bluuebunny/crossref_metadata_2025 huggingface dataset:
Patients are Not Cars and Staff are Not Robots: Impact of Differences between Manufacturing and Clinical Operations on Process Improvement
Authors: Guo Lin , Hariharan Selena
Published: April 2012

Long recognized by industry as a key component for advancement of business, process improvement is only now being incorporated into healthcare systems. Unfortunately, despite proven success in manufacturing, these same methods are often met with resistance when proposed to the healthcare sector, largely because leaders in the healthcare industry have always considered patient care more an art than a science. This attitude and the attendant value of autonomy are especially prevalent among physicians and nurses who provide direct clinical care to patients. Using specific examples, this paper outlines some of the key differences between manufacturing and healthcare operations, underscores the unique milieu of the healthcare industry, and proposes some solutions to successfully initiate process improvement for clinical operations without compromising individualized care for each patient. Copyright © 2012 John Wiley & Sons, Ltd.
Early regeneration of the remnant liver volume after right hepatectomy for living donation: A multiple regression analysis
Authors: Gruttadauria Salvatore , Parikh Vishal , Pagano Duilio , Tuzzolino Fabio , Cintorino Davide , Miraglia Roberto , Spada Marco , Vizzini Giovanbattista , Luca Angelo , Gridelli Bruno
Published: April 2012

Early liver regeneration was studied in a series of 70 patients who underwent right hepatectomy for living donation between November 2004 and January 2010. Liver regeneration was evaluated with multidetector computed tomography (MDCT) at a mean of 61.07 days after surgery. Presurgical variables [eg, age, weight, height, body mass index (BMI), liver function tests, creatinine levels, platelet counts, international normalized ratio, and glucose levels] and variables detected with preoperative MDCT imaging [eg, main portal vein diameter, steatosis, original liver volume, and spleen volume (SV)] were investigated as potential predictors of liver regeneration. The future remnant liver volume (FRLV) was preoperatively calculated with a virtual surgical cut. Liver function tests and creatinine levels were recorded on the 30th postoperative day. In addition, the onset of postoperative complications occurring within 90 days of surgery was analyzed, and the complications were codified according to the 5 tiers of the Clavien-Dindo classification. In 26 of the 70 patients (37.14%), 100% or greater hepatic regeneration had occurred at 2 months. There was no association between the clinical outcome and the liver regeneration rate. A stepwise multiple regression analysis showed that a higher BMI (coefficient = 0.035, P < 0.0001) and preoperative parameters such as a smaller FRLV (coefficient = −0.002, P < 0.0001) and a greater SV/FRLV ratio (coefficient = 1.196, P < 0.0001) were predictors of greater liver regeneration. Liver Transpl, 2012. © 2012 AASLD.
Design of circular monopole antenna with symmetrically folded stub for WLAN operation
Authors: Seo Yongseok , Jung Jinwoo , Lee Hyeonjin , Lim Yeongseog
Published: April 2012

A novel and simple design of a coplanar waveguide‐fed dual‐wide band antenna formed by a circular monopole antenna with symmetrically folded stub is investigated for wireless local area network (WLAN) applications.The impedance bandwidths achieved reach about 1.27 GHz (1.92–3.19 GHz) 58.8% at the center frequency of 2.16 and 0.76 GHz (5.01–5.74 GHz) 13.3% at the center frequency of 5.47 GHz. These characteristics meet the required bandwidth specifications of IEEE 802.11a/b/g. The peak antenna gains for the operating frequencies across dual WLAN bands are measured to be 6.30 and 5.16 dBi, respectively. © 2012 Wiley Periodicals, Inc. Microwave Opt Technol Lett 54:1549–1552, 2012; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.26845
Compact planar ultrawideband wide‐slot antenna with an assembled band‐notched structure
Authors: Zeng Wenbo , Zhao Jia , Wu Qiqi
Published: April 2012

A simple and compact wide‐slot antenna and its extended band‐notched design are presented.The proposed antenna is etched on a piece of FR4 printed circuit board with an overall size of 30 × 28 × 0.8 mm3. It consists of a polygonal wide slot, a coplanar waveguide feeding line, and a circular metal ring. The antenna prototype achieves good impedance matching, a constant gain, and stable radiation patterns over an operating bandwidth of 3.1–10.6 GHz. Furthermore, after the addition of an assembled band‐notch structure, which is formed by a pair of inverted L‐shaped slits embedded in the ground plane and a T‐shaped stub inside the metal ring, the proposed antenna exhibits band‐notched characteristics and achieves a much sharper notch band at 5–6 GHz. © 2012 Wiley Periodicals, Inc. Microwave Opt Technol Lett 54:1654–1659, 2012; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.26864
A low phase noise oscillator using a new high‐q resonator with μ‐near zero metamaterial
Authors: Yoon Ki‐Cheol , Lee Hyunwook , Lee Dong‐Ki , Kim Ki‐Byoung , Lee Jong‐Chul
Published: April 2012

This article proposed a new high‐QLresonator with a combination of a double spiral resonator and single split ring resonator with μ‐ near zero metamaterial.It is applied to the design of an X‐band oscillator. A very low phase noise for the oscillator can be obtained due to its sharp band‐ rejection characteristic of the new resonator. The oscillator is designed to operate at 9.2 GHz using the new resonator. Experimental results show the output power is 14.13 dBm, the second harmonic suppression is −46.33 dBc, and the phase noise is −104.54 dBc/Hz at 100‐kHz offset. © 2012 Wiley Periodicals, Inc. Microwave Opt Technol Lett 54:1577–1582, 2012; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.26867
Integration of monopole slot and monopole strip for internal WWAN handset antenna
Authors: Wong Kin‐Lu , Lin Po‐Wei
Published: April 2012

