bluuebunny/crossref_metadata_2025 huggingface dataset:
Effects of tensile strain and fluid flow on osteoarthritic human chondrocyte metabolism in vitro
Authors: Mawatari Taro , Lindsey Derek P. , Harris Alex H.S. , Goodman Stuart B. , Maloney William J. , Smith Robert L.
Published: January 2010

This study examined the hypothesis that tensile strain and fluid flow differentially influence osteoarthritic human chondrocyte metabolism. Primary high‐density monolayer chondrocytes cultures were exposed to varying magnitudes of tensile strain and fluid‐flow using a four‐point bending system. Metabolic changes were quantified by real‐time PCR measurement of aggrecan, IL‐6, SOX‐9, and type II collagen gene expression, and by determination of nitric oxide levels in the culture medium. A linear regression model was used to investigate the roles of strain, fluid flow, and their interaction on metabolic activity. Aggrecan, type II collagen, and SOX9 mRNA expression were negatively correlated to increases in applied strain and fluid flow. An effect of the strain on the induction of nitric oxide release and IL‐6 gene expression varied by level of fluid flow (and visa versa). This interaction between strain and fluid flow was negative for nitric oxide and positive for IL‐6. These results confirm that articular chondrocyte metabolism is responsive to tensile strain and fluid flow under in vitro loading conditions. Although the articular chondrocytes reacted to the mechanically applied stress, it was notable that there was a differential effect of tensile strain and fluid flow on anabolic and catabolic markers. © 2010 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 28:907–913, 2010
Activation of signal transducer and activator of transcription 3 (Stat3) pathway in osteosarcoma cells and overexpression of phosphorylated‐Stat3 correlates with poor prognosis
Authors: Ryu Keinosuke , Choy Edwin , Yang Cao , Susa Michiro , Hornicek Francis J. , Mankin Henry , Duan Zhenfeng
Published: January 2010

Stat3 expression in cancer may have important prognostic and therapeutic value, but there has been no reports correlating Stat3 expression with prognosis in patients with osteosarcoma. The goal of this study is to correlate patient prognosis with the expression of Stat3 in osteosarcoma tissue and determine the effectiveness of blocking this pathway in osteosarcoma cell lines by Stat3 inhibitor, CDDO‐Me. We examine the expression levels of Stat3 and pStat3 in osteosarcoma cell lines and primary tissues by Western blot analysis. We also evaluate the levels of pStat3 expression in osteosarcoma tissue microarray (TMA) by immunohistochemistry. We use clinical data to determine the impact of levels of Stat3 expression on patient prognosis. Finally, we evaluated the effect of CDDO‐Me on the inhibition of activated Stat3 pathway in osteosarcoma cell lines using MTT assay and Western blot analysis. Stat3 is observed to be activated in osteosarcoma tissues as well as in cultured cell lines. Overexpression of pStat3 is associated with poor prognosis. CDDO‐Me inhibits the growth of osteosarcoma cell lines and induces apoptosis as well. Our results suggest that Stat3 may be a prognostic indicator and potential therapeutic target for osteosarcoma. Blocking the pathway of Stat3 may lead to develop new therapeutic strategies against osteosarcoma. © 2010 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 28:971–978, 2010
Gastrointestinal stromal tumors: Current management
Authors: Pisters Peter W.T. , Patel Shreyaskumar R.
Published: January 2010

Herein, we review the current management of localized and advanced gastrointestinal stromal tumors (GISTs). Although surgery remains the standard of care for patients with localized GIST, adjuvant imatinib can delay recurrence in some of these patients. In patients with advanced or metastatic disease, the standard of care is imatinib and surgery of residual masses is an option. Preoperative imatinib is an emerging treatment option for patients who require cytoreductive therapy. Sunitinib is a standard second‐line therapy. J. Surg. Oncol. 2010;102:530–538. © 2010 Wiley‐Liss, Inc.
Chemical‐kinetic modeling of ignition delay: Considerations in interpreting shock tube data
Authors: Chaos Marcos , Dryer Frederick L.
Published: January 2010

High‐pressure shock tube ignition delays have been and continue to be one of the key sources of data that are important to characterizing the combustion properties of real fuels. At pressures and temperatures of importance to practical applications, concerns have recently been raised as to the large differences observed between experimental data and chemical‐kinetic predictions using the common assumption that the shock tube behaves as a constant volume (V) system with constant internal energy (U). Here, a concise review is presented of phenomena that can considerably affect shock tube data at the extended test times (several milliseconds or longer) needed for the measurement of fuel/air ignition at practical conditions (i.e., high pressures and relatively low temperatures). These effects include fluid dynamic nonidealities as well as deflagrative processes typical of mild ignition events. Proposed modeling approaches that attempt to take into account these effects, by employing isentropic assumptions and pressure‐ and temperature‐varying systems, are evaluated and shown to significantly improve modeling results. Finally, it is argued that at the conditions of interest ignition delay data do not represent pure chemical‐kinetic observations but are affected by phenomena that are in some measure facility specific. This hampers direct cross comparison of the experimental ignition data collected in different venues. In such cases, pressure/temperature histories should be provided in order to properly interpret shock tube ignition data. © 2010 Wiley Periodicals, Inc. Int J Chem Kinet 42: 143–150, 2010
Determination of the rate coefficients of the SO2 + O + M → SO3 + M reaction
Authors: Hwang S. M. , Cooke J. A. , De Witt K. J. , Rabinowitz M. J.
Published: January 2010

