bluuebunny/crossref_metadata_2025 huggingface dataset:
A bend loss–based singlemode fiber microdisplacement sensor
Authors: Wang Pengfei , Semenova Yuliya , Wu Qiang , Farrell Gerald
Published: July 2010

An all‐fiber displacement sensor with a simple configuration is proposed and investigated theoretically and experimentally. The proposed fiber displacement sensor consists of a half‐loop structure of high‐bend loss singlemode fiber‐1060XP. A ratiometric power measurement system for interrogating the proposed sensor is also presented. By measuring the change in ratio of bend loss in the ratiometric measurement system, a change in displacement can be measured assuming the ratiometric system is calibrated. The proposed macrobending fiber–based displacement sensor achieves a competitive resolution of circa 0.3 μm and also benefits from simplicity compared with conventional fiber Bragg grating–based displacement sensor. The displacement sensor is sensitive to temperature and an experimental investigation of this sensitivity is presented. It is found that the ratio response has a linear variation with temperature; therefore, temperature dependence can be mitigated by a suitable correction process. © 2010 Wiley Periodicals, Inc. Microwave Opt Technol Lett 52:2231–2235, 2010; Published online in Wiley InterScience (www.interscience. wiley.com). DOI 10.1002/mop.25446
Improved peak power method for measuring frequency responses of photodetectors in a self‐heterodyne system
Authors: Xian Wang Li , Hua Zhu Ning , Hong Ke Jian , Li Wei , Fu Chen Shuo , Xie Liang
Published: July 2010

An improved peak power method for measuring frequency responses of photodetectors in a self‐heterodyne system consisting of a distributed Bragg reflector laser is proposed.The time‐resolved spectrum technique is used to measure the peak power of the beat signal and the intrinsic linewidth of beat signal for calibration. The experimental results show that the impact of the thermal‐induced frequency drift, which is the main reason for producing an error in measurement by conventional peak power method and spectrum power method, can be removed. © 2010 Wiley Periodicals, Inc. Microwave Opt Technol Lett 52:2199–2203, 2010; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.25448
A meandering dual‐mode bandpass filter with rectangular‐loop perturbation
Authors: Chu Rui , Mao Jun‐Fa , Zhou Liang
Published: July 2010

A dual‐mode bandpass filter is proposed that is composed of a meandering resonator and a small rectangular loop for the purpose of perturbation.Both the length and width of the rectangular loop could control the dual‐mode resonant frequencies. A prototype filter is designed and fabricated with a center frequency of 2.45 GHz. The measured fractional bandwidth is 10.98%, insertion loss is 0.8 dB, and return loss is over 15 dB, which are in good agreement with the simulated results. © 2010 Wiley Periodicals, Inc. Microwave Opt Technol Lett 52:2356–2359, 2010; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.25454
Harmonic‐rejected compact bandpass filter using dual‐mode microstrip resonator with additional open stub
Authors: Yun Tae‐Soon , Nam Hee , Lee Byungje , Choi Jin‐Joo , Kim Jin‐Young , Lee Jong‐Chul
Published: July 2010

In this article, a compact dual‐mode λg/2 bandpass filter with the characteristic of harmonic rejection is designed and implemented.The second and third harmonics of the suggested bandpass filter are rejected by using the additional open stubs of the T‐type equivalent circuit for the quarter wavelength line. Also, the J‐inverter is investigated as functions of the impedance and electrical length of the open stub of dual‐mode λg/2 resonator. From the results, the lower impedance of open stub of dual‐mode λg/2 resonator is better for the good performance of the dual‐mode λg/2 bandpass filter. The harmonic‐rejected dual‐mode λg/2 bandpass filter shows the characteristic of suppression of harmonics until 8 GHz and the insertion and return losses of 0.96 and 18.89 dB, respectively, at the center frequency of 2.43 GHz. © 2010 Wiley Periodicals, Inc. Microwave Opt Technol Lett 52:2288–2291, 2010; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.25457
Design of a new meander Archimedean spiral antenna
Authors: Wang Ya‐Wei , Wang Guang‐Ming , Zeng Hui‐Yong
Published: July 2010

This article introduces a compact sine wave meander Archimedean spiral antenna designed by adding sinusoidal function to Archimedean function.Results simulated and measured show that the proposed antenna possesses fine wideband properties. The measured return loss is less than −10 dB in the frequency range of 1.625–10 GHz and the axial ratio is less than 3 dB within the design frequency range (1.63–10 GHz). Compared to a typical Archimedean spiral antenna in the same operating band, the antenna presented in this article has a 63.6% reduction in area. © 2010 Wiley Periodicals, Inc. Microwave Opt Technol Lett 52:2384–2387, 2010; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.25464
Colpitts VCO with gate‐series high‐quality factor LC resonator
Authors: Jang Sheng‐Lyang , Chou Li‐Te , Chang Chia‐Wei
Published: July 2010

A new differential voltage‐controlled oscillator (VCO) is designed and implemented in a 0.13‐μm CMOS 1P8M process. The designed circuit topology is ann‐core LC‐tank VCO with an LC resonator. At the supply voltage of 1.1 V, the output phase noise of the VCO is −113.8 dBc/Hz at 1‐MHz offset frequency from the carrier frequency of 11.73 GHz and the figure of merit is −192.01 dBc/Hz. The core power consumption is 1.83 mW. Tuning range is 1.47 GHz from 10.66 to 12.13 GHz, while the control voltage was tuned from 0 to 1.2 V. © 2010 Wiley Periodicals, Inc. Microwave Opt Technol Lett 52:2170–2173, 2010; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.25466
Generalized negative‐refractive index transmission line based on defected ground structure
Authors: Ryu Young‐Ho , Park Jae‐hyun , Lee Jeong‐Hae , Tae Heung‐Sik
Published: July 2010