A novel internal handset antenna formed by a monopole slot and a monopole strip for the wireless wide area network (WWAN) operation in the 824–960 and 1710–2170 MHz bands is presented. The monopole strip is disposed in the monopole slot, and both are embedded in the system ground plane of the handset with a small board space of 9 × 40 mm2 at about the bottom edge of the circuit board. The monopole strip serves as a feed for the monopole slot and also functions as an efficient radiator. In the proposed design, the monopole slot generates a quarter‐wavelength slot mode in the antenna's lower band, while the monopole strip contributes its quarter‐wavelength mode in the antenna's upper band. By including a vertical strip that can be enclosed inside the handset casing or be a part of the bezel surrounding, the periphery of the handset casing and connected to the bottom edge of the system ground plane, the impedance matching of the excited slot mode can be greatly improved. In this case, the proposed antenna can provide two wide operating bands with good impedance matching to cover the pentaband WWAN operation. Detailed operating principle of the integrated monopole slot and monopole strip for the internal WWAN handset antenna is described. The proposed antenna is also fabricated and obtained results are presented and discussed. © 2012 Wiley Periodicals, Inc. Microwave Opt Technol Lett 54:1718–1723, 2012; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.26870
High gain Fermi antenna array for radar‐aided radiotherapy system
Authors: Salmani Zeeshan , Gu Changzhan , Li Changzhi , Zhang Hualiang
Published: April 2012

This article presents the design of Fermi antenna array with improved gain for radar respiration measurement. A six‐element Fermi antenna array working at 5.8 GHz is optimally designed and integrated with the respiration radar system. Specifically, to easily feed the antenna array as well as reduce the total size of the array system, a feeding network based on 0‐degree phase shifters is used along with suitable impedance transformers. The whole system is proposed to function as a radar sensor for respiration rate measurement, which is known as a promising noncontact and noninvasive approach for lung cancer radiotherapy. The measurement results verify the improved performance of the proposed system for radar respiration measurement in motion‐adaptive lung cancer radiotherapy. © 2012 Wiley Periodicals, Inc. Microwave Opt Technol Lett 54:1649–1654, 2012; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.26871
Dual‐grid multiresolution technique for electrically large BoR‐FDTD simulation
Authors: Dahlan Samsul , Rolland Anthony , Sauleau Ronan
Published: April 2012

The dual‐grid (DG) technique is implemented in the body‐of‐revolution FDTD algorithm (BoR‐FDTD) for the fast analysis of large rotationally symmetric antennas.The proposed technique combines two BoR‐FDTD simulations performed successively with fine and coarse mesh schemes, respectively. First, all excitation sources are analyzed locally with a fine mesh resolution and the near‐field distributions are saved. Second, the whole problem (feeds and scatterers) is modeled using a coarser mesh where the computational domain is excited by the equivalent sources stored at the first stage. The continuity between these two simulations is guarantied by means of linear field interpolation or sampling (in space and time) and total/scattered field formulation. The relevance of the proposed technique is demonstrated through the analysis of a 60 × λ0 parabolic antenna system illuminated by an electromagnetic band gap feed. The DG technique is found to be accurate and faster than the classical BoR‐FDTD approach. Our results also show that significant savings are obtained in terms of computation time and memory. The DG‐BoR‐FDTD strategy is considered as a powerful and flexible approach to analyze the influence of the surrounding environments without having to repeat the expensive part of the simulation. © 2012 Wiley Periodicals, Inc. Microwave Opt Technol Lett 54:1714–1718, 2012; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.26873
A novel compact dual‐frequency monopole antenna for quad‐band mobile terminal application
Authors: Kang Gaojian , Du Zhengwei
Published: April 2012

A novel compact dual‐frequency monopole antenna with a parasitic radiating strip is presented. The antenna with a height of only 6.5 mm, printed on the upper board and side board, is vertically placed at the upper‐left corner of the main board to reduce the occupied area of the main board. A parasitic strip with meandered structure is added into the antenna, and hence, the dual‐frequency characteristic is achieved to broaden the bandwidth. The measured −10 dB impedance bandwidth is 960 MHz (1920–2880 MHz), covering the UMTS (1920–2170 MHz), WiBro (2300–2400 MHz), WLAN (2400–2483 MHz), and WiMAX (2500–2690 MHz) bands. Thus, the proposed antenna is suitable for multisystem mobile terminal applications. © 2012 Wiley Periodicals, Inc. Microwave Opt Technol Lett 54:1743–1746, 2012; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.26876
Four‐tap microwave photonic filter with tunable center frequency and reconfigurable transfer function
Authors: Wang Yi , Jin Xiaofeng , Xu Kai , Ou Jianhai , Chi Hao , Zhang Xianmin , Zheng Shilie
Published: April 2012

A four‐tap microwave photonic filter with tunable center frequency and reconfigurable transfer function is proposed.It is based on two Mach‐Zehnder interferometers (MZIs) cascaded with a variable optical coupler (OC) in between. By simultaneously adjusting the variable optical delay line incorporated in each MZI, center frequency of the filter can be tuned continuously. Reconfiguration of the filter is achieved by changing the coupling ratio of the variable OC. Experimental result demonstrates a tunable four‐tap filter with sidelobe suppression in excess of 25 dB. © 2012 Wiley Periodicals, Inc. Microwave Opt Technol Lett 54:1740–1743, 2012; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.26877
Fiber‐optic in‐line michelson temperature sensor
Authors: Park Jaehee , Shin Jong Duk
Published: April 2012

