estimate the comprehensive safety for the earthquake loading and the wind loading based on the concept of probability, is indicated. It is tried that the structural parameters of base-isolated high-rise buildings are estimated by means of this technique. From the results, it is confirmed by estimating the probabilities of exceedance that the seismic performance and the wind-resistance performance have the incompatibility. It is also confirmed that the displacement in the base-isolator and the shear force in the first story have the incompatibility. The possibility to estimate safe and secure structural parameters for the design criteria based on the probability concept is indicated.

This work is concerned with the proposition of high contrast multi-layer structure for the fabrication of reflecting surface in the visible range. The multi-layer SiO2/Ta2O5 system has superior heat resistance and reflecting properties. Ta2O5 and SiO2 thin films were prepared by RF plasma sputtering in Ar-O2 mixed gas using Ta2O5 and SiO2 target respectively. Secondary ion mass spectroscopy and SEM observation were performed in order to investigate the multi-layer structure. The XRD and XPS analyses were also performed in order to investigate the crystal structure and the chemical state of the films. The optical constants of Ta2O5 single film were investigated by the ellipsometric analysis. Using the Ta2O5 film doped Bi2O3 for a reflecting multi-layer structure improved the reflecting properties and the heat resistance of the multi-layer system because of the high refractive index of the doped film.

Nanosecond pulsed-Nd:YAG laser irradiation of a target material with second-harmonic waves (wavelength=532 nm) under various gas atmospheres resulted in the formation of tungsten microcone arrays with a high aspect ratio protruding from the initial surface of the target material. The peak laser fluence was changed from 3.0 to 19.1 J/cm2. A tungsten substrate was irradiated with between 1 and 48 000 laser shots. The number of laser shots strongly influenced the growth and morphology of the microcones: several tens or hundreds of pulses created only rough surfaces, and further pulses created the microcones. The microcones grew to heights of up to 20 μm and narrowed to tips of about 1.5 μm in diameter. Our observations reveal that tungsten microcone can be generated in various ambient gases. We experimentally evaluated the microcone morphology in order to determine the mechanism of microcone formation in ambient atmospheres of helium, SF6, and air. The microcone formation appears to be a function of the repeated melting and solidification of the tungsten tips of the structures by the pulsed laser irradiation on the top surface. The morphology of the microcone depends on the ambient gas atmosphere used.

Gold nanoparticles have great potential for various nanoelectronic applications such as single electron transistors, an infrared absorption sensor and so on. It is very important to understand and control the size distribution of the particles for such a variety of applications. In this paper, we report the size distribution of gold nanoparticles and the relationship between the nanoparticle-films and the electrical property produced by a laser ablation method. Gold nanoparticle-films were prepared by a technique, which sprays nanoparticles on the substrate through a nozzle. We call it a gas deposition method. The nanoparticles were generated by the nanosecond pulsed Nd:YAG laser ablation of a gold substrate under a low-pressure inert gas atmosphere. The ambient pressure was changed to control the average size and their distribution. The particles produced in the generation chamber were transported by a helium carrier gas to the deposition chamber and deposited on a substrate to form the films composed of gold nanoparticles. The electrical resistivity of the generated gold nanoparticle-films on the glass substrates was measured using a four-probe method. The size distribution of the nanoparticles was examined using transmission electron microscopy (TEM) and a low-pressure differential mobility analyzer (LP-DMA). The relationship between the particle size and the electrical properties of each film made by the different synthesis conditions were analyzed. The electrical resistivity changed from the order of 10 −5 to 10 −1 Ω cm depending on the ambient pressure and the size distribution.

Uniform silicon single nanodots were synthesized by laser ablation with a differential mobility analyzer (DMA) technique. The Si nanoparticles generated by laser irradiation of a silicon target were actively classified by a DMA and were impacted on the solid surface by a “nanoparticle beam”. By measuring the current of the beam, we determined the size distribution of generated particles in situ. From transmission electron microscope (TEM) observation of deposited dots, it was found that they were well-isolated and uniform in size. High-resolution TEM images indicated that they were single crystals with a diameter of 10, 7, and 5 nm. However, the particles less than 4 nm seemed to have no crystallinity (amorphous).

Nanometer-sized particles of silicon and titanium oxide were generated by irradiating solid targets using a nanosecond pulsed-Nd : YAG laser in a low pressure atmosphere. A low pressure differential mobility analyzer (LP-DMA) was used to classify the size of the generated particles. The LP-DMA and electron microscopes (SEM and TEM) were used to measure the change in the size distribution and morphology of the generated particles with laser power density and system pressure. The size distribution of both silicon and titanium oxide ranged from two to one hundred nanometers in diameter depending on the laser power density and pressure. From the high resolution TEM observation and electron diffraction, it was found that the generated titanium oxide nanoparticles were composed of a ‘core’ of faceted metallic single crystals with an oxide layer 'shell’.