The planar generalized negative‐refractive index transmission line (G‐NRI TL) is proposed using only distributed structures, such as defected ground structure, stub with rectangular patch, wire‐bonded interdigital capacitor, and short stub.The characteristics, such as dispersion relation and frequency response of the G‐NRI TL are analyzed by circuit analysis, full wave simulation, and measurement. The results show a good agreement. © 2010 Wiley Periodicals, Inc. Microwave Opt Technol Lett 52:2223–2225, 2010; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.25467
Performance evaluation of three basic antennas in chip packages for 60‐GHz radios
Authors: Sun M. , Zhang Y. P. , Chua K. M. , Wai L. L. , Liu D.
Published: July 2010

This article presents the performance evaluation of three basic antennas in chip packages in low‐temperature cofired ceramic (LTCC) technology for 60‐GHz radios. The three basic antennas are dipole, patch, and slot. They are integrated in three chip packages of the same design and size 12.5 × 8 × 1.265 mm3and are tested with a probe‐based measurement system in an anechoic chamber, respectively. Measured impedance and radiation results are compared and discussed, showing that they all achieve acceptable antenna performance in the 60‐GHz band from 57 to 64 GHz. Hence, it can be concluded that the integration of a basic antenna in a chip package in LTCC technology is feasible for short‐range high‐speed 60‐GHz wireless communications. © 2010 Wiley Periodicals, Inc. Microwave Opt Technol Lett 52:2359–2363, 2010; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.25471
Optimal shunt inductance sizing for high pulse fidelity wideband amplifiers
Authors: Amoroso Francesco Antonio , Pugliese Andrea , Cappuccino Gregorio
Published: July 2010

A new design approach for wideband amplifiers with inductive shunt peaking is presented.An accurate circuit model and a well‐defined rule to size the shunt inductance are introduced to control the oscillations in the amplifier step response by fixing the desired damping factor of the amplifier poles. The proposed strategy guarantees systematic settling time minimization for a given power dissipation and is very suitable to design efficient amplifiers for wideband applications demanding high pulse fidelity. Design examples in a commercial 0.13‐μm CMOS technology are also presented. Simulation results show the effectiveness of the method. © 2010 Wiley Periodicals, Inc. Microwave Opt Technol Lett 52:2324–2327, 2010; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.25473
A compact butler matrix for WLAN application
Authors: Maddah‐Ali Mohsen , Forooraghi Keyvan
Published: July 2010

In this article, a compact butler matrix for wireless communications is designed and implemented at 2.4 GHz using defected ground structures (DGS).The butler matrix consists of a 3‐dB coupler, crossover (0‐dB coupler), and phase shifter. The 3‐dB coupler and crossover are compacted using T‐model of transmission line and DGS. The size of proposed butler matrix is about 35% of a conventional matrix. To verify simulation results, designed matrix has been implanted and measured. Fortunately, there is very good agreement between simulation results and measured results. © 2010 Wiley Periodicals, Inc. Microwave Opt Technol Lett 52:2294–2298, 2010; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.25474
Horizontal five‐arm folded dipole over metal screening plane for UHF RFID of dielectric objects
Authors: Švanda Milan , Polívka Milan
Published: July 2010

The article is concerned with the extremely low‐profile foam dielectric five‐arm folded dipole antenna, which was developed and manufactured. The aforementioned antenna is situated on the metal screening plane and is used for UHF RFID of dielectric objects. It is designed with a complex input impedance Zin = 22 + j195 Ω at 866 MHz. Its efficiency was evaluated by Wheeler cap method with and without enclosed a human body phantom, it accounts for ∼40%, irrespective of whether the phantom is enclosed or not. The preliminary test of the identification range in buildings corridor was performed. The identification range reaches as far as 15.8 m. © 2010 Wiley Periodicals, Inc. Microwave Opt Technol Lett 52:2291–2294, 2010; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.25475
Design of an ultra‐wideband MIMO antenna for PDA applications
Authors: Lee Jaewon , Hong Seokjin , Choi Jaehoon
Published: July 2010

A low‐profile, ultra‐wideband (UWB), multi‐input multi‐output (MIMO) antenna for a personal digital assistant application is proposed.To improve the impedance bandwidth, a 2 mm × 1 mm connecting strip is used on each antenna element. The isolation characteristic between the two antenna elements is improved by inserting two T‐shaped stubs. The optimized design parameters were obtained through parametric analysis. The designed antenna has a 10‐dB return loss bandwidth of 9 GHz (2.2–11.2 GHz) covering the WiBro, Bluetooth, WiMax, S‐DMB, and UWB frequency bands, with an isolation characteristic below −20 dB over the operating frequency. Additionally, the envelope correlation coefficient is less than 0.12. © 2010 Wiley Periodicals, Inc. Microwave Opt Technol Lett 52:2165–2170, 2010; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.25478
Low cost 60‐GHz microstrip bandpass filter with stub‐loaded anticoupled line
Authors: Wong Sai Wai , Chen Zhi Ning , Qing Xianming
Published: July 2010

