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ABSTRACT In this article, a reconfigurable antenna for wireless wide area network (WWAN) mobile handset application is proposed. The proposed antenna consists of a conventional planar inverted-F antenna (PIFA), parasitic line, PIN diode, and bias line. The PIN diode is located between the parasitic line and ground, and its connection is electrically controlled by the on/off state of the PIN diode. The antenna's wide low band is formed by switching the quarter-wavelength resonance mode of a conventional PIFA and covers the GSM850/900 bands. The antenna's high band is formed by the harmonic mode of a conventional PIFA and a new generated loop mode and covers the GSM1800/1900/UMTS bands. A stable and omnidirectional radiation pattern with a reasonable gain is observed over the operating bandwidth. © 2014 Wiley Periodicals, Inc. Microwave Opt Technol Lett 56:2888-2893, 2014 [ABSTRACT FROM AUTHOR]

ABSTRACT A novel ultrawideband (UWB) bandpass filter (BPF) with a quad band-notched function is investigated using a modified H-shaped resonator. The proposed H-shaped resonator, which exhibits quadruple resonance characteristics, is realized without any change in its overall size by modifying the simplified composite right/left-handed resonator exhibiting dual resonance characteristics. The proposed resonator is integrated into a conventional UWB BPF. The notching frequencies are located at 2.41, 3.42, 5.3, and 5.9 GHz, and the attenuations at the center frequency of the four notched bands are at least 13 dB. The proposed UWB BPF has the advantages of compact size, low insertion loss, good selectivity, and flat delays. © 2014 Wiley Periodicals, Inc. Microwave Opt Technol Lett 56:2286-2289, 2014 [ABSTRACT FROM AUTHOR]

A wideband fractal slot antenna is proposed, designed, and fabricated in this communication. The broadband characteristic is achieved by introducing a Sierpinski fractal into a square wide slot without increasing the overall antenna size. A simple microstrip line is used to excite the Sierpinski-based slot. As the iteration order of the Sierpinski square radiator increases, the number of resonance increases, and the bandwidth of the slot antenna is enhanced. From the measured results, the 10 dB reflection coefficient bandwidth of the 2nd iteration Sierpinski slot antenna is 63.4%. [ABSTRACT FROM AUTHOR]

This letter proposes a novel microstrip resonator that can perform filtering and radiating functions simultaneously.The proposed structure consists of outer ring, inner ring, circular patch, and three ports. The operating frequencies ( f and f) for a filter and an antenna are different. At the lower band, in which the center frequency is f, the proposed structure represents the characteristics of a wideband bandpass filter that has three transmission poles in a passband. Also, the proposed structure is operated as a radiating element at f. The measured isolation between the filter and the antenna is less than −25 dB over the entire impedance bandwidth for the filter and the antenna. © 2011 Wiley Periodicals, Inc. Microwave Opt Technol Lett 53:940-943, 2011; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.25884 [ABSTRACT FROM AUTHOR]

Microstrip antennas inherently have a high input impedance at resonant frequency. This may not be convenient for some applications. For active integrated antennas, moreover, the radiated power of microstrip antennas needs to be very low at harmonic frequencies. The main goals of this study are impedance matching and harmonic suppression of microstrip antennas. In order to meet these requirements, two one-dimensional (1-D) photonic bandgap (PBG) structures, namely, the defected ground structure (DGS) and the compact microstrip resonant cell (CMRC), are applied to the feed line of microstrip antennas. The characteristic impedance of the microstrip line is controlled by the additional effective inductance of the PBG structure. Without any matching circuits, microstrip antennas can be easily fed by a simple 50Ω microstrip line with a PBG structure at the operating frequency. Additionally, the second harmonic of the proposed antennas is properly suppressed compared to a conventional antenna. Measured results Indicate that the two PBG structures are quite effective for harmonic suppression. Therefore, the proposed antennas are suitable for active integrated antennas. [ABSTRACT FROM AUTHOR]

Differential display was used to identify synapse-enriched mRNAs. Of 15 mRNAs initially identified, all were found in multiple synaptoneurosome preparations; 58% were subsequently shown to be enriched in all the preparations by Northern blotting and semiquantitative RT-PCR. RNAs involved in signal transduction, vesicle trafficking, lipid modification and cell shape and remodeling were among these messages. Tip60a mRNA, recently found to associate with the fragile X mental retardation protein, was also identified. These data demonstrate the diversity of the local message pool at synapses. [Copyright &y& Elsevier]

A tunable triangular microstrip patch antenna is proposed for multiband applications in this letter. The proposed antenna consists of varactor diodes and F-shaped slits. As the input impedance of the antenna can be varied by changing the bias voltage of the varactor diode on the F-shaped slits, the resonant frequency may be changed. The designed antenna has return losses better than 20 dB within 1.95–2.16 GHz. The peak gains of the antenna present 2.87 and 3.1 dBi at the both ends of the above frequency range. Details of the antenna design are described. Its performances are also presented. © 2009 Wiley Periodicals, Inc. Microwave Opt Technol Lett 51: 1788–1790, 2009; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.24428 [ABSTRACT FROM AUTHOR]