Rate coefficients of the title reaction R31 (SO2 + O + M → SO3 + M) and R56 (SO2 + HO2→ SO3 + OH), important in the conversion of S(IV) to S(VI), were obtained at T = 970–1150 K and ρave = 16.2 μmol cm−3 behind reflected shock waves by a perturbation method. Shock‐heated H2/O2/Ar mixtures were perturbed by adding small amounts of SO2 (1%, 2%, and 3%) and the OH temporal profiles were then measured using laser absorption spectroscopy. Reaction rate coefficients were elucidated by matching the characteristic reaction times acquired from the individual experimental absorption profiles via simultaneous optimization of k31 and k56 values in the reaction modeling (for satisfactory matches to the observed characteristic times, it was necessary to take into account R56). In the experimental conditions of this study, R31 is in the low‐pressure limit. The rate coefficient expressions fitted using the combined data of this study and the previous experimental results are k31,0/[Ar] = 2.9 × 1035 T−6.0 exp(−4780 K/T) + 6.1 × 1024 T−3.0 exp(−1980 K/T) cm6 mol−2 s−1 at T = 300–2500 K; k56 = 1.36 × 1011 exp(−3420 K/T) cm3 mol−1 s−1 at T = 970–1150 K. Computer simulations of typical aircraft engine environments, using the reaction mechanism with the above k31,0 and k56 expressions, gave the maximum S(IV) to S(VI) conversion yield of ca. 3.5% and 2.5% for the constant density and constant pressure flow condition, respectively. Moreover, maximum conversions occur at rather higher temperatures (∼1200 K) than that where the maximum k31,0 value is located (∼800 K). This is because the conversion yield is dependent upon not only the k31,0 and k56 values (production flux) but also the availability of H, O, and HO2 in the system (consumption flux). © 2010 Wiley Periodicals, Inc.*

This article is a U.S. Government work and, as such, is in the public domain of the United States of America.

Int J Chem Kinet 42: 168–180, 2010
The treatment of psychogenic movement disorders with suggestion is ethically justified
Authors: Shamy Michel C. F.
Published: January 2010

Recent developments in our understanding of psychogenic movement disorders have not yet led to advances in treatment. A potentially beneficial treatment strategy is suggestion, the voluntary use by the physicians of techniques that introduce into the patient's mind a belief that he or she will be healed. Principalism, the dominant school of contemporary medical ethics, holds that the use of suggestion is not ethically justifiable because it undermines patient autonomy and degrades the doctor–patient relationship. However, evidence from a variety of sources (neuroimaging, anecdote, expert opinion, randomized controlled trials, and meta‐analysis) supports the efficacy of suggestion as a treatment for psychogenic movement disorders. When issues of choice, consent, deceit, disclosure, and decision‐making are analyzed from the perspective of an ethics of care, we see that suggestion may enhance patient autonomy and does not violate the trust between doctors and their patients. I conclude that suggestion is therefore an ethically justifiable treatment for patients with psychogenic movement disorders. © 2009 Movement Disorder Society
Parkinsonism in patients with a history of amphetamine exposure
Authors: Christine Chadwick W. , Garwood Elisabeth R. , Schrock Lauren E. , Austin Daniel E. , McCulloch Charles E.
Published: January 2010

We recently found a higher rate of prolonged amphetamine exposure in patients diagnosed with Parkinson's disease (PD) than in spouse/caregiver controls. Since distinguishing features have been described in some patients with parkinsonism due to environment exposures (e.g., manganese), we sought to compare the clinical features of patients with PD with prolonged amphetamine exposure with unexposed patients with PD. Prolonged exposure was defined as a minimum of twice a week for ≥3 months, or weekly use ≥1 year. We reviewed the clinical records of patients with PD who had participated in a telephone survey of drug and environmental exposures and compared the clinical features of patients with a history of prolonged amphetamine exposure to patients who had no such exposure. Records were available for 16 of 17 (94%) patients with prior amphetamine exposure and 127 of 137 (92%) of those unexposed. Age at diagnosis was younger in the amphetamine‐exposed group (49.8 ± 8.2 years vs. 53.1 ± 7.4 years; P < 0.05), but other features, including presenting symptoms, initial and later treatments, development of motor fluctuations, and MRI findings were similar between these groups. Because we did not detect clinical features that differentiate parkinsonism in patients with prolonged amphetamine exposure, research to determine whether amphetamine exposure is a risk factor for parkinsonism will require detailed histories of medication and recreational drug use. © 2009 Movement Disorder Society
Trihexyphenidyl for acute life‐threatening episodes due to a dystonic movement disorder in Rett syndrome
Authors: Gika Artemis D. , Hughes Elaine , Goyal Sushma , Sparkes Matthew , Lin Jean‐Pierre
Published: January 2010

In Rett syndrome (RS), acute life‐threatening episodes (ALTEs) are usually attributed to epilepsy or autonomic dysfunction but they can represent a movement disorder (MD). We describe three girls with RS who experienced ALTEs from an early age. These were long considered epileptic until video‐EEG in Patients 1 and 3 revealed their non‐epileptic nature. A primary dystonic mechanism was suspected and Patients 1 and 2 were treated with Trihexyphenidyl with significantly reduced frequency of the ALTEs. Patient 3 died before Trihexyphenidyl was tried. Trihexyphenidyl in RS patients with similar presentations can modify the dystonia and prevent ALTEs. © 2009 Movement Disorder Society
Millimeter‐wave CMOS power amplifier based on tapered device sizing for high efficiency using standard digital CMOS
Authors: Lee Jong‐Wook , Lee Seong‐Gwon
Published: January 2010