This article presents a fiber‐optic in‐line Michelson temperature sensor with the high sensitivity.The in‐line Michelson interferometer used as a fiber‐optic temperature sensor is composed of a hollow optical fiber spliced to a single‐mode standard optical fiber at one end and cleaved at the other end. As the fabrication procedure involving fusion splicing and cleaving, the fiber‐optic in‐line Michelson temperature sensor is much easier and cheaper to make. The relation between the phase shift and temperature is approximately linear and the sensor sensitivity is about 3.1 radian/°C. © 2012 Wiley Periodicals, Inc. Microwave Opt Technol Lett 54:1699–1701, 2012; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.26879
Wide upper‐stopband microstrip bandpass filter with dual‐mode open loop stepped‐impedance resonator and source‐load coupling structure
Authors: Deng Hong‐Wei , Zhao Yong‐Jiu , Chen Wen , Liu Bing , Liu Yan‐Yun
Published: April 2012

In this article, a dual‐mode microstrip bandpass filter (BPF) with compact size, sharp skirt, and wide upper‐stopband performance is proposed using the short‐stub‐loaded open loop stepped‐impedance resonator and source‐load coupling structure. The advantageous features of the resonator are that the even‐mode resonant frequencies can be controlled exclusively by the short stub, and two transmission zeros are created near the passband by the short stub and the folded arms. Meanwhile, two transmission zeros generated by the source‐load coupling structure can be applied to suppress the first and second spurious harmonics. Finally, a microstrip BPF located at 2.4 GHz with a fractional bandwidth 4% is designed, fabricated, and measured. The upper stopband in experiment is extended up to 20 GHz with an insertion loss lower than −21.2 dB. © 2012 Wiley Periodicals, Inc. Microwave Opt Technol Lett 54:1618–1621, 2012; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.26881
Bandwidth enhancement of a printed dipole antenna for wideband applications
Authors: Fan S. T. , Yin Y.Z. , Hu W. , Li B. , Yang J. H.
Published: April 2012

The design of a novel printed dipole antenna with bandwidth enhancement is proposed for wideband applications. The antenna consists of an integrated balun, two rectangular radiating arms and a modified inductive coplanar stripline (CPS) impedance tuner. By adjusting the parameters of the CPS‐tuner and the balun properly, a good performance of bandwidth enhancement is achieved. The measured results indicate that the impedance bandwidth of the proposed antenna, defined by 10‐dB return loss, is about 73.9% from 2.54 to 5.52GHz. In addition, good omnidirectional radiation characteristics are also obtained over the whole operating band. © 2012 Wiley Periodicals, Inc. Microwave Opt Technol Lett 54:1585–1590, 2012; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.26883
Single‐layer circular polarizer using metamaterial and its application in antenna
Authors: Ma Xiaoliang , Huang Cheng , Pu Mingbo , Hu Chenggang , Feng Qin , Luo Xiangang
Published: April 2012

In this letter, we report a new type of circular polarizer using a single‐layer metamaterial. The unit cell is composed of a metallic annular‐ring and an embedded strip. Numerical and experimental results show that the linearly polarized plane wave can be converted to circularly polarized wave with a 3‐dB axial ratio bandwidth of about 17%, which is from 13.25 to 15.7 GHz. The polarizer can also keep good circular polarization with incident off‐normal angle in the range of ±30°. Subsequently, this polarizer is applied in the linearly polarized microstrip patch antenna as superstrate, making this antenna composite radiate circularly polarized wave. In addition, the antenna gain is enhanced by about 3 dB in comparison with conventional patch antenna without polarizer. © 2012 Wiley Periodicals, Inc. Microwave Opt Technol Lett 54:1770–1774, 2012; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.26884
Microstrip lowpass filter based on split ring and complementary split ring resonators
Authors: Yang Yang , Zhu Xi , Karmakar Nemai C.
Published: April 2012

A novel split ring and complementary split ring resonator is proposed in this letter.The proposed resonator can generate two notches without increasing the physical size. A microstrip lowpass filter (LPF) is designed based on the proposed resonator. The cutoff frequency of the designed LPF is 3.7 GHz and the stopband with an attenuation level lower than −20 dB is obtained from 3.9 to 7.5 GHz. The selectivity is calculated to be 85 dB/GHz. The physical size of the LPF with transmission lines is 29 × 6 mm2. A good agreement between simulated and measured results is achieved. © 2012 Wiley Periodicals, Inc. Microwave Opt Technol Lett 54:1723–1726, 2012; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.26887
H‐shaped SIR bandpass filter with dual and tri‐band
Authors: Xiao Jian‐Kang , Zhu Wen‐Jun
Published: April 2012

Compact dual‐band bandpass filter which meets IEEE 802.11 application requirements by using new H‐shaped tri‐section stepped‐impedance resonator is proposed, and a tri‐band bandpass filter which achieves insertion loss of 0.41, 0.66, and 1.65 dB at 2.5, 3.49, and 5.6 GHz, respectively, is also designed with two‐path coupling. The new designs are demonstrated by experiment. The new filters have advantages of compact structures, low passband insertion losses, good frequency selectivity, and miniature circuit sizes. All these have prospect to be applied in future wireless communication systems. © 2012 Wiley Periodicals, Inc. Microwave Opt Technol Lett 54:1686–1688, 2012; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.26888
Two‐poles compact microstrip bandpass filter with sharp transition bands using high permittivity substrate
Authors: Yang Wen‐Ruei , Huang Cheng‐Liang
Published: April 2012