A 60‐GHz microstrip bandpass filter with stub‐loaded anticoupled line is presented in this article. First, a dual‐mode bandpass filter is discussed, which has two transmission zeros at the lower and upper cut‐off frequencies for a sharp rejection skirt. The lower transmission zero near cut‐off frequency is created by the anticoupled line section, whereas the stub‐loaded section provides another transmission zero at the upper cut‐off frequency. Meanwhile, the coupling effect of the stub‐loaded section is eliminated to improve the suppression in the upper‐stopband. Then, a half‐wave strip resonator is inserted into the anticoupled lines to achieve a 3‐pole bandpass filter with sharper rejection and wider bandwidth. Finally, a prototype is designed and fabricated on a single‐layered Roger4003C substrate to experimentally validate the in‐band and out‐of‐band performances of the proposed filter over an unlicensed 60‐GHz ISM band of 57–64 GHz. The measurement shows that the suppressions in lower and upper bands are, respectively, 20 dB and 25 dB, and the insertion loss is 1.1 dB at 60 GHz. © 2010 Wiley Periodicals, Inc. Microwave Opt Technol Lett 52:2375–2378, 2010; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.25479
Design of dual‐mode bandpass filter using SRR structure
Authors: Zhou Ming , Tong Chuang‐ming , Fu Shu‐hong , Wu Li‐nan
Published: July 2010

This article presented a novel bandpass microwave filter, which is synthesized split‐ring resonators (SRR) with dual‐mode filters techniques. The structure of this filter is simple and compact size, low insertion loss, and higher capability of power handling. With the structure of SRR and the method of straightway connect triangular resonator, It has remarkable advantages, such as lower ripple level, wider passband and higher selectivity. The effects of varying the parameters of the filter have been studied. The structure was fabricated and measured experimental results agree with the simulation results very well. © 2010 Wiley Periodicals, Inc. Microwave Opt Technol Lett 52:2372–2375, 2010; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.25480
Experimental phase plate employing a phase modulated active frequency selective surface
Authors: Taylor P. S. , Parker E.A. , Batchelor J. C.
Published: July 2010

A novel method employing a phase modulated frequency selective surface (FSS) to improve the wireless communications coverage of enclosed spaces in the built environment through the filling of black spots is described. The design and fabrication of a phase modulated FSS are discussed, together with some initial measurements and results. © 2010 Wiley Periodicals, Inc. Microwave Opt Technol Lett 52:2300–2302, 2010; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.25484
Compact dual‐band bandpass filter using slot‐line resonator
Authors: Bao Zhi‐Hua , Chen Jian‐Xin , Tang Hui , Zhou Li‐Heng
Published: July 2010

This letter presents a novel compact dual‐band bandpass filter (BPF), which consists of two pairs of half‐guided wavelength slot‐line resonators. The two pairs of resonators, operating at different frequencies, generate two passbands for the proposed BPF by utilizing a novel coupling scheme. Tight coupling between the two resonators in each of the pairs can be simultaneously achieved, and the interaction between the two pairs is negligible. Thus the operation frequencies of the two passbands can be controlled independently. Several attenuation poles are created to enhance the selectivity of the proposed filter. The simulated and measured results are presented, showing good agreement. © 2010 Wiley Periodicals, Inc. Microwave Opt Technol Lett 52:2299–2300, 2010; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.25485
Terahertz wave modulator based on optically controlled photonic crystal slab
Authors: Li Jiu‐sheng , Tao Gui‐sheng
Published: July 2010

We studied the design and characterization of an optically controlled terahertz (THz) wave modulator based on silicon photonic crystal slab, which is made from a high‐resistivity Si with triangular lattice and a line defect formed by removing a single row of air holes along Γ‐K direction. A modulated semiconductor laser with 808‐nm wavelength is used to illuminate the line defect of the photonic crystal. The interaction between the bandgap shift and THz wave is strengthened and yields an appreciable modulation of the THz output beam for optical pump. Experimental results show that the presented THz wave modulator has modulation speed of 0.8 Kb/s by modulated semiconductor laser excitation 150‐mw average power at 808 nm. © 2010 Wiley Periodicals, Inc. Microwave Opt Technol Lett 52:2226–2227, 2010; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.25489
Measurement non‐invariance of DSM‐IV narcissistic personality disorder criteria across age and sex in a population‐based sample of Norwegian twins
Authors: Kubarych Thomas S. , Aggen Steven H. , Kendler Kenneth S. , Torgersen Sven , Reichborn‐Kjennerud Ted , Neale Michael C.
Published: July 2010

We investigated measurement non‐invariance of DSM‐IV narcissistic personality disorder (NPD) criteria across age and sex in a population‐based cohort sample of 2794 Norwegian twins. Age had a statistically significant effect on the factor mean for NPD. Sex had a statistically significant effect on the factor mean and variance. Controlling for these factor level effects, item‐level analysis indicated that the criteria were functioning differently across age and sex. After correcting for measurement differences at the item level, the latent factor mean effect for age was no longer statistically significant. The mean difference for sex remained statistically significant after correcting for item threshold effects. The results indicate that DSM‐IV NPD criteria perform differently in males and females and across age. Differences in diagnostic rates across groups may not be valid without correcting for measurement non‐invariance.
In‐Line Monitoring of Vinyl Chloride Suspension Polymerization with Near Infrared Spectroscopy, 2 ‐ Design of an Advanced Control Strategy
Authors: de Faria João Miguel , Machado Fabricio , Lima Enrique Luis , Pinto José Carlos
Published: July 2010