A high‐efficiency Q‐band CMOS power amplifier was fabricated using a 0.13 μm standard CMOS process with six layers of copper metallization.To achieve high efficiency, a tapered device sizing technique was employed with a common‐source transistor rather than a cascode configuration. Using tapered device sizing, DC power consumption was reduced by using small size transistors in the driver stage while maintaining the overall amplifier gain and output power. Therefore, a good figure of merit including high efficiency was obtained. The amplifier achieved a 15.2 dB small‐signal gain, 7.5 dBm output power, and 9.2% power‐added‐efficiency at 36.5 GHz in a compact chip area of 0.3 mm2. © 2010 Wiley Periodicals, Inc. Microwave Opt Technol Lett 52: 514–518, 2010; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.24958
Compact quintplexer module with passive triplexer for US‐CDMA handset applications
Authors: Cheon Seong J. , Park Jae Y.
Published: January 2010

In this article, compact quintplexer modules with a passive triplexer circuit were newly designed, implemented, compared for US‐CDMA handset applications.The proposed passive triplexer circuit was comprised of a single diplexer, parallel resonant circuit, bandpass filter for GPS, and its impedance matching circuit. Although the number of passive components to comprise the proposed triplexer and its size were dramatically reduced, its performance characteristics were much better than the previously reported modules. Moreover, for realization of compact quintplexer module with small size and volume, FBAR filter bare chips and system in package technology were utilized instead of an US‐PCS packaged duplexer. Its excellent performances were good enough to directly apply for currently used handsets. Simulated and measured performance characteristics of fabricated triplexer and quintplexer module were well agreed. The fabricated quintplexer module had a 7.0 × 5.0 × 1.4 mm3 volume. © 2010 Wiley Periodicals, Inc. Microwave Opt Technol Lett 52: 540–543, 2010; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.24959
A novel tunable dual‐band low noise amplifier for 868/915 MHz and 2.4 GHz Zigbee application by CMOS technology
Authors: Xuan Kai , Fung Tsang Kim , Ching Lee Wah
Published: January 2010

A dual‐band (868/915 MHz and 2.4 GHz) low noise amplifier for Zigbee applications is designed using 0.35‐μm CMOS technology.At 868/915 MHz and 2.4 GHz, the gains achieved are both 16 dB and the resulting noise figures are about 2.5 dB and 2.7 dB, respectively. The input and the output reflections are below −10 dB in both bands. The amplifier works at 2.5 V supply voltage with 12 mA current dissipation. © 2010 Wiley Periodicals, Inc. Microwave Opt Technol Lett 52: 507–510, 2010; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.24964
Excellent sensitivity 64.8‐GHz CMOS injection‐locked frequency divider with 10.2‐GHz locking range
Authors: Chen Chang‐Zhi , Chen Tsung‐Yen , Lin Yo‐Sheng , Huang Guo‐Wei
Published: January 2010

A low‐power and wide‐locking‐range 64.8‐GHz injection‐locked frequency‐divider (ILFD) using standard 0.13 μm CMOS technology is reported. To enhance the locking range, a shunt inductor was introduced in the source node of the cross‐coupled transistor pair to maximize the equivalent load impedance of the tail transistor, i.e., to maximize the internal power, over the frequency band of interest. In addition, the inductors and capacitors of the LC‐tank were implemented by low‐Q micro‐stripline inductors and high‐Q varactors, respectively, to further improve the locking range of the ILFD. The result shows that a wide locking‐range of 10.2 GHz (from 54.6 GHz to 64.8 GHz (17%)), covering the 57–64‐GHz ultra‐wideband (UWB) set aside by FCC of USA, was achieved. The ILFD can be operated at an input power of −60 dBm. To the authors' knowledge, this is the best input sensitivity ever reported for a 60‐GHz‐band CMOS divider. The power consumption of the ILFD was only 3.39 mW from a 1 V power supply. The chip area was only 0.9 × 0.73 mm2 excluding the test pads. © 2010 Wiley Periodicals, Inc. Microwave Opt Technol Lett 52: 518–523, 2010; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.24970
Wideband cross‐coupled filter using defected stepped impedance resonator
Authors: Wu Bian , Lai Xin , Su Tao , Liang Chang‐Hong
Published: January 2010

A novel wideband cross‐coupled band‐pass filter based on defected stepped impedance resonator (DSIR) is presented in this article. Although the DSIR has opposite impedance characteristic and field distribution to the microstrip SIR, its resonant property is similar to the latter. The internal coupling coefficients of DSIRs are found to be large enough for the wideband filter design. A four‐pole, cross‐coupled band‐pass filter with f0 = 1.6 GHz and FBW = 12% is designed and fabricated using the folded DSIR. Experimental result has good agreement with the simulation. © 2010 Wiley Periodicals, Inc. Microwave Opt Technol Lett 52: 558–561, 2010; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.24972
A compact ultra‐wide stopband, low insertion loss, and sharp cutoff low‐pass filter
Authors: Fu Shu‐Hong , Tong Chuang‐Ming , Li Xi‐Min , Shen Kai
Published: January 2010

A novel compact microstrip low‐pass filter (LPF) with ultra‐wide stopband, low insertion loss, and sharp cutoff is introduced in this letter. The LPF is composed of a stepped‐impedance hairpin resonator, a square split‐ring resonator, defected ground structure (DGS), and a pair of coupled DGSs with compensated microstrip lines. Measured results show that the 10‐dB stopband is up to 19.62 GHz, passband loss is below 0.5 dB, and the selectivity of the filter is more than 180 dB/GHz, but its occupied area is only 20 × 35 mm2. It can be widely used for higher harmonics suppression for wideband microwave applications. © 2010 Wiley Periodicals, Inc. Microwave Opt Technol Lett 52: 568–570, 2010; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.24976
Compact high performance dielectric disk antenna for WiMAX application
Authors: Ivanchenko Igor V. , Khruslov Maksym M. , Popenko Nina A.
Published: January 2010