This article describes the two‐pole microstrip band‐pass filters using miniaturized center‐stubbed open stubs and tapped‐line input/output ports. The two‐poles bandpass filters by using FR4 and high‐permittivity ceramic substrates (with respective dielectric constants of 4.5 and 31.55) are investigated. Microwave dielectric ceramics with high permittivity are commonly applied in several microwave communication components. The advantage of using high permittivity ceramic substrates is to reduce the sizes and increase the performance of microstrip bandpass filters. The responses of the filters using FR4 (εr = 4.5, tan δ = 0.015) and Nd(Zn1/2Ti1/2)O3 (εr = 31.55, tan δ= 0.00005) ceramic substrates are designed at a center frequency of 2 GHz. The compact size, low‐loss, sharp response, and performance of the filter are presented in this article. © 2012 Wiley Periodicals, Inc. Microwave Opt Technol Lett 54:1683–1686, 2012; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.26889
Sensing of hydrostatic pressure using FBG sensor for liquid level measurement
Authors: Sengupta D. , Sai Shankar M. , Saidi Reddy P. , Sai Prasad R.L. N. , Srimannarayana K.
Published: April 2012

Pressure and temperature are two important parameters in hydrostatic pressure based liquid level sensing. In this study, we propose a liquid level sensor based on hydrostatic pressure variation sensed by fiber Bragg grating (FBG1) attached to a bourdon tube. The water column pressure sensitivity coefficient of FBG1 is 0.072 nm/m. One more FBG2 is incorporated to avoid cross sensitivity of temperature. The temperature sensitivity coefficient of the FBG1 and FBG2 are 10.5 pm/°C and 10.2 pm/°C. The packaged sensor head can be placed inside a chamber and also easily mountable external to the tank for the measurement of liquid level. © 2012 Wiley Periodicals, Inc. Microwave Opt Technol Lett 54:1679–1683, 2012; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.26890
Large anisotropic inhomogeneous higher order hierarchical generalized hexahedral finite elements for 3‐D electromagnetic modeling of scattering and waveguide structures
Authors: Manić Ana B. , Manić Sanja B. , Ilić Milan M. , Notaroš Branislav M.
Published: April 2012

A higher order large‐domain finite element technique for three‐dimensional modeling of electromagnetic structures involving general anisotropic inhomogeneous materials is presented.The examples demonstrate efficient and accurate simulations of scattering and waveguide structures using large (a couple of wavelengths across) anisotropic continuously inhomogeneous curved finite elements with p‐refined (high‐order) field distributions. © 2012 Wiley Periodicals, Inc. Microwave Opt Technol Lett 54:1644–1649, 2012; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.26892
Full colorless gigabit wavelength‐division multiplexed‐passive optical network supporting simultaneous two different data transmission
Authors: Won Yong‐Yuk , Kim Hyun‐Seung , Son Yong‐Hwan , Han Sang‐Kook
Published: April 2012

A novel wavelength‐division multiplexed‐passive optical network scheme supporting the transmission of heterogeneous data and broadcast signal is proposed in this article. Both optical carrier suppression and multiplexing of arrayed waveguide grating with 50‐GHz channel spacing are used to generate each optical carrier for the transmission of these data. A reflective semiconductor optical amplifier is also used, so that this architecture operates irrespective of wavelength. In case of downlink transmission, error‐free transmissions (bit error rate of 10−11) of 1.25‐ and 2.5‐Gb/s baseband data are achieved at the same time. Also, 64‐quadrature amplitude modulation signal of 60 Mb/s is transmitted showing the error vector magnitude of 4.7% in the presence of the transmission of 2.5‐Gb/s baseband data. © 2012 Wiley Periodicals, Inc. Microwave Opt Technol Lett 54:1757–1761, 2012; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.26893
A 2.6–3.4 GHz low‐voltage LC‐VCO with a boosted transconductance
Authors: Lee Hui Dong , Jung Jae Ho
Published: April 2012

A 2.6–3.4 GHz low‐voltage voltage‐controlled oscillator (VCO) with a boosted transconductance is presented. The proposed VCO operates with less current dissipation for oscillation start‐up, being enabled to supply voltage reduction. The phase noise of the proposed VCO is improved by not entering in deep triode region of MOSFETs. Implemented in a 65‐nm CMOS, the measurements results show 800 MHz of tuning range, consuming 1.56 mW at 0.6 V supply. The measured phase noise is −116 dBc/Hz at 1 MHz offset from a 3.3‐GHz carrier. © 2012 Wiley Periodicals, Inc. Microwave Opt Technol Lett 54:1671–1674, 2012; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.26898
High‐capacity radio frequency identification‐based radio over fiber system
Authors: Udomariyasap P. , Noppanakeepong S. , Mitatha S. , Yupapin P.P.
Published: April 2012