We found a coherent array of tungsten ultrafine particles of about 700 nm around a laser-irradiated mark on a single-crystalline surface of tungsten. The tungsten specimens were irradiated by a short-pulse Nd:YAG laser under low pressure in an inert gas atmosphere. Two types of coherent arrays were observed that included the two-dimensional cubic and hexagonal systems. Such a coherent array of ultrafine particles may have potential applications for emission devices of plasma display and microelectronic devices.

Potential-induced degradation (PID) of Cu(In,Ga)Se_2 (CIGS) photovoltaic (PV) modules fabricated from integrated submodules is investigated. PID tests were performed by applying a voltage of −1000 V to connected submodule interconnector ribbons at 85 °C. The normalized energy conversion efficiency of a standard module decreases to 0.2 after the PID test for 14 days. This reveals that CIGS modules suffer PID under this experimental condition. In contrast, a module with non-alkali glass shows no degradation, which implies that the degradation occurs owing to alkali metal ions, e.g., Na^+, migrating from the cover glass. The results of dynamic secondary ion mass spectrometry show Na accumulation in the n-ZnO transparent conductive oxide layer of the degraded module. A CIGS PV module with an ionomer (IO) encapsulant instead of a copolymer of ethylene and vinyl acetate shows no degradation. This reveals that the IO encapsulant can prevent PID of CIGS modules. A degraded module can recover from its performance losses by applying +1000 V to connected submodule interconnector ribbons from an Al plate placed on the test module.

Metal nanoparticles films were prepared by a gas deposition technique couple with the nanosecond pulsed Nd:YAG laser ablation of two kinds of metal targets. Two generated nanoparticles were insitu mixed in the near space of the targets in the generation chamber and transported by a helium carrier gas to the deposition chamber and deposited on a substrate to form electric devices such as a resistor, a capacitor, wiring, etc., composed of nanoparticles composites. The electrical resistivity and capacity of the devices were measured. The relationship between the experimental conditions such as ambient pressure and laser fluences and the electrical properties of each device were analyzed. A heater was produced as an example of the application of a resistor.

We have discovered coherent arrays of ultrafine particles around a laser-irradiated mark. We tried to apply these arrays for electron emission guns. However, it was not successful due to their low aspect ratio. We observed microcones, which were made in the laser-irradiated mark on the initial surface of the target material. They seem to have a higher aspect ratio than the coherent arrays because heavy irradiation was needed to obtain cones with a high aspect ratio. Therefore, we examined the tungsten microcone growth in various gas atmospheres. The experimental results indicated that tungsten microcone growth did not depend on the impurities in the gases. In this paper we experimentally show the morphologies of the microcone in order to understand the microcone formation mechanism in various ambient atmospheres such as helium, SF 6 , and air. The difference in the microcone formation mechanism among the tungsten and Si substrate is discussed as related to the VLS (vapor-liquid-solid) mechanism.

Tungsten microcone arrays with a high aspect ratio, which protrude from the initial surface of a target material, have been formed by Nd:YAG laser irradiation of tungsten in a low pressure inert gas atmosphere. The laser fluences were 1.5- 9.6 J/cm2 at SHG. The tungsten substrate was irradiated with 1-3600 pulses. The microcone growth was strongly affected by the number of laser pulses. The microcones were up to 20 micrometers tall and had about a 1.5 micrometers diameter at the tip. Several ten or several hundred pulses caused only a rough surface while subsequent pulses created the microcone arrays. Silicon, polymer, and oxides were used as the target materials in the former studies. The growth on these substrates could be attributed to the presence of various impurities and chemical gases. However, we used no impurities or chemical gases in this experiment. We believe that the growth mechanism of the microcones might be different from this study. It was concluded that the melted/solidification tungsten tip induced by the repetition of the pulsed laser irradiation on the top surface plays a significant role in the formation of the microcones. These tall tungsten microcone arrays might be very attractive for various industrial applications.© (2001) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.

A non-lithographic coherent array of ultrafine tungsten particles (150-500 nm diameter) is self-assembly arranged around a laser-irradiated mark on a tungsten substrate. Single and poly-crystal tungsten substrates were irradiated by a Q-switched Nd:YAG laser under low pressure in an inert gas atmosphere. We studied the effect of the laser fluence on the morphology of the coherent arrays. Scanning electron microscopy (SEM) and transmission electron microscopy (TEM) were used for these observations. The spacing of the coherent array increases with increasing laser fluence. For a 10.5 J/cm2 irradiation, many droplets and peeling of the surfaces induced by rapid thermal expansion of the tungsten surface were observed. The recrystallizatoin texture on the surface was also confirmed by TEM observations. This suggests that the irradiated surface layer was partially recrystallized during laser irradiation. We concluded that coherent arrays are related to the laser fluence, the crystal surface structure, and the crystal growth. The recrystallization of the slightly melted tungsten on the top surface induced by the repeated laser irradiation plays a vital role in the formation of the array. If we can produce a coherent array of ultrafine tungsten particles with a higher aspect ratio, it may have potential applications for the emission cathodes of field emission displays (FED) and microelectronic devices.© (2000) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.