Near infrared spectroscopy (NIRS) may constitute a powerful tool for in‐line monitoring of morphological properties of PVC particles in suspension polymerizations. It is shown that dynamic trajectories of morphological properties, as predicted with NIR‐based calibration models, change smoothly along the batch; thus, these trajectories can be used as references for process monitoring and control. It is also shown that modification of operation variables during the batch leads to modification of the final morphological properties of the powder. This indicates that the morphology of PVC grains can be manipulated along the batch and that advanced NIR‐based control procedures can be implemented for control of the morphological properties of PVC resins, as illustrated through simulation.

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Minimum envelope roughness pulse design for reduced amplifier distortion in parallel excitation
Authors: Grissom William A. , Kerr Adam B. , Stang Pascal , Scott Greig C. , Pauly John M.
Published: July 2010

Parallel excitation uses multiple transmit channels and coils, each driven by independent waveforms, to afford the pulse designer an additional spatial encoding mechanism that complements gradient encoding. In contrast to parallel reception, parallel excitation requires individual power amplifiers for each transmit channel, which can be cost prohibitive. Several groups have explored the use of low‐cost power amplifiers for parallel excitation; however, such amplifiers commonly exhibit nonlinear memory effects that distort radio frequency pulses. This is especially true for pulses with rapidly varying envelopes, which are common in parallel excitation. To overcome this problem, we introduce a technique for parallel excitation pulse design that yields pulses with smoother envelopes. We demonstrate experimentally that pulses designed with the new technique suffer less amplifier distortion than unregularized pulses and pulses designed with conventional regularization. Magn Reson Med, 2010. © 2010 Wiley‐Liss, Inc.
Rapid T1 mapping of mouse myocardium with saturation recovery look‐locker method
Authors: Li Wen , Griswold Mark , Yu Xin
Published: July 2010

Dynamic contrast‐enhanced MRI using gadolinium or manganese provides unique characterization of myocardium and its pathology. In this study, an electrocardiography (ECG) triggered saturation recovery Look‐Locker method was developed and validated for fast cardiac T1 mapping in small animal models. By sampling the initial portion of the longitudinal magnetization recovery curve, high temporal resolution (∼3 min) can be achieved at a high spatial resolution (195 × 390 μm2) in mouse heart without the aid of parallel imaging or echo‐planar imaging. Validation studies were performed both in vitro on a phantom and in vivo on C57BL/6 mice (n = 6). Our results showed a strong agreement between T1 measured by saturation recovery Look‐Locker and by the standard saturation recovery method in vitro or inversion recovery Look‐Locker in vivo. The utility of saturation recovery Look‐Locker in dynamic contrast‐enhanced MRI studies was demonstrated in manganese‐enhanced MRI experiments in mice. Our results suggest that saturation recovery Look‐Locker can provide rapid and accurate cardiac T1 mapping for studies using small animal models. Magn Reson Med, 2010. © 2010 Wiley‐Liss, Inc.
Determination of three‐dimensional ventricular strain distributions in gene‐targeted mice using tagged MRI
Authors: Chuang Joyce S. , Zemljic‐Harpf Alice , Ross Robert S. , Frank Lawrence R. , McCulloch Andrew D. , Omens Jeffrey H.
Published: July 2010

A model‐based method for calculating three‐dimensional (3D) cardiac wall strain distributions in the mouse has been developed and tested in a genetically engineered mouse model of dilated cardiomyopathy. Data from MR tagging and harmonic phase (HARP) tracking were used to measure material point displacements, and 3D Lagrangian strains were calculated throughout the entire left ventricle (LV) with a deformable parametric model. A mouse model where cardiomyocytes are specifically made deficient in vinculin (VclKO) were compared to wild‐type (WT) littermates. 3D strain analysis revealed differences in LV wall mechanics between WT and VclKO mice at 8 weeks of age when systolic function had just begun to decline. Most notably, end‐systolic radial strain and torsional shear were reduced in VclKO hearts which contributed to regional mechanical dysfunction. This study demonstrates the feasibility of using MRI tagging methods to detect alterations in 3D myocardial strain distributions in genetically engineered mouse models of cardiovascular disease. Magn Reson Med, 2010. © 2010 Wiley‐Liss, Inc.
Was Wacker Chemie leistungsfähig macht
Authors: Schorsch Gilbert
Published: July 2010

Gilbert Schorsch

Der Machtzuwachs der Familie Wacker in der Geschäftsführung fällt mit steigenden Betriebsergebnissen zusammen. Für den Erfolg des Unternehmens gibt es mehrere Gründe wie komplexe Prozesse zu nutzen sowie Marktanforderungen und Partner einzubeziehen.
Die chemische Industrie als Schulsponsor
Authors: Neubauer Uta
Published: July 2010

Uta Neubauer

Um Schüler für Chemie zu begeistern, spenden Chemieunternehmen und ‐verbände Experimentiersets. Damit verbinden sie oft Eigenwerbung. Trotzdem dürfen Lehrer die Unterstützung getrost annehmen, schließlich bleibt die Unterrichtsgestaltung in ihrer Hand.
Schalter und Regulatoren der Proteinsynthese
Authors: Engels Joachim , Jäschke Andres
Published: July 2010