We present the use of a serial ring resonator system for multichannel radio frequency generation that can be used to form the radio frequency identification (RFID) application. A system consists of a serial nonlinear microring resonator system for generating pulse and selecting signals that can be filtered by using the add/drop filter. The input pulse is a Gaussian pulse with center wavelength at 1,500 nm. By using suitable simulation microring parameters, the generation of signal with the center wavelength or frequency at 2.15 nm or 285 GHz is achieved, where the high frequency RFID with 91 channels is generated and noted. The use of THz frequency enhancement and RFID‐based wireless communication is discussed. © 2012 Wiley Periodicals, Inc. Microwave Opt Technol Lett 54:1637–1642, 2012; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.26899
Q‐factor improvement of integrated inductors using high aspect ratio ferromagnetic nanowires
Authors: Hamoir Gael , Piraux Luc , Huynen Isabelle
Published: April 2012

We fabricated a planar inductor onto a substrate made of high aspect ratio ferromagnetic nickel nanowires in a self‐supported alumina nanoporous membrane. We observe a simultaneous increase of the inductance value and the quality factor up to 7 GHz, thanks to the large amount of ferromagnetic material and the nanoscale of the wires limiting conducting losses. Our device shows the largest increase reported in the literature for such ferromagnetic inductors: +30% for the inductance value and +23% for the quality factor. Even more, this technology offers great advantages as an easy integration in miniaturized topologies and its tunability to a magnetic field to broaden the desired frequency range. Our analytical model predicts that the increase of quality factor can be maximized up to 35% by an optimization of the pores filling. © 2012 Wiley Periodicals, Inc. Microwave Opt Technol Lett 54:1633–1637, 2012; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.26900
Active integrated meshed patch antennas for small satellites
Authors: Genc Alper , Turpin Timothy , Yasin Tursunjan , Baktur Reyhan
Published: April 2012

Meshed microstrip antennas are optically see‐through when printed on transparent substrates and can potentially be directly integrated on solar cells to save surface real estate of small satellites.Integrating active components such as amplifiers with see‐through antennas further extends multifunctionality of solar panels. Two active integrated meshed patch antennas were studied at 2.48 GHz. The antennas serve as loads for class‐B power amplifiers and as radiators. As a reference, the first design was a regular meshed antenna integrated with an amplifier. In the second design, the antenna was modified to suppress its second harmonics to improve the power added efficiency (PAE) of the integrated amplifier. It was shown that the PAE of the second design is increased by the harmonics suppression. The maximum PAE was measured to be 47.2% for the harmonics suppressing meshed antenna, and the output power is 15.8 dBm at the peak PAE. © 2012 Wiley Periodicals, Inc. Microwave Opt Technol Lett 54:1593–1595, 2012; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.26906
Analytical design of novel dual‐band cross‐coupled substrate integrated waveguide filter
Authors: Chen J. , Chen J.‐Z. , Fu S. , Liang C.‐H.
Published: April 2012

A dual‐band substrate integrated waveguide (SIW) filter is presented in this article. The dual‐band cross‐coupled design procedure is based on the frequency transformation from the normalized frequency domain to the actual frequency domain, which can calculate the coupling coefficients and the external quality factors analytically. The cross‐coupled SIW filter has the flexibility to achieve different kinds of filtering characteristics with the same coupling structure. To validate the method, a practical SIW dual‐band filter operating at 5.85–5.95 GHz and 6.05–6.15 GHz is designed and fabricated. © 2012 Wiley Periodicals, Inc. Microwave Opt Technol Lett 54:1609–1612, 2012; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.26908
Compact CPW‐fed monopole antenna and miniaturized ACS‐fed half monopole antenna for UWB applications
Authors: Fei Peng , Jiao Yong‐Chang , Zhu Yang , Zhang Fu‐Shun
Published: April 2012

A novel coplanar waveguide‐fed monopole ultra wideband (UWB) antenna and its miniaturized version of an asymmetric coplanar strip‐fed half monopole antenna are proposed.Both of the antennas are compact in size and simple in configuration. Numerical and experimental results indicate that the antennas are capable of working in the desired UWB band. © 2012 Wiley Periodicals, Inc. Microwave Opt Technol Lett 54:1605–1609, 2012; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.26909
An active nonreciprocal phase shifter topology
Authors: Ciccognani Walter , Limiti Ernesto , Palomba Mirko , Scucchia Lucio
Published: April 2012

A novel hybrid active nonreciprocal phase shifter (NRPS) topology is proposed in this contribution. A test vehicle of the topology, realized in hybrid form to operate in L‐band with a 90° differential phase shift has been realized and tested. The resulting system exhibits a 28% bandwidth centered at 1.4 GHz. © 2012 Wiley Periodicals, Inc. Microwave Opt Technol Lett 54:1659–1661, 2012; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.26913
Modeling and practical demonstration of multiple optical fiber ring resonators in the microwave domain
Authors: Merrer P. H. , Llopis O. , Nicole P. , Constant S.
Published: April 2012

The modeling and practical demonstration of optical fiber ring resonators for microwave bandpass filters in the X‐band are proposed. Experimental investigations on the microwave behavior of the device have been performed. A third‐order optical filter at 8.8 GHz with 180 MHz bandwidth and 3 dB insertion loss is shown. © 2012 Wiley Periodicals, Inc. Microwave Opt Technol Lett 54:1552–1556, 2012; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.26915
Alternative AEFIE‐EFIE method for broadband CEM simulations
Authors: Liu Jia , Jiang Lijun
Published: April 2012