The simulation and measurement results relative to the radiation characteristics of dielectric disk antennas with the axial‐symmetric excitation are presented. The compact dielectric disk antenna with the −10 dB impedance bandwidth of Δf = 4.1 GHz and mono‐beam radiation pattern is manufactured and tested. The excitation more than one resonances and formation of the multi‐beam radiation pattern for antenna with substrate radius rs > 45 mm is explained by the appearance of standing waves along the substrate radius. The choice of relation between the dielectric disk radius and substrate height allows for designing a set of antennas operating from f = 5–21.77 GHz. At that the bandwidth and gain of antennas are changed within the limits 1.6 < Δf < 2.7 GHz and 4 < G < 6 dBi, respectively. © 2010 Wiley Periodicals, Inc. Microwave Opt Technol Lett 52: 580–584, 2010; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.24980
Loss characteristics of coplanar waveguide transmission lines fabricated with copper nanoparticles
Authors: Lee Hee‐Jo , Seo Shanghoon , Yun Kwansoo , Joung Jae Woo , Yook Jong‐Gwan
Published: January 2010

This article investigates the high frequency characteristics of coplanar waveguide (CPW) lines fabricated with inkjet‐printing technology on BT substrates. The optimal metallic thickness of a printed CPW line is approximately estimated to be 3 μm. When printed lines with higher electrical conductivity are realized through additional surface preparation steps, the findings of this study suggest that the RF performance level of these printed lines will be comparable to that of the copper clad laminate lines in the microwave frequency region. Finally, aspects of such improvements as well as applications of these types of printed lines are discussed. © 2010 Wiley Periodicals, Inc. Microwave Opt Technol Lett 52: 780–782, 2010; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.24987
A novel hybrid planar SIW magic tee and monopulse antenna
Authors: Liu Minggang , Feng Zhenghe
Published: January 2010

In this article, a novel planar substrate integrated waveguide (SIW) magic Tee is proposed, and the magic Tee is implemented in a monopulse antenna design. Although the E arm is lain down, the magic Tee is of good performance. The magic Tee is used in a monopulse SIW slot array, and the beam pattern is measured. © 2010 Wiley Periodicals, Inc. Microwave Opt Technol Lett 52: 686–689, 2010; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.24990
Discrete diffraction in two‐dimensional transmission line metamaterials
Authors: Bhat Harish S. , Osting Braxton
Published: January 2010

We describe the efficient and accurate numerical solution of propagation problems in composite and dual‐composite right/left‐handed metamaterials using a discrete diffraction formula based on lattice Green's functions. For both metamaterials and for physically realizable parameters, we find that the observed diffraction patterns depend strongly on the temporal input frequency. © 2010 Wiley Periodicals, Inc. Microwave Opt Technol Lett 52: 721–725, 2010; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.24991
Design and evaluation of a −117 dBc/Hz phase noise voltage‐controlled oscillator using on‐chip CPW resonator for 5 GHz‐band WLAN
Authors: Pokharel Ramesh K. , Kanaya Haruichi , Yoshida Keiji
Published: January 2010

A 5 GHz‐band voltage‐controlled oscillator employing on‐chip coplanar‐waveguide resonator instead of inductor–capacitor–resonator is proposed, designed, and fabricated in 0.18 μm CMOS technology.The advantages of the proposed VCO are the wider frequency‐tuning range; smaller chip area and phase noise is to be −117 dBc/Hz (@1 MHz offset frequency), which is comparable to that of a conventional LC–VCO. © 2010 American Association of Anatomists Microwave Opt Technol Lett 52: 763–766, 2010; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.24993
Switching‐capacitor current‐reused VCO with symmetrical differential outputs
Authors: Wang Ruey‐Lue , Lin Min‐Chuan , Tzeng Yu‐Jo , Yang Cheng‐Fu , Lin Yi‐Shu
Published: January 2010

In this article, we present two switching‐capacitor current‐reused voltage‐controlled oscillators with two sub‐bands or four sub‐bands. The degeneration source resistors are used to improve magnitude symmetry of output signals. Tuning frequency range is from 2.16 to 2.74GHz. The phase noise is better than −104 dBc/Hz at 100 kHz frequency offset. © 2010 Wiley Periodicals, Inc. Microwave Opt Technol Lett 52: 600–604, 2010; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.24994
Scaleable comprehensive low‐noise PHEMT model that predicts IP3 and noise
Authors: Wei Ce‐Jun , Zhu Yu , Klimashov Oleksiy , Li Binhui , Cebi Haki , Zhang Cindy , Tkachenko Yevgeniy , Bartle Dylan
Published: January 2010

Correlation of IP3 in a phemt with the third derivative of Ids wrt Vgs, or Gm3 is addressed.A nonlinear large‐signal Phemt model was developed based on the fitting RF Gm characteristics as well as IV/CV. Systematic extraction approach is described. In extraction, RF Gm fitting minimizes the errors between modelled and measured Gm3. Scale‐ability in terms of DC, S‐parameters, and IP3 is demonstrated. For large‐size devices, other factors, such as RF‐Gds characteristics, are also important. Modelling of accurate noise response is realized with linear lookup table data based noise model and nonlinear voltage/current sampler. The over‐all model includes also physics‐based dynamic thermal effect and scaleable measurement‐based noise model that makes it the most comprehensive and most practical in industry. © 2010 Wiley Periodicals, Inc. Microwave Opt Technol Lett 52: 604–611, 2010; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.24995
A novel dual‐band balun using branch‐lines with open stubs
Authors: Yoon Yang Seung , Sik Cho Choon , Lee Jae W. , Kim Jaeheung
Published: January 2010

