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A special feeding technique of an off-centered microstrip feedline slot-coupled circularly polarized (CP) cylindrical dielectric resonator antenna (DRA) for 2.4-GHz industry, science and medicine (ISM) band applications is reported in this letter. Good CP characteristics can be achieved using two coupling points with a quarter-wavelength path difference and 90° phase shift, resulting in a series feeding circuitry. The 10-dB impedance bandwidth and the 3-dB axial ratio of the proposed antenna are 141 and 85 MHz, respectively. Details of the antenna design procedure are described and typical experimental results are presented and discussed.

Staphylococcal enterotoxins (SEs) are important causative agents in gastroenteritidis and food poisoning cases. They are serologically grouped into five major classical types, i.e., SEA, SEB, SEC, SED, and SEE. In addition, new SEs, such as SEG through SEM, have recently been identified and characterized. In an attempt to survey the distribution of classical and new SEs in organisms responsible for staphylococcal infections in Taiwan, we developed PCR primers for the genes that define the SEK, SEL, and SEM types. Bacterial strains other than sek, sel, and sem Staphylococcus aureus, including strains of other Staphylococcus species, did not generate any false-positive results when examined with these primers. The expression potential for the sek, sel, and sem types were also determined by reverse transcription-PCR. Together with the PCR primers specific for the classical SEs and other new SEs, including SEG, SEH, SEI, and SEJ, we surveyed the SE genes in S. aureus strains isolated from food poisoning cases. For 147 S. aureus isolates originating from food poisoning cases, 109 (74.1%) were positive for one or more SE genes. Of them, the major classical enterotoxin type was sea (28.6%), followed by seb (20.4%), sec (8.2%), and sed (2.0%). For the new SE types, sei (30.6%) was detected the most often, followed by sek (18.4%), sem (12.9%), and sel (8.2%). Also, 64 (43.5%) of the total bacterial strains had more than one enterotoxin gene.

The temperature and frequency dependences of the dielectric responses and the complex impedance spectra of polycrystalline CaCu 3 Ti 4 O 12 ͑CCTO͒ doped with CaSiO 3 have been investigated. The dielectric responses show two Maxwell-Wagner-type relaxations including insulating layers of grain boundaries and domain boundaries and semiconducting grains. The behavior of the temperature dependence of the dielectric constant at 1 kHz is demonstrated to be determined by the frequency dependence of the dielectric constant of two superposed dielectric relaxations at different temperatures. In contrast to the undoped CCTO, an extra semicircle clearly appears in the complex impedance plots of CaSiO 3 -doped CCTO. The results further confirm the presence of the domain boundaries, and their resistivity is lower than that of the grain boundaries. The microstructures have been characterized and the compositions of the grains, grain boundaries, and the second phases have been determined quantitatively. The Si ions are proved to be segregated to the grain boundaries. The grain-boundary phases consist of a main Si-rich amorphous phase and a small amount of nanosized Cu-rich particles. The Cu-rich particles are present at grain edges or corners of the microstructures. The variations of the electrical conduction and the dielectric responses are related to the reduction of the concentration of the excess Cu ions along the grain boundaries.

When ammonia is added in methane to form carbon films using thermal chemical vapor deposition, effects of the ammonia/methane ratio on the deposition rate and microstructures of carbon films are investigated. Meanwhile, effects of the deposition temperature, working pressure, and residence time on the deposition rate are also considered. Experimental results indicate that as the ammonia/methane rate increases, the deposition rate of carbon films decreases, and also, the ordered degree, nano-crystallite size, and sp2 carbon atoms of carbon films increase. Nevertheless, if the deposition temperature, working pressure, and residence time increase, the deposition rate of carbon films increases. The relationship between the deposition rate and deposition process parameters is formulated. The deposition process is controlled by the process to create mono-carbon and bi-carbon species in carbon films. Moreover, one mono-nitrogen will suppress about three mono-carbons to form carbon films. Few nitrogen and hydrogen atoms are incorporated into carbon films. The activation energy (507 kJ/mole) of carbon deposition is related to the activation energies of methane and ammonia dissociation. If the working pressure is smaller than a threshold value (30 kPa) or the residence time is shorter than a threshold value (1.5 s), no film is formed

An efficient protocol for the Agrobacterium tumefaciens-mediated transformation of calla lily (Zantedeschia elliottiana (W. Wats.) Engl. cultivar 'Florex Gold') is described. Shoot basal discs were co-cultivated with A. tumefaciens C58C1 carrying a plasmid containing neomycin phosphotransferase (nptII) and plant ferredoxin-like protein (pflp) genes. After Agrobacterium co-cultivation, the shoot basal discs were exposed to 100 mg l(-1) kanamycin for selection. Twenty-eight out of 260 discs (10.8%) were found to have survived and produced shoot clusters. Twenty-six of these were confirmed to contain the pflp transgene by PCR, ending up in 10% transformation efficiency. The disease resistance investigation revealed that 18 transgenic plants exhibited resistance to soft rot disease caused by Erwinia carotovora subsp. carotovora. The presence of pflp gene was demonstrated by PCR, and its accumulation and activity was confirmed by Western blot and disease resistance assay. This was the first report to show the successful transformation and resistance to a bacterial pathogen in Zantedeschia. The protocol is useful for the quality improvement of calla lily through genetic transformation.

The effects of ultraviolet (UV)-ozone treatment on solution-processed amorphous InGaZnO (IGZO) thin-film transistors (TFTs) grown using the sol-gel method are investigated. The UV-ozone-treated TFT devices showed an improved field-effect mobility of 1.52 cm V s and a subthreshold slope (S) of 0.42 V/dec compared to those of IGZO TFT devices with only thermal annealing (0.75 cm V s and 0.84 V/dec, respectively). The enhancement of the UV-ozone-treated TFTs is mostly attributed to the increased film packing density, higher Al S/D electrodes adhesion properties, reduced oxygen-related defects, and less electron trapping of the IGZO thin films, which improved the TFT performance and bias stress stability.Index Terms-Amorphous InGaZnO (IGZO), sol-gel, ultraviolet (UV)-ozone.

Previous studies have reported substantial improvement of microbubble (MB)-mediated drug delivery with ultrasound when drugs are loaded onto the MB shell compared with a physical mixture. However, drug loading may affect shell properties that determine the acoustic responsiveness of MBs, producing unpredictable outcomes. The aim of this study is to reveal how the surface loaded drug (doxorubicin, DOX) affects the acoustic properties of MBs. A suitable formulation of MBs for DOX loading was first identified by regulating the proportion of two lipid materials (1,2-distearoyl-sn-glycero-3-phosphocholine (DSPC) and 1,2-distearoyl-sn-glycero-3-phospho-rac-glycerol sodium salt (DSPG)) with distinct electrostatic properties. We found that the DOX loading capacity of MBs was determined by the proportion of DSPG, since there was an electrostatic interaction with DOX. The DOX payload reduced the lipid fluidity of MBs, although this effect was dependent on the spatial uniformity of DOX on the MB shell surface. Loading DOX onto MBs enhanced acoustic stability 1.5-fold, decreased the resonance frequency from 12–14 MHz to 5–7 MHz, and reduced stable cavitation dose by 1.5-fold, but did not affect the stable cavitation threshold (300 kPa). Our study demonstrated that the DOX reduces lipid fluidity and decreases the elasticity of the MB shell, thereby influencing the acoustic properties of MBs.