In this letter, the miniaturized bandstop filter with lumped capacitor element is presented. The resonator is based on a stopband characteristic of U-shaped defected ground structure (DGS) section. Lumped capacitor element is embedded into DGS section without altering the geometry. The resonant frequency of DGS section is significantly lowered in accordance with increase of capacitor value. The DGS section with different capacitance values is designed and fabricated. From the measured results, size reduction over 60% is achieved by this method. © 2009 Wiley Periodicals, Inc. Microwave Opt Technol Lett 51: 802–804, 2009; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.24152 [ABSTRACT FROM AUTHOR]

The article focuses on circular polarised (CP) microstrip patch antennas for broadband and dual-band operation. Microstrip patch antennas have attracted much attention due to their low profile, light weight and easy fabrication. They are usually designed for singlemode operation that radiates mainly linear polarisation. In some applications such as satellite communication systems, however, CP system is more suitable because of its insensitivity to transmitter and receiver orientations. For a CP radiator, a patch resonator must support orthogonal fields of equal amplitude, but in-phase quadrature.

A novel single-feed structure for circularly polarised square patch antennas is proposed and theoretically studied. The proposed antenna has a simple structure, consisting of a square radiating patch and an asymmetrical Y-shaped microstrip feed line. The two orthogonal modes with equal amplitude and ±90° out of phase are simultaneously excited by the suggested feed structure with two different branch lengths. It is shown that the proposed antenna has good circular polarisation characteristic. [ABSTRACT FROM AUTHOR]

A novel technique for designing a tunable dual-band microstrip patch antenna is proposed. Dual-band operation is easily achieved by loading a microstrip patch antenna with one varactor diode placed on a small gap between a square patch and a parasitic strip. It is observed from the measured result that the proposed antenna shows a wide tuning range at the two resonant frequencies. [ABSTRACT FROM AUTHOR]

Abstract-A novel design of patch antennas with polarization diversity is proposed and experimentally studied in this letter. A pair of L-type slits is embedded into the edge of square patch and the shape of the slit is changed according to ON- or OFF- state of PIN diode. Therefore, the proposed patch antenna has different polarizations. The novel structure we describe here enables the optimization of the input match for both polarizations. From the measured result, low cross-polarization levels in the linear state and good axial ratios in the circular state are observed. [ABSTRACT FROM AUTHOR]

In this article, an inverted planar monopole antenna with two shorting plates is proposed. This inverted planar monopole antenna provides a 3.55:1 impedance bandwidth (for VSWR < 2). Owing to its compact size and wide impedance bandwidth, this antenna is suitable for CDMA, GSM, DCS, PCS, and wireless LAN (IEEE 802.11b) applications. © 2007 Wiley Periodicals, Inc. Microwave Opt Technol Lett 49: 2913–2914, 2007; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.22900 [ABSTRACT FROM AUTHOR]

Brucellosis is one of the most common systemic zoonotic diseases transmitted by consumption of unpasteurized dairy products or by occupational contact with infected animals. Brucellosis is rare in renal transplant recipients. Only 3 cases have been reported in the literature. We report a case of brucellosis with hematologic and hepatobiliary complications in a patient 3 years after renal transplantation. The mean time from transplantation to the diagnosis of brucellosis in these 4 reported patients was 5.1 years (range 17 months to 13 years). All patients had fever and constitutional symptoms, and all attained clinical cure after combination antibiotic therapy. Given the small number of patients, further study is needed to identify the characteristics of brucellosis in renal transplant recipients. Drug interactions and acute renal failure developed in our patient during antibiotic treatment. Therefore, we should monitor the levels of immunosuppressive agents frequently. Several studies have shown in vitro susceptibilities of Brucella melitensis to tigecycline. In our patient, fever finally subsided after tigecycline administration. The minimum inhibitory concentration of tigecycline using Etest was 0.094 μg/mL. Tigecycline may be a potential option for treatment of brucellosis in the setting of transplantation. [ABSTRACT FROM AUTHOR]

We performed a genome-wide linkage scan using highly polymorphic microsatellite markers. To minimize genetic heterogeneity, we focused on sibpairs meeting the strict diagnosis of autism. In our primary analyses, we observed a strong linkage signal (P=0.0006, 133.16 cM) on chromosome 7q at a location coincident with other linkage studies. When a more relaxed diagnostic criteria was used, linkage evidence at this location was weaker (P=0.01). The sample was stratified into families with only male affected subjects (MO) and families with at least one female affected subject (FC). The strongest signal unique to the MO group was on chromosome 11 (P=0.0009, 83.82 cM), and for the FC group on chromosome 4 (P=0.002, 111.41 cM). We also divided the sample into regression positive and regression negative families. The regression-positive group showed modest linkage signals on chromosomes 10 (P=0.003, 0 cM) and 14 (P=0.005, 104.2 cM). More significant peaks were seen in the regression negative group on chromosomes 3 (P=0.0002, 140.06 cM) and 4 (P=0.0005, 111.41 cM). Finally, we used language acquisition data as a quantitative trait in our linkage analysis and observed a chromosome 9 signal (149.01 cM) of P=0.00006 and an empirical P-value of 0.0008 at the same location. Our work provides strong conformation for an autism locus on 7q and suggestive evidence for several other chromosomal locations. Diagnostic specificity and detailed analysis of the autism phenotype is critical for identifying autism loci.Molecular Psychiatry (2006) 11, 1049–1060. doi:10.1038/sj.mp.4001874; published online 1 August 2006 [ABSTRACT FROM AUTHOR]