This letter presents a novel dual‐band balun using the branch‐line configuration. We establish design equations for dual‐band balun based on the even‐odd mode method. The proposed circuit operates at 2.45 GHz and 5.25 GHz. The single‐ended power is divided differentially at the balanced ports. The insertion losses (S21 and S31) show around −2.7 dB to −4.3 dB at the two different frequencies. The phase difference between the balanced ports shows maximum 3° deviation from 180°. © 2010 Wiley Periodicals, Inc. Microwave Opt Technol Lett 52: 642–644, 2010; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.24996
Reconfigurable defected ground structure cell using PIN diodes on Coplanar Waveguide technology
Authors: El‐Shaarawy Heba B. , Coccetti Fabio , Plana Robert , El‐Said Mostafa , Hashish Essam A.
Published: January 2010

This article addresses a novel reconfigurable defected ground structure resonator fabricated on Coplanar Waveguide (CPW) technology. The resonator is endowed with an original design that enables the generation of multiple transmission zeros at arbitrary frequencies. The chosen design is indeed based on a slot defect created on the lateral ground planes of the CPW with the double advantage to allow a simple reconfiguration, by means of surface mounted (or fabricated) components, and a compact solution, by exploiting the transversal dimension of the CPW. Three different states of the diodes configuration are investigated, where in each state multiple transmission zeros are produced in the frequency range from 1 GHz to 11 GHz. Slotline design equations are used to identify the resonant frequencies of the transmission zeros and validated using the magnetic field distribution inside the slot. In this work, the reconfigurability is first proven by means of open and short circuits in specific locations and then replaced by PIN diodes. Simulated and measured results are in good agreement. © 2010 Wiley Periodicals, Inc. Microwave Opt Technol Lett 52: 766–770, 2010; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.25003
Hot‐carrier reliability monitoring of DMG ISE SON MOSFET for improved analog performance
Authors: Kaur Ravneet , Chaujar Rishu , Saxena Manoj , Gupta R. S.
Published: January 2010

The hot‐carrier reliability, analog, and linearity characteristics of DMG ISE SON MOSFET have been discussed.The device reduces electron temperature by 35.85% in comparison to a non‐dual material gate (DMG) architecture showing its self‐heating resistant nature. The analog performance and linearity metrics—gm/IDS, Rout, VEA, and gm/gd and VIP2 and VIP3—have been studied facilitating the selection of bias point for improved RF/analog performance. © 2010 Wiley Periodicals, Inc. Microwave Opt Technol Lett 52: 770–775, 2010; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.25004
A new K‐band push‐push VCO using a miniaturized hairpin resonator
Authors: Lee Hyun‐Wook , Yoon Ki‐Cheol , Nam Hee , Eo Yun‐Seong , Lee Jong‐Chul
Published: January 2010

In this article, a K‐band push‐push Voltage Controlled Oscillator (VCO) is presented using a miniaturized hairpin resonator (MHR) with a higher loaded quality factor and the reduced circuit area within 50% compared to the conventional one at 9.2 GHz.The MHR combined with the GaAs MESFET varactor shows a tuning range of 140 MHz, and this voltage tunable MHR is used to compose a push‐push VCO. It provides the frequency tuning range of 71 MHz with flatness of +0.13 dB, which is increased by 31 MHz compared to the conventional VCO. The voltage controlled push‐push oscillator based on the series feedback topology is implemented on 0.54 mm‐thick Teflon substrate with a dielectric constant of 2.54. The measurement shows the output power of 1.18 dBm, the fundamental signal power suppression of −33 dBc, and phase noise performance of −86.78 dBc/Hz at 100 kHz offset. © 2010 Wiley Periodicals, Inc. Microwave Opt Technol Lett 52: 699–701, 2010; Published online in Wiley InterScience (www.interscience. wiley.com). DOI 10.1002/mop.25007
Automated design of microwave discrete tuning differential capacitance circuits in Si‐integrated technologies
Authors: Mendes Luís , Pires E.J. Solteiro , Vaz João C. , Rosário Maria J. , de Moura Oliveira P. B. , Machado J. A. Tenreiro
Published: January 2010

A genetic algorithm used to design radio‐frequency binary‐weighted differential switched capacitor arrays (RFDSCAs) is presented in this article. The algorithm provides a set of circuits all having the same maximum performance. This article also describes the design, implementation, and measurements results of a 0.25 μm BiCMOS 3‐bit RFDSCA. The experimental results show that the circuit presents the expected performance up to 40 GHz. The similarity between the evolutionary solutions, circuit simulations, and measured results indicates that the genetic synthesis method is a very useful tool for designing optimum performance RFDSCAs. © 2010 Wiley Periodicals, Inc. Microwave Opt Technol Lett 52: 629–634, 2010; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.25009
W‐band compact bandpass filters on thin‐film substrate
Authors: Yoo Chan‐Sei , Maeng Ji‐Min , Cheon Nam‐Cheol , Song Sangsub , Seo Kwang‐Seok
Published: January 2010