It is well known that electric field integral equation (EFIE) has the low frequency breakdown problem due to the decoupling of electric and magnetic field. Augmented electric field integral equation (AEFIE) method overcomes the low frequency breakdown. However, its performance degrades with the increasing frequency. To obtain a unified method that works for both low and high frequencies, a novel method using the EFIE complement process inside AEFIE is proposed. Numerical results demonstrated that this alternative AEFIE‐EFIE method is able to extend integral equations to wide band applications. © 2012 Wiley Periodicals, Inc. Microwave Opt Technol Lett 54:1737–1740, 2012; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.26919
Solid‐state 11B and 13C NMR, IR, and X‐ray crystallographic characterization of selected arylboronic acids and their catechol cyclic esters
Authors: Oh Se‐Woung , Weiss Joseph W. E. , Kerneghan Phillip A. , Korobkov Ilia , Maly Kenneth E. , Bryce David L.
Published: April 2012

Nine arylboronic acids, seven arylboronic catechol cyclic esters, and two trimeric arylboronic anhydrides (boroxines) are investigated using 11B solid‐state NMR spectroscopy at three different magnetic field strengths (9.4, 11.7, and 21.1 T). Through the analysis of spectra of static and magic‐angle spinning samples, the 11B electric field gradient and chemical shift tensors are determined. The effects of relaxation anisotropy and nutation field strength on the 11B NMR line shapes are investigated. Infrared spectroscopy was also used to help identify peaks in the NMR spectra as being due to the anhydride form in some of the arylboronic acid samples. Seven new X‐ray crystallographic structures are reported. Calculations of the 11B NMR parameters are performed using cluster model and periodic gauge‐including projector‐augmented wave (GIPAW) density functional theory (DFT) approaches, and the results are compared with the experimental values. Carbon‐13 solid‐state NMR experiments and spectral simulations are applied to determine the chemical shifts of the ipso carbons of the samples. One bond indirect 13C‐11B spin‐spin (J) coupling constants are also measured experimentally and compared with calculated values. The 11B/10B isotope effect on the 13C chemical shift of the ipso carbons of arylboronic acids and their catechol esters, as well as residual dipolar coupling, is discussed. Overall, this combined X‐ray, NMR, IR, and computational study provides valuable new insights into the relationship between NMR parameters and the structure of boronic acids and esters. Copyright © 2012 John Wiley & Sons, Ltd.
Transperineal prostate MR elastography: Initial in vivo results
Authors: Sahebjavaher Ramin S. , Baghani Ali , Honarvar Mohammad , Sinkus Ralph , Salcudean Septimiu E.
Published: April 2012

This article presents a new approach to magnetic resonance elastography of the prostate using transperineal mechanical excitation. This approach is validated using a prostate elasticity phantom and in vivo studies of healthy volunteers. It is demonstrated that the transperineal approach can generate shear wave amplitudes on the order of 6–30 μm in the mid‐gland region. The driver was implemented using an electromagnetic actuator with a hydraulic transmission system. The magnetic resonance elastography acquisition time has been reduced significantly by using a “second harmonic” approach. Displacement fields are processed using the established three‐dimensional local frequency estimation algorithm. The three‐dimensional curl‐based direct inversion was used to calculate the local wavelength. The traveling wave expansion algorithm was used to reconstruct the wave damping image for one case. Using the proposed method, it was possible to resolve lesions of 0.5 cc in the phantom study. Repeatability experiments were performed and analyzed. The results from this study indicate that transperineal magnetic resonance elastography—without an endorectal coil—is a suitable candidate for a patient study involving multiparametric magnetic resonance imaging of prostate cancer, where magnetic resonance elastography may provide additional information for improved diagnosis and image‐based surveillance. Magn Reson Med, 2013. © 2012 Wiley Periodicals, Inc.
Elimination of dysphagia using ultrasound guidance for botulinum toxin injections in cervical dystonia
Authors: Hong Justin S. , Sathe Geeta G. , Niyonkuru Christian , Munin Michael C.
Published: April 2012

Introduction: Dysphagia is a common side effect after botulinum toxin injections for cervical dystonia, with an incidence of 10–40%, depending upon the study and dose used. Methods: Our study consisted of 5 preselected women who met criteria for cervical dystonia and subsequent dysphagia after electromyography (EMG)‐guided injections. Injections were performed with ultrasound (US) imaging, and the effects on swallowing were examined. Separately, sternocleidomastoid (SCM) thickness in healthy controls and treated patients was measured. Results: There were 34 episodes of dysphagia over 98 injection sessions using EMG guidance for a cumulative rate of 34.7%. Using US plus EMG guidance, there was 0% dysphagia across 27 injection sessions. SCM thickness was <1.1 cm. Conclusion: US combined with EMG guidance eliminated recurrent dysphagia after botulinum toxin treatment, possibly by keeping the injectate within the SCM. Muscle Nerve 46: 535–539, 2012
Manual needle placement: Accuracy of botulinum toxin a injections
Authors: Schnitzler Alexis , Roche Nicholas , Denormandie Philippe , Lautridou Christine , Parratte Bernard , Genet François
Published: April 2012