The output power of InGaN multiple-quantum-well laser diodes (LDs) emitting at 405 nm wavelength is compared for several Al composition in the AlGaN n-cladding layer. The Al composition has been varied from 2% to 6% to study the effect of n-cladding refractive index on threshold current and slope efficiency of the LDs. As the Al composition in the AlGaN n-cladding layer increases, both threshold current and slope efficiency decrease. This behavior can be explained by the change in optical field distribution with refractive index of the AlGaN n-cladding layer. It is found that the Al composition of ¿4% would be advantageous for achieving more than 100 mW output power and high level of catastrophic optical damage. [ABSTRACT FROM AUTHOR]

In this study, transparent indium tin oxide (ITO) deposited by sputtering was applied to laser lift-off (LLO) GaN-based vertical light-emitting diodes (VLEDs) and the electrical and optical properties of ITO films were measured as a function of annealing conditions. The measured minimum resistivity of ITO film was about 3.78×10-4 Ω cm and the measured optical transmittance at 460 nm was 96.8% after the annealing process. In this condition, about 1×10-5 Ω cm2 of ITO contact resistance to LLO n-GaN could be obtained. By applying the transparent ITO layer to the LLO GaN-based VLEDs, a significant decrease of the forward operating voltage from 3.3 to 3.8 V at 20 mA could be obtained. [ABSTRACT FROM AUTHOR]

In this study, 6H-SiC wafers were etched using a magnetically enhanced inductively coupled SF6 abased plasmas (ME1CP) and their etch characteristics were investigated. The etch characteristics of SIC and the etch selectivities over metal thin films such as Cu and Ni were investigated as a function of inductive power, operating pressure, additive gas percentage, etc To understand the etch mechanism, the etched SIC and Cu surfaces were examined by X-ray photoelectron spectroscopy (XI'S) and the radical and ion densities in the plasmas were measured by optical emission spectroscopy (OES) and a Langmuir probe, respectively. The obtained highest etch rate was about 1.9 μm/mm with 90%SF 6/10%O2. By XPS analysis, it could be confirmed that the addition of small oxygen percentage assisted in forming volatile SiFx by the reaction with carbon on the SIC surface. In our experimental conditions, the increase of thickness by the formation of a reaction product instead of etching was observed on the Cu mask layer, therefore, the calculated selectivity of SiC to Cu was infinite. Using the Cu mask, 80-100 μm thick SiC substrates could be fully etched with vertical etch profiles and smooth etch side walls. [ABSTRACT FROM AUTHOR]

The article presents a table showing evidence for genetic linkage of autism to chromosomes 7 and 4.

InGaN optical confinement layers (OCLs) were introduced into blue-violet AlInGaN-based laser diodes (LDs), resulting in the drastic improvements of lasing performance. Comparing with conventional LD structure, the lowest threshold current density of 2.3 kA/cm2 has been achieved by adding 100-nm-thick InGaN OCLs which represented maximum optical confinement factor. Additionally, we observed the high quantum efficiency and the uniform emission intensity distribution of InGaN quantum wells grown on lower InGaN OCL than on typical GaN layer. Upper InGaN OCL can reduce Mg diffusion from p-type layers to InGaN active region by separating the distance between InGaN quantum wells and p-type layers. [ABSTRACT FROM AUTHOR]

We demonstrated the long wavelength (485 nm) lasing of InGaN laser diodes under continuous wave condition at room temperature over 10 mW. Two InGaN laser structures were adapted with different indium composition for InGaN optical confinement layers (OCLs) below quantum wells. The blue shift of electroluminescence (EL) was reduced in InGaN laser diodes grown on 3% In concentration in InGaN OCL compared with 1.5% In concentration in InGaN OCL. The EL peak for laser diode with 3% In concentration in InGaN OCL occurs at longer wavelength for all current levels compared to the laser with 1.5% In concentration in InGaN OCL. In addition, the laterally nonuniform InGaN wells grown on 1.5% In concentration in InGaN OCL was verified by the cross-sectional view of InGaN active layer using high-resolution transmission electron microscopy. [ABSTRACT FROM AUTHOR]

We report stable temperature characteristics of threshold current and output power in InGaN blue laser diodes emitting around 450 nm. The threshold current is changed by <3 mA in operation temperature range from 20 to 80 °C, and even negative characteristic temperature is observed in a certain temperature range. This peculiar temperature characteristic is attributed to originate from unique carrier transport properties of InGaN quantum wells with high In composition, which is deduced from the simulation of carrier density and optical gain. In addition, slope efficiency is also maintained well and wall plug efficiency is even improved as temperature increases. [ABSTRACT FROM AUTHOR]