In this article, the miniaturized resonator and bandpass filter for W‐band application are suggested and evaluated on thin‐film substrate.In the meanwhile, the resonator using the loading capacitor with the electrical length of 2λg/9 and the other resonator using broadside coupled line structure of λg/9 are designed and applied for the compact filter evaluation. The filter using the capacitor‐loaded resonators with the dimension of 0.2 × 0.5 mm2shows the insertion loss of 2.1 dB at 94 GHz, and the return loss better than 10 dB at the frequencies between 91 and 98 GHz. For the filter using broadside coupled line resonators with the size of 0.33 × 0.24 mm2, the insertion loss is 2.3 dB at 92 GHz and the return loss is better than 10 dB in at the frequencies between 85 and 99 GHz. These filters show very compact dimensions retaining the filter performance commensurate with those of the filters in previous works. © 2010 Wiley Periodicals, Inc. Microwave Opt Technol Lett 52: 750–753, 2010; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.25011
Particle swarm optimization of L‐probe fed E‐shaped patch antenna using single‐objective function
Authors: Chung Kwok L. , Tam W. Y.
Published: January 2010

An application of particle swarm optimization (PSO) for wideband patch antenna design is presented in this article. A PSO kernel is built on a MATLAB‐driven MoM‐based EM simulator FEKO. The chosen antenna geometry in this study is the E‐shaped patch but excited by an L‐probe feed. Ten geometrical parameters are optimized simultaneously with the use of a single‐objective: impedance bandwidth broadening. The desired center frequency of this ceiling mounted WLAN (IEEE 802.11a/n) antenna is set at 5.5 GHz with butterfly beam operation. E‐shaped patch geometry of higher order mode is obtained from the PSO‐EM optimizer. The simulated results are verified by the experimental results that a ∼3.5 dBi gain at the elevation angles of ±36° and a >50% of 10‐dB return‐loss bandwidth are obtained at the price of high cross‐polarization levels. This suggests that a multiobjective particle swarm optimization should be used for the wideband antenna design in the future study. © 2010 Wiley Periodicals, Inc. Microwave Opt Technol Lett 52: 702–706, 2010; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.25016
High‐performance integrated passive technology by advanced SI‐GaAs‐based fabrication for RF and microwave applications
Authors: Wang Cong , Lee Ji‐Hoon , Kim Nam‐Young
Published: January 2010

In this letter, an advanced SI‐GaAs‐based manufacturing process is presented for creating high quality, cost effective, and compact size integrated passive devices. Through this advanced process, accurate thin film resistors, high Q spiral inductors, and high yield/breakdown voltage metal‐insulator‐metal capacitors can be successfully realized. © 2010 Wiley Periodicals, Inc. Microwave Opt Technol Lett 52: 618–623, 2010; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.25018
Modeling and simulation of a powerful terahertz generator based on Cherenkov superradiance
Authors: Zhang Hai , Wang Jianguo , Tian Chunming
Published: January 2010

In this article, the preliminary studies of coherent stimulated terahertz radiation from intense, subnanosecond electron beam are presented. The mechanism of terahertz pulse generation is associated with self‐bunching of the beam and slippage of the wave over the whole electron flow. This so‐called Cherenkov superradiance (SR) was used to propose a compact terahertz generator with high peak power. A large cross section (overmoded), slow wave structure was designed to support the high power handling capability, and the mode competition was avoided by operating the device in the surface wave status. With 2.5D particle‐in‐cell simulation, we investigated the “hot” characteristics of the proposed superradiant terahertz generator and found that the SR peak power could be further increased by optimizing the amplitude profile of electron pulse. © 2010 Wiley Periodicals, Inc. Microwave Opt Technol Lett 52: 657–662, 2010; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.25019
High resolution‐HMBC (HR‐HMBC), a new method for measuring heteronuclear long‐range coupling constants
Authors: Furihata Kazuo , Tashiro Mitsuru , Seto Haruo
Published: January 2010

A useful pulse sequence for measuring long‐range CH coupling constants (JCH) named high resolution‐HMBC (HR‐HMBC) has been developed. In this pulse sequence, the J‐scaling pulse [(nt1)/2180° (H/C) − (nt1)/2] is incorporated after the spin evolution period, and then followed by an 1H 180° pulse to reverse the magnetization of JCH couplings. As a result, splittings of the cross peaks due to the long‐range JCH are realigned with separations of nJCH along the F1 dimension, and thus even the small long‐range JCH values can easily be determined. The efficiency of measuring the long‐range JCH using the proposed pulse sequences has been demonstrated in application to the complicated natural product, portmicin. Copyright © 2010 John Wiley & Sons, Ltd.
Preparation of monodisperse poly(St‐co‐PETEA) microspheres by precipitation polymerization using ethanol as solvent
Authors: Jiang Hongyan , Chen Hou , Liang Ying , Liu Xin
Published: January 2010

Precipitation polymerization of styrene (St) was carried out with pentaerythritol tetraacrylate (PETEA) to produce monodisperse crosslinked microspheres. A much safer ethanol replaced acetonitrile as a solvent in precipitation polymerization of monodisperse crosslinked poly(St‐co‐PETEA) microspheres. Monodisperse crosslinked microspheres with high monomer conversion were achieved within 4 hr. Uniform and well‐separated monodisperse were obtained in ethanol when PETEA concentration varied from 30 vol% to 90 vol% and the particle diameter decreased from 0.75 to 0.58 µm. The particle yield increased from 36.51 to 64.38% by increase in the initiator loading from 1 to 8 wt%. No coagulum occurred between particles when the polymerization time varied from 2 to 10 hr. Copyright © 2010 John Wiley & Sons, Ltd.
Somatic mutations and losses of expression of microRNA regulation‐related genes AGO2 and TNRC6A in gastric and colorectal cancers
Authors: Kim Min S , Oh Ji E , Kim Yoo R , Park Sang W , Kang Mi R , Kim Sung S , Ahn Chang H , Yoo Nam J , Lee Sug H
Published: January 2010