Introduction: Electrophysiological or ultrasound guidance can facilitate botulinum toxin A (BoNt‐A) injection accuracy, but clinical landmarks and palpation are often used for superficial muscles. We evaluated the accuracy of manual needle placement in the gastrocnemius muscles (GC) guided only by anatomical landmarks and palpation. Methods: Bilateral limbs from 30 cadavers were used to evaluate ink injection into the GC. One anatomist and one orthopedic surgeon verified the accuracy of manual needle placement postinjection by calf muscle dissection. Injection was considered a failure if the ink was not located in the head of the target GC. Results: One hundred twenty‐one practitioners were evaluated. Fifty‐two injections were successful (43%), and 69 failed (57%). This result was unrelated to injector experience (P = 0.097). Conclusions: Our findings show a poor success rate, regardless of injector experience. Therefore, muscle palpation and anatomical landmarks are insufficient to ensure the accuracy of BoNt‐A injections, even for large, superficial muscles. Muscle Nerve 46: 531–534, 2012
Alterations of signaling pathways in muscle tissues of patients with amyotrophic lateral sclerosis
Authors: Yin Fei , Ye Fei , Tan Limei , Liu Katherine , Xuan Zhaopeng , Zhang Jinnan , Wang Wenhu , Zhang Yanli , Jiang Xinmei , Zhang David Y.
Published: April 2012

Introduction: Amyotrophic lateral sclerosis (ALS), a degenerative disorder of the central nervous system, manifests as progressive weakening of muscles. The diagnosis and prognosis of ALS are often unclear, so useful biomarkers are needed. Methods: Total proteins were extracted from muscle samples from 36 ALS, 17 spinal muscular atrophy (SMA), and 36 normal individuals. The expression levels of 134 proteins and phosphoproteins were assessed using protein pathway array analysis. Results: Seventeen proteins were differentially expressed between ALS and normal muscle, and 9 proteins were differentially expressed between ALS and SMA muscle. The low‐level expression of Akt and Factor XIIIB correlates with unfavorable survival, and the risk score calculated based on these proteins predicts the survival of each individual patient. Conclusions: Some proteins could be selected as clinically useful biomarkers. Specifically, Akt and Factor XIIIB were found to be promising biomarkers for estimating prognosis in ALS. Muscle Nerve, 2012
Reliability of side‐to‐side ultrasound cross‐sectional area measurements of lower extremity nerves in healthy subjects
Authors: Tagliafico Alberto , Cadoni Angela , Fisci Erica , Bignotti Bianca , Padua Luca , Martinoli Carlo
Published: April 2012

Introduction: In peripheral nerve ultrasound, the healthy contralateral side may be used as internal control. Therefore, inherent side‐to‐side differences must be minimal. The goal of this study was to assess intrastudy, intraobserver, and interobserver reproducibility of ultrasound in comparative side‐to‐side evaluation of lower limb nerves. Methods: Lower limb nerves of 60 normal subjects were evaluated by 3 radiologists. Bilateral sciatic, tibial, common fibular, sural, lateral femoral cutaneous, femoral, obturator, and saphenous nerves were evaluated. Results: Overall, side‐to‐side differences were not statistically significant at any level. In the lower limb nerves, in a between‐limb comparison, the minimum detectable difference of cross‐sectional area ranged from 16.4 mm2 (sciatic nerve at the level of piriformis muscle) to 0.4 mm2 (saphenous nerve). Conclusion: In general, the healthy contralateral side can be used as an internal control. Muscle Nerve 46: 717–722, 2012
Diaphragm pacing in amyotrophic lateral sclerosis: A literature review
Authors: Scherer Katalin , Bedlack Richard S.
Published: April 2012

Amyotrophic lateral sclerosis (ALS) remains a rapidly progressive fatal degenerative disease of motor neurons for which there are few interventions to slow disease progression or improve quality of life. A diaphragm pacing system was approved by the U.S. Food and Drug Administration in September 2011 for ALS under a Humanitarian Device Exemption. News of this approval has been met with a combination of excitement and uncertainty by members of the ALS community. We review the currently available data on the diaphragm pacing system and its use in ALS. Diaphragm pacing appears to be reasonably safe in carefully selected patients, but flaws in the reporting on it thus far preclude conclusions regarding efficacy. Further study is needed. Muscle Nerve 46: 1–8, 2012
Structural analysis of a 3‐deoxy‐D‐arabino‐heptulosonate 7‐phosphate synthase with an N‐terminal chorismate mutase‐like regulatory domain
Authors: Light Samuel H. , Halavaty Andrei S. , Minasov George , Shuvalova Ludmilla , Anderson Wayne F.
Published: April 2012

3‐Deoxy‐D‐arabino‐heptulosonate 7‐phosphate synthase (DAHPS) catalyzes the first step in the biosynthesis of a number of aromatic metabolites. Likely because this reaction is situated at a pivotal biosynthetic gateway, several DAHPS classes distinguished by distinct mechanisms of allosteric regulation have independently evolved. One class of DAHPSs contains a regulatory domain with sequence homology to chorismate mutase—an enzyme further downstream of DAHPS that catalyzes the first committed step in tyrosine/phenylalanine biosynthesis—and is inhibited by chorismate mutase substrate (chorismate) and product (prephenate). Described in this work, structures of the Listeria monocytogenes chorismate/prephenate regulated DAHPS in complex with Mn2+ and Mn2+ + phosphoenolpyruvate reveal an unusual quaternary architecture: DAHPS domains assemble as a tetramer, from either side of which chorismate mutase‐like (CML) regulatory domains asymmetrically emerge to form a pair of dimers. This domain organization suggests that chorismate/prephenate binding promotes a stable interaction between the discrete regulatory and catalytic domains and supports a mechanism of allosteric inhibition similar to tyrosine/phenylalanine control of a related DAHPS class. We argue that the structural similarity of chorismate mutase enzyme and CML regulatory domain provides a unique opportunity for the design of a multitarget antibacterial.
Full geometry optimizations of the mixed‐valence CaMn4O4X(H2O)4 (X=OH or O) cluster in OEC of PS II: Degree of symmetry breaking of the labile Mn‐X‐Mn bond revealed by several hybrid DFT calculations
Authors: Yamaguchi K. , Isobe H. , Yamanaka S. , Saito T. , Kanda K. , Shoji M. , Umena Y. , Kawakami K. , Shen J.‐R. , Kamiya N. , Okumura M.
Published: April 2012