Joachim Engels, Andres Jäschke

Die biologischen Funktionen von Ribonukleinsäuren gehen über die traditionell bekannten Rollen hinaus. RNAs sind mehr als Informationsüberträger, Ribosomenkomponente und Adapter für die Proteinbiosynthese. Die Erkenntnis, wie weitgehend kleine RNAs die Genexpression schalten und regulieren, kam dennoch überraschend.
Cranial traumatic injuries caused by weapons in Tokugawa Japan
Authors: Nagaoka Tomohito
Published: July 2010

Weapon‐related traumas on human skeletons provide us with direct evidence of violence in archaeological and forensic contexts. The purposes of this study are to describe the weapon‐related traumas on Edo‐period (AD 17th–19th centuries) human skeletons from the Hitotsubashi site (Tokyo, Japan), to examine their presence, distribution and variability, and finally to better understand violence during that period. The specimens observed here are two adult males exhibiting eight traumas: five sharp‐force traumas caused by edged blades (62.5%) and three blunt‐force traumas with radiating fractures (37.5%). The frequency of individuals with traumas is 1.0% out of 207 individuals and 3.3% out of 64 adult males. The traumas found on the Hitotsubashi crania are distinguishable from those on the medieval crania in terms of low traumatic frequency. These observations shed new light on the life and death situations of the Edo inhabitants from osteoarchaeological perspectives. Copyright © 2010 John Wiley & Sons, Ltd.
The role of the RNA‐binding protein Sam68 in mammary tumourigenesis
Authors: Elliott David J , Rajan Prabhakar
Published: July 2010

The RNA binding protein Sam68 (Src‐associated in mitosis 68 kD) is implicated in cell signalling, transcriptional regulation, pre‐mRNA splicing, and is overexpressed and/or hyperphosphorylated in breast, prostate, and renal cancers. Sam68 has roles in normal breast development; however, a study by Song et al published in this issue of The Journal of Pathology reports overexpression of nuclear and cytoplasmic Sam68 protein in a large cohort of clinical breast tumours, implicating Sam68 as a potential prognostic indicator and target for therapy. In breast cancer cells, nuclear Sam68 protein might affect the expression of cancer‐relevant genes and/or modulate exon splicing patterns in a dose‐dependent manner. Sam68‐regulated expression of alternative transcripts may help drive mammary tumourigenesis. The high levels of cytoplasmic Sam68 protein observed in breast cancer cells could also impact on cellular signalling pathways important for mammary tumour cell biology. Copyright © 2010 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.

Invited Commentary for Song L et al. Sam68 up‐regulation correlates with, and its down‐regulation inhibits, proliferation and tumourigenicity of breast cancer cells. Journal of Pathology, http://dx.doi.org/10.1002/path.2751
Quercetin activates AMP‐activated protein kinase by reducing PP2C expression protecting old mouse brain against high cholesterol‐induced neurotoxicity
Authors: Lu Jun , Wu Dong‐mei , Zheng Yuan‐lin , Hu Bin , Zhang Zi‐feng , Shan Qun , Zheng Zi‐hui , Liu Chan‐min , Wang Yong‐jian
Published: July 2010

It is known that a high‐cholesterol diet induces oxidative stress, inflammatory response, and beta‐amyloid (Aβ) accumulation in mouse brain, resulting in neurodegenerative changes. Quercetin, a naturally occurring flavonoid, has been reported to possess numerous biological activities beneficial to health. Our previous studies have demonstrated that quercetin protects mouse brain against D‐galactose‐induced oxidative damage. Against this background, we evaluated the effect of quercetin on high‐cholesterol‐induced neurotoxicity in old mice and explored its potential mechanism. Our results showed that oral administration of quercetin significantly improved the behavioural performance of high‐cholesterol‐fed old mice in both a step‐through test and the Morris water maze task. This is at least in part caused by decreasing ROS and protein carbonyl levels and restoring CuZn superoxide dismutase (Cu, Zn‐SOD) activity. Furthermore, quercetin also significantly activated the AMP‐activated protein kinase (AMPK) via down‐regulation of protein phosphatase 2C (PP2C), which reduced the integral optical density (IOD) of activated microglia cells and CD11b expression, down‐regulated iNOS and cyclooxygenase‐2 (COX‐2) expression, and decreased IL‐1β, IL‐6, and TNF‐α expression in the brains of high‐cholesterol‐fed old mice through the suppression of NF‐κB p65 nuclear translocation. Moreover, AMPK activation significantly increased 3‐hydroxy‐3‐methylglutaryl‐coenzyme A (HMG‐CoA) reductase and acetyl‐CoA carboxylase (ACC) phosphorylation and reduced fatty acid synthase (FAS) expression in the brains of high‐cholesterol‐fed old mice, which reduced cholesterol levels, down‐regulated cholesterol 24‐hydroxylase (CYP46A1) and β‐amyloid converting enzyme 1 (BACE1) expression, decreased eukaryotic translation initiation factor 2α (eIF2α) phosphorylation, and lowered Aβ deposits. However, the neuroprotective effect of quercetin was weakened by intraperitoneal injection of compound C, an AMPK inhibitor. These results suggest that AMPK activated by quercetin may be a potential target to enhance the resistance of neurons to age‐related diseases. Copyright © 2010 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.
Filamentary and Homogeneous Modes of Dielectric Barrier Discharge (DBD) in Air: Investigation through Plasma Characterization and Simulation of Surface Irradiation
Authors: Rajasekaran Priyadarshini , Mertmann Philipp , Bibinov Nikita , Wandke Dirk , Viöl Wolfgang , Awakowicz Peter
Published: July 2010