Mounting evidence indicates that deregulation of microRNAs (miRNAs) are involved in development of many human diseases, including cancers. Regulation of miRNA is a complicated process and some components in the regulation are known to be altered in human cancers. Among the miRNA regulation‐related genes, we found that AGO1, AGO2, TNRC6A, TNRC6C, TARBP2 and EXPORTIN5 genes have mononucleotide repeats in their coding sequences. To see whether these genes are mutated in cancers with microsatellite instability (MSI), we analysed the mononucleotide repeats in 27 gastric cancers (GCs) with high MSI (MSI‐H), 18 GC with low MSI (MSI‐L), 45 GC with stable MSI (MSS), 41 colorectal cancers (CRCs) with MSI‐H, 14 CRCs with MSI‐L and 45 CRCs with stable MSI (MSS) by single‐strand conformation polymorphism (SSCP) analysis and DNA sequencing. We found AGO2, TNRC6A, TARBP2, TNRC6C and EXPORTIN5 mutations in 10, six, one, one and one cancer(s), respectively. They were detected in MSI‐H but not in MSI‐L or MSS cancers. The GCs and CRCs with MSI‐H harboured one or more mutations of the genes in 22% and 27%, respectively. We also analysed Ago2 and TNRC6A protein expressions in GCs and CRCs with MSI‐H. In cancers with MSI‐H, loss of Ago2 expression was observed in 40% of GCs and 35% of CRCs, while loss of TNRC6A was observed in 52% of the GCs and 54% of the CRCs. Our data indicate that frameshift mutations in AGO2 and TNRC6A and their losses of expression are common in GCs and CRCs with MSI‐H, and suggest that these alterations may contribute to the cancer development by deregulating miRNA regulation. Copyright © 2010 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.
Maternal plasma levels of follistatin‐related gene protein in the first trimester of pregnancies with Down syndrome
Authors: Miron Pierre , Lambert Jean , Marcil Anne , Cowans Nicholas J. , Stamatopoulou Anastasia , Spencer Kevin
Published: January 2010

Objective

To determine maternal plasma levels of follistatin‐related gene protein (FLRG) in the first trimester of pregnancy and assess its potential role as a marker for prenatal screening of Down syndrome.

Methods

Maternal plasma levels of FLRG were determined in 100 pregnant women with normal fetuses in their first trimester of pregnancy (i.e. 11th to 15th weeks). These results were compared with 20 cases with Down syndrome fetuses, taking into consideration clinical and demographic variables, such as maternal age, maternal weight, gestational age, smoking status and ethnicity.

Results

Maternal plasma median of FLRG in the normal population was 1.41 ng/mL with 95% confidence interval (CI) of 1.37–1.70 and interquartile range (IQR) of 0.88, during the 11th to 15th weeks of pregnancy. Maternal age and weight were the only variables significantly related to FLRG levels (p = 0.030 and 0.020, respectively). Only maternal and gestational ages were related to Down syndrome (p = 0.039 and 0.006, respectively). Maternal plasma levels of FLRG were not significantly different in the presence of Down syndrome fetuses compared to normal population (p = 0.63).

Conclusion

FLRG can be successfully detected in maternal plasma in the first trimester of pregnancy. However, its levels are not significantly altered in the presence of Down syndrome fetuses. Copyright © 2010 John Wiley & Sons, Ltd.
Identification of circulating placental mRNA in maternal blood of pregnancies affected with fetal congenital heart diseases at the second trimester of pregnancy: implications for early molecular screening
Authors: Arcelli Diego , Farina Antonio , Cappuzzello Claudia , Bresin Antonella , De Sanctis Paola , Perolo Antonella , Prandstraller Daniela , Valentini Davide , Zucchini Cinzia , Priori Silvia , Rizzo Nicola
Published: January 2010

Objective

To investigate whether a significantly aberrant expression of circulating placental mRNA genes related with cardiogenesis can be detected at the second trimester of pregnancy.

Methods

The study was performed in two stages. First stage (development model group): match of 14 placental tissues at delivery of fetuses with congenital heart disease versus 20 controls. Second stage (validation model group): mRNA amplification of abnormal expressed genes in maternal blood samples from 26 women bearing a fetus with a congenital heart disease matched with 28 controls.

Results

We identified four functional categories of genes possibly involved in abnormal heart development: cardiac morphogenesis: tenascin, thioredoxin, salvador homolog 1 protein; extracellular matrix (ECM) and valvular tissue biosynthesis; placental‐associated plasma protein, collagen, type I, alpha 2, fibulin‐1, heparanase, procollagen‐proline, 2‐oxoglutarate 4‐dioxygenase, alpha polypeptide II, Jumonji, AT rich interactive domain 1B RBP2‐like; normal contractile activity: actinin, alpha 4, fascin homolog 1, actin‐bundling protein; and congestive heart failure.

Conclusion

Altered placental genetic expression was found at term delivery in affected fetuses. The aberration was also confirmed in maternal blood at the second trimester of women bearing a fetus with congenital heart disease. Sensitivity for the most aberrant genes ranged between 42% and 95% at a false positive rate (FPR) of 10%. Copyright © 2010 John Wiley & Sons, Ltd.
Difference in nuchal translucency between monozygotic and dizygotic spontaneously conceived twins
Authors: Cheng Po‐Jen , Huang Shang‐Yu , Shaw Sheng‐Wen , Hsiao Ching‐Hwa , Kao Chuan‐Chi , Chueh Ho‐Yen , Hsieh T'sang‐T'ang
Published: January 2010

Objective

To assess nuchal translucency (NT) thickness and differences in inter‐twin NT thickness among naturally conceived monozygotic and dizygotic twins.