Several hybrid DFT methods were applied to full geometry optimizations of the CaMn4O4X(H2O)4 (XOH1− (1) or O2− (2)) cluster in the oxygen evolving complex (OEC) of photosystem II (PSII) to elucidate Mn‐Mn, Mn‐Ca, and Mn‐O distances on a theoretical ground. The computed Mn‐Mn distances were compared with previous (London and Berlin) X‐ray diffraction (XRD), and Berkeley and Berlin EXAFS results, together with the recent high‐resolution XRD structure by Umena and coworkers. Present computational results by the hybrid DFT methods have elucidated several differences among these accumulated results. These DFT results led us to reassign the Mn‐Mn and Mn‐Ca distances by the EXAFS experiments, which became consistent with the results obtained by the high‐resolution XRD structure. A characteristic feature revealed via the optimized Mn‐O distances was that the degree of symmetry breaking of the Mn1‐O(57)‐Mn4 bond is not so remarkable under the UBHandHLYP approximation but it can be large by other hybrid DFT methods. The computational results for 2 indicated reduction of the Mn3‐Mn4 distance with the deprotonation of the bridging oxo group. The hybrid DFT results for 1 are not inconsistent with an experimental proposal based on the new XRD structure, namely a protonated μ3‐oxygen at the internal O(57) site of the cluster in the S1 state. On the other hand, the reduction of Mn ions (not degradation of whole cluster structure) by the X‐ray irradiation still remains an important issue for refinements of the XRD structure. The computational results are discussed in relation to those of the electron spin echo envelope modulation (ESEEM) and possible pathways for water splitting reaction. Implications of the present DFT structures are discussed in relation to the previous DFT and related computational results, together with recent XRD results for cubane‐like model clusters for OEC of PSII. © 2012 Wiley Periodicals, Inc.
A comprehensive analysis of hydrogen bond interactions based on local vibrational modes
Authors: Freindorf Marek , Kraka Elfi , Cremer Dieter
Published: April 2012

Local stretching modes for 69 different DH single bonds and 58 H···A H‐bonds are calculated at the ωB97X‐D/aug‐cc‐pVTZ level of theory to describe the changes in donor D and acceptor A upon forming the hydrogen‐bonded complex. The intrinsic strength of the DH and AH interactions is determined utilizing the properties of a well‐defined set of local, uncoupled vibrational modes. The local mode stretching force constantka(HA) provides a unique measure of bond strength for both covalently and electrostatically bonded complexes. Generally applicable bond orders are derived, which can be related to the binding energies of the hydrogen bonded complexes. Although the red shifts in the DH stretching frequencies can be used to detect hydrogen bonding, they are not sufficient to assess the strength of hydrogen bonding. It is demonstrated that the calculated BSSE‐corrected binding energies of hydrogen bonded complexes are related to the sum of bond order changes caused by hydrogen bonding. The covalent character of charge assisted hydrogen bonds is explained. Because local mode frequencies can also be derived from experimental normal mode frequencies, a new dimension in the study of hydrogen bonding is gained. © 2012 Wiley Periodicals, Inc.
Measurement of the 17O‐excess (Δ17O) of tropospheric ozone using a nitrite‐coated filter
Authors: Vicars William C. , Bhattacharya S. K. , Erbland Joseph , Savarino Joël
Published: April 2012

RATIONALE

The 17O‐excess (Δ17O) of tropospheric ozone (O3) serves as a useful marker in studies of atmospheric oxidation pathways; however, due to the complexity and expense of currently available analytical techniques, no systematic sampling campaign has yet been undertaken and natural variations in Δ17O(O3) are therefore not well constrained.

METHODS

The nitrite‐coated filter method is a new technique for O3 isotope analysis that employs the aqueous phase NO2– + O3 → NO3– + O2 reaction to obtain quantitative information on O3 via the oxygen atom transfer to nitrate (NO3–). The triple‐oxygen isotope analysis of the NO3– produced during this reaction, achieved in this study using the bacterial denitrifier method followed by isotope‐ratio mass spectrometry (IRMS), directly yields the Δ17O value transferred from O3. This isotope transfer process was investigated in a series of vacuum‐line experiments, which were conducted by exposing coated filters to O3 of various known Δ17O values and then determining the isotopic composition of the NO3– produced on the filter.

RESULTS

The isotope transfer experiments revealed a strong linear correlation between the Δ17O of the O3 produced and that of the oxygen atom transferred to NO3–, with a slope of 1.55 for samples with bulk Δ17O(O3) values in the atmospheric range (20–40‰). This finding is in agreement with theoretical postulates that place the 17O‐excess on only the terminal oxygen atoms of ozone. Ambient measurements yield average Δ17O(O3)bulk values in agreement with previous studies (22.9 ± 1.9‰).

CONCLUSIONS

The nitrite‐coated filter technique is a sufficiently robust, field‐deployable method for the determination of the triple‐oxygen isotopic composition of tropospheric O3. Further ambient measurements will undoubtedly lead to an improved quantitative view of natural Δ17O(O3) variation and transfer in the atmosphere. Copyright © 2012 John Wiley & Sons, Ltd.