The reported dielectric barrier discharge (DBD) source comprises of a ceramic‐covered copper electrode, and plasma can be ignited in ambient air with grounded ‘opposite’ electrodes or with objects of high capacitance (e.g., human body), when breakdown conditions are satisfied. Filamentary plasma mode is observed when the same source is operated using grounded opposite electrodes like aluminium plate and phosphate buffered saline solution, and a homogeneous plasma mode when operated on glass. When the source is applied on human body, both homogeneous and filamentary discharges occur simultaneously which cannot be resolved into two separate discharges. Here, we report the characterization of filamentary and homogeneous modes of DBD plasma source using the above mentioned grounded electrodes, by applying optical emission spectroscopy, microphotography and numerical simulation. Averaged plasma parameters like electron velocity distribution function and electron density are determined. Fluxes of nitric oxide, ozone and photons reaching the treated surface are simulated. These fluxes obtained in different discharge modes namely, single‐filamentary discharge (discharge ignited in same position), stochastical filamentary discharge and homogeneous discharge are compared to identify their applications in human skin treatment. It is concluded that the fluxes of photons and chemically‐active particles in the single filamentary mode are the highest but the treated surface area is very small. For treating larger area, the homogeneous DBD is more effective than stochastical filamentary discharge.

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Association of airway cathepsin B and S with inflammation in cystic fibrosis
Authors: Martin S.L. , Moffitt K.L. , McDowell A. , Greenan C. , Bright‐Thomas R.J. , Jones A.M. , Webb A.K. , Elborn J.S.
Published: July 2010

Irreversible tissue damage within the cystic fibrosis (CF) lung is mediated by proteolytic enzymes during an inflammatory response. Serine proteinases, in particular neutrophil elastase (NE), have been implicated however, members of the cysteine proteinase family may also be involved. The aim of this study was to determine cathepsin B and S levels in cystic fibrosis (CF) sputum and to assess any relationship to recognized markers of inflammation such as sputum NE, interleukin‐8 (IL‐8), tumor necrosis factor alpha (TNF‐α), urine TNF receptor 1 (TNFr1), plasma IL‐6, and serum C‐reactive protein (CRP). Proteinase activities were measured in the sputum of 36 clinically stable CF patients using spectrophotometric and fluorogenic assays. Immunoblots were also used to confirm enzyme activity data. All other parameters were measured by ELISA. Patients had a mean age of 27.2 (8.2) years, FEV. of 1.6 (0.79) L and BMI of 20.7 (2.8). Both cathepsin B and S activities were detected in all samples, with mean concentrations of 18.0 (13.5) µg/ml and 1.6 (0.88) µg/ml, respectively and were found to correlate not only with each other but with NE, TNF‐α and IL‐8 (in all cases . < 0.05). Airway cathepsin B further correlated with circulatory IL‐6 and CRP however, no relationship for either cathepsin was observed with urine TNFr1. This data indicates that cathepsin B and S may have important roles in the pathophysiology of CF lung disease and could have potential as markers of inflammation in future studies. Pediatr. Pulmonol. 2010; 45:860–868. © 2010 Wiley‐Liss, Inc.
Chronic eosinophilic pneumonia with mucous plugs in a child
Authors: Cakir Erkan , Aksoy Ferda , Çakır Fatma Betül , Ertem Temel
Published: July 2010

Chronic eosinophilic pneumonia is a rare cause of chronic lung disease in children. A 7‐year‐old girl who attended our clinics with cough and sputum lasting for 5 years, has been evaluated for bilateral alveolar infiltration and ground‐glass opacities. Peripheral eosinophilia was detected in total cell blood count. Flexible bronchoscopy showed mucous plugs. Bronchoalveolar lavage fluid and cell block of mucous plugs determined hypereosinophilia. Chronic eosinophilic pneumonia was confirmed after the elimination of other eosinophilic lung diseases and the case was accepted to be idiopathic. She showed a dramatic response to oral corticosteroids. This is the first reported case of chronic eosinophilic pneumonia presenting with mucous plugs in children described to date in the literature. Pediatr Pulmonol. 2010; 45:1040–1042. © 2010 Wiley‐Liss, Inc.
Antibody responses to prostate‐associated antigens in patients with prostatitis and prostate cancer
Authors: Maricque Brett B. , Eickhoff Jens C. , McNeel Douglas G.
Published: July 2010

BACKGROUND

An important focus of tumor immunotherapy has been the identification of appropriate antigenic targets. Serum‐based screening approaches have led to the discovery of hundreds of tumor‐associated antigens recognized by IgG. Our efforts to identify immunologically recognized proteins in prostate cancer have yielded a multitude of antigens; however, prioritizing these antigens as targets for evaluation in immunotherapies has been challenging. In this report, we set out to determine whether the evaluation of multiple antigenic targets would allow the identification of a subset of antigens that are common immunologic targets in patients with prostate cancer.