Methods

Enrolled women prospectively underwent NT measurement for both twins between 11 and 14 weeks of gestational age. NT thickness and inter‐twin NT difference were recorded and compared among dizygotic twins, monozygotic dichorionic twins, and monozygotic monochorionic twins.

Results

This study obtained analyzable data for 174 monozygotic twins and 107 dizygotic twins. Of the 174 monozygotic twins, 105 were monochorionic, and 69 were dichorionic. Monozygotic monochorionic twin pregnancies had a significantly higher mean fetal NT thickness (1.48 ± 0.62 mm) than either dizygotic twin pregnancies (1.34 ± 0.50 mm) or monozygotic dichorionic twin pregnancies (1.31 ± 0.48 mm). Mean inter‐twin NT difference was significantly lower in monozygotic dichorionic twin pregnancies (0.37 ± 0.19 mm) than in dizygotic twin pregnancies (0.57 ± 0.22 mm) or monochorionic twin pregnancies (0.65 ± 0.43 mm).Irrespective of twin zygosity, NT thickness and inter‐twin NT difference were larger in monochorionic twins than in dichorionic twins (1.48 ± 0.62 mm versus 1.33 ± 0.49 mm, and 0.65 ± 0.43 mm versus 0.49 ± 0.23 mm, respectively).

Conclusion

During first‐trimester ultrasonographic screening for Down syndrome, monochorionic twin pregnancies have the greatest NT thickness and monozygotic dichorionic twin pregnancies have the lowest inter‐twin NT difference. Copyright © 2010 John Wiley & Sons, Ltd.
Chitosan, itaconic acid and poly(vinyl alcohol) hybrid polymer networks of high degree of swelling and good mechanical strength
Authors: Milosavljević Nedeljko B , Kljajević Ljiljana M , Popović Ivanka G , Filipović Jovanka M , Kalagasidis Krušić Melina T
Published: January 2010

Chitosan is a biodegradable, non‐toxic, biocompatible polymer convenient for use in drug delivery. In this study, hybrid polymeric networks (HPNs) based on chitosan, itaconic acid and poly(vinyl alcohol) (PVA) were prepared and characterized. Chitosan was dissolved in itaconic acid in order to obtain ionic crosslinking with the dicarboxylic acid. In the second step, this chitosan/itaconic acid network was mixed with PVA and chemically crosslinked with glutaraldehyde. The chitosan/itaconic acid ratio was kept constant, while the concentrations of PVA and glutaraldehyde were varied. All samples were characterized using swelling studies, dynamic mechanical analysis, Fourier transform infrared spectroscopy, differential scanning calorimetry, thermogravimetric analysis, X‐ray diffraction and scanning electron microscopy. The equilibrium degrees of swelling obtained for the HPNs were higher than most of the values reported for chitosan hydrogels obtained by dissolving chitosan in acetic acid or HCl aqueous solutions. This method of synthesis also resulted in hydrogels with better mechanical properties and thermal stability. By changing the PVA content and the degree of crosslinking, it is possible to finely tune the properties of the HPNs, which could make them suitable as potential matrices in controlled drug delivery. Copyright © 2010 Society of Chemical Industry
Nanofiber formation of amphiphilic cyclic tri‐β‐peptide
Authors: Ishihara Yusuke , Kimura Shunsaku
Published: January 2010

A novel amphiphilic cyclic peptide composed of two β‐glucosamino acids and one trans‐2‐aminocyclohexylcarboxylic acid was synthesized and investigated on assembly formation. The cyclic tri‐β‐peptide was self‐assembled into rodlike crystals or nanofibers depending on preparative conditions. The rodlike crystals showed a layer spacing of 4.8 Å along the long axis, and columnar spacings of 10.8 and 21.5 Å by electron diffraction analysis along the short axis. The former confirms the columnar structure upon molecular stacking, and the latter indicates triple bundle formation of the columnar assemblies. Fourier transform infrared (FT‐IR) measurement of the fibrous assembly showed formation of homogeneous hydrogen bonds among amide groups, also supporting the molecular stacking of cyclic β‐peptides. Straight nanofibers with uniform diameter were also uniquely obtained. Copyright © 2010 European Peptide Society and John Wiley & Sons, Ltd.
Carbon nanostructures from Fe–C nanocomposites by activated CVD methods
Authors: Fleaca Claudiu , Morjan Ion , Alexandrescu Rodica , Dumitrache Florian , Soare Iuliana , Gavrila‐Florescu Lavinia , Normand François Le , Faerber Jaques
Published: January 2010

Iron‐based core‐shell nanoparticles can present interesting catalytic properties for the growth of carbon nanostructures. We report the synthesis of various carbon nanostructures using activated chemical vapour deposition methods. These structures were analysed by Scanning Electon Microscopy (SEM) and Raman spectroscopy. Laser pyrolysis technique was used for synthesis of less than 10 nm diameter Fe‐C core‐shell catalyst nanoparticles. Acetone suspensions of Fe‐C nanoparticles were drop‐casted or spin coated onto Si(100) substrates. The consequence of hydrogen selective etching of these nanocomposites at 550 °C, followed by a treatment with a mixture of H2 and C2H2 at 700 °C (both in the presence of hot filaments) was the growth of corrugated ribbons and decorated or distorted carbon nanotubes/nanofibers. Round agglomerate nanoparticles and long and very thin nanotubes were observed on the substrates edges (protected from direct etching). By adding in similar conditions a glow discharge plasma to hot filaments, the resulted deposits contain oriented nanotubes. Due to the implication of the electric field, the presence of both plasma and hot wires seems to significantly change the specific growth conditions of carbon nanostructures towards those resulted when only incandescent filaments were used (© 2010 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)