METHODS

Using a phage immunoblot approach, we evaluated IgG responses in patients with prostate cancer (n = 126), patients with chronic prostatitis (n = 45), and men without prostate disease (n = 53).

RESULTS

We found that patients with prostate cancer or prostatitis have IgG specific for multiple common antigens. A subset of 23 proteins was identified to which IgG were detected in 38% of patients with prostate cancer and 33% patients with prostatitis versus 6% of controls (P < 0.001 andP = 0.003, respectively). Responses to multiple members were not higher in patients with advanced disease, suggesting antibody immune responses occur early in the natural history of cancer progression.

CONCLUSIONS

These findings suggest an association between inflammatory conditions of the prostate and prostate cancer, and suggest that IgG responses to a panel of commonly recognized prostate antigens could be potentially used in the identification of patients at risk for prostate cancer or as a tool to identify immune responses elicited to prostate tissue. Prostate 71: 134–146, 2011. © 2010 Wiley‐Liss, Inc.
High‐fat diet increases NF‐κB signaling in the prostate of reporter mice
Authors: Vykhovanets Eugene V. , Shankar Eswar , Vykhovanets Olena V. , Shukla Sanjeev , Gupta Sanjay
Published: July 2010

BACKGROUND

High‐fat diet (HFD) is considered as a major risk factor for benign prostatic diseases and cancer in the Western world. Studies have shown an association between oxidative stress and prostatic diseases. NF‐κB has been implicated in stress response and is deregulated in prostrate disorders; therefore, we sought to determine whether HFD could induce oxidative stress in the prostate which could contribute to prostatic diseases.

METHODS

Transgenic NF‐κB‐Luc‐Tag mice were either fed with regular diet (RD) or HFD for 12 weeks. Serial, non‐invasive molecular imaging was performed to study NF‐κB activation in the whole body, and in various organs including thymus, spleen, and prostate. Western blotting was used to determine the expression of NF‐κB, its upstream and downstream targets in the prostate.

RESULTS

Twofold increase in whole body NF‐κB activity in vivo and two to threefold upregulated prostate NF‐κB activity ex vivo were observed after HFD intake compared with RD controls. HFD‐induced NF‐κB activity was elevated remarkably in the abdominal cavity, thymus, spleen, and prostate with increase in prostrate weight. In the prostrate, an increase in the protein expression of gp91phox, p22phox, and p47phox NADPH oxidase subunits was observed suggesting the involvement of HFD in causing oxidative stress. Nuclear extracts from the prostrate tissue showed an increased expression of p65/RelA that corresponded with elevated cytosolic levels of p‐IκBα, along with increased expression of downstream targets of NF‐κB, nitric oxide synthase, and cyclooxygenase‐2.

CONCLUSIONS

Our findings suggest that HFD‐mediated oxidative stress and deregulation of NADPH oxidase leads to NF‐κB activation in the prostrate. Prostate 71: 147–156, 2011. © 2010 Wiley‐Liss, Inc.
Structural refinement of the hERG1 pore and voltage‐sensing domains with ROSETTA‐membrane and molecular dynamics simulations
Authors: Subbotina Julia , Yarov‐Yarovoy Vladimir , Lees‐Miller James , Durdagi Serdar , Guo Jiqing , Duff Henry J. , Noskov Sergei Yu.
Published: July 2010

ThehERG1gene (Kv11.1) encodes a voltage‐gated potassium channel. Mutations in this gene lead to one form of the Long QT Syndrome (LQTS) in humans. Promiscuous binding of drugs to hERG1 is known to alter the structure/function of the channel leading to an acquired form of the LQTS. Expectably, creation and validation of reliable 3D model of the channel have been a key target in molecular cardiology and pharmacology for the last decade. Although many models were built, they all were limited to pore domain. In this work, a full model of the hERG1 channel is developed which includes all transmembrane segments. We tested a template‐drivende‐novodesign with ROSETTA‐membrane modeling using side‐chain placements optimized by subsequent molecular dynamics (MD) simulations. Although backbone templates for the homology modeled parts of the pore and voltage sensors were based on the available structures of KvAP, Kv1.2 and Kv1.2‐Kv2.1 chimera channels, the missing parts are modeledde‐novo. The impact of several alignments on the structure of the S4 helix in the voltage‐sensing domain was also tested. Herein, final models are evaluated for consistency to the reported structural elements discovered mainly on the basis of mutagenesis and electrophysiology. These structural elements include salt bridges and close contacts in the voltage‐sensor domain; and the topology of the extracellular S5‐pore linker compared with that established by toxin foot‐printing and nuclear magnetic resonance studies. Implications of the refined hERG1 model to binding of blockers and channels activators (potent new ligands for channel activations) are discussed. Proteins 2010. © 2010 Wiley‐Liss, Inc.
Docking and scoring protein interactions: CAPRI 2009
Authors: Lensink Marc F. , Wodak Shoshana J.
Published: July 2010

Protein docking algorithms are assessed by evaluating blind predictions performed during 2007–2009 in Rounds 13–19 of the community‐wide experiment on critical assessment of predicted interactions (CAPRI). We evaluated the ability of these algorithms to sample docking poses and to single out specific association modes in 14 targets, representing 11 distinct protein complexes. These complexes play important biological roles in RNA maturation, G‐protein signal processing, and enzyme inhibition and function. One target involved protein–RNA interactions not previously considered in CAPRI, several others were hetero‐oligomers, or featured multiple interfaces between the same protein pair. For most targets, predictions started from the experimentally determined structures of the free (unbound) components, or from models built from known structures of related or similar proteins. To succeed they therefore needed to account for conformational changes and model inaccuracies. In total, 64 groups and 12 web‐servers submitted docking predictions of which 4420 were evaluated. Overall our assessment reveals that 67% of the groups, more than ever before, produced acceptable models or better for at least one target, with many groups submitting multiple high‐ and medium‐accuracy models for two to six targets. Forty‐one groups including four web‐servers participated in the scoring experiment with 1296 evaluated models. Scoring predictions also show signs of progress evidenced from the large proportion of correct models submitted. But singling out the best models remains a challenge, which also adversely affects the ability to correctly rank docking models. With the increased interest in translating abstract protein interaction networks into realistic models of protein assemblies, the growing CAPRI community is actively developing more efficient and reliable docking and scoring methods for everyone to use. Proteins 2010. © 2010 Wiley‐Liss, Inc.
Side‐chain rotamer transitions at protein‐protein interfaces
Authors: Guharoy Mainak , Janin Joël , Robert Charles H.
Published: July 2010

We compare the changes in side chain conformations that accompany the formation of protein–protein complexes, in residues forming either the interface or the remainder of the solvent‐accessible surface of the proteins in the Docking Benchmark 3.0. We find that the interface residues undergo significantly more changes than other surface residues, and these changes are more likely to convert them from a high‐energy torsion angle state to a lower‐energy one than the reverse. Moreover, in both the unbound proteins and the complexes, the interface residues are more frequently found to be in a high‐energy torsion angle state than the noninterface residues. As these differences exist before the binding step, they may be relevant to specificity and help in identifying binding sites for docking predictions. Proteins 2010. © 2010 Wiley‐Liss, Inc.
Determination of an unusual secondary structural element in the immunostimulating tetrapeptide rigin in aqueous environments: insights via MD simulations, 1H NMR and CD spectroscopic studies
Authors: Kumar Nigam , Kishore Raghuvansh
Published: July 2010

An immunomodulating tetrapeptide, rigin (H‐Gly‐Gln‐Pro‐Arg‐OH), has been examined for its secondary structure preferences through combined use of high‐temperature unrestrained MD simulations in implicit water and 1D and 2D 1H NMR spectroscopy. The distribution of backbone torsion angles revealed the predominance of trans conformers across the Xaa‐Pro peptide bond. The results of MD simulations revealed that of the five predicted families A–E, the predominant families, family A (92 structures), family C (63 structures) and family D (31 structures), could be complemented by extensive 1D and 2D 1H NMR parameters acquired in aqueous PBS solution. A survey of specific inter‐ and intraresidue NOEs substantiated the predominance of an unusual type VII β‐turn structure, defined by two torsion angles, i.e. ψGln ∼ 155° and ϕPro ∼ − 65° across the Gln‐Pro segment. The proposed semi‐folded kinked topology precluded formation of any intramolecular interaction, i.e. hydrogen bond or electrostatic interaction. Far‐UV CD spectral characteristics of rigin in aqueous PBS solution and non‐aqueous structure‐promoting organic solvents, TFE and TMP, revealed its strong solvent dependence. However, in aqueous PBS solution, the presence of a weak negative shoulder at ${\sim234}$ nm could be ascribed to a small population with ordered, semi‐folded topology. We propose that the plausible structural attributes may be exploited for design and rigidification of the bioactive conformation of this immunomodulator toward improved immunopharmacological properties. Copyright © 2010 European Peptide Society and John Wiley & Sons, Ltd.
Azatryptophans as tools to study polarity requirements for folding of green fluorescent protein
Authors: Hoesl Michael Georg , Larregola Maud , Cui Haissi , Budisa Nediljko
Published: July 2010

Aequorea victoria green fluorescent protein and its widely used mutants enhanced green fluorescent protein and enhanced cyan fluorescent protein (ECFP) are ideal target proteins to study protein folding. The spectral signals of their chromophores are directly correlated with the folding status of the surrounding protein matrix. Previous studies revealed that tryptophan at position 57 (Trp57) plays a crucial role for the green fluorescent protein's structural and functional integrity. To precisely dissect its role in ECFP folding, we performed its substitution with the isosteric analogs 4‐azatryptophan [(4‐Aza)Trp] and 7‐azatryptophan [(7‐Aza)Trp]. Although Trp is moderately hydrophobic, these isosteric analogs are hydrophilic, which makes them an almost ideal tool to study the role of Trp57 in ECFP folding. We achieved high‐level expression of both (4‐Aza)Trp‐ECFP and (7‐Aza)Trp‐ECFP. However, great portions (70–90%) of protein samples were insoluble and did not contain a maturated chromophore. All attempts to refold the insoluble protein fractions failed. Nevertheless, low amounts of fully labeled, soluble, chromophore containing fractions with altered spectral features were also isolated and identified. The most probable reason for the high yield of misfolding is the introduction of strong hydrophilicity at position 57 which strongly interferes with productive and efficient folding of ECFP. In addition, the results support a strong correlation between translational kinetics of non‐canonical amino acids in the ribosome and in vivo folding of the related modified protein sequence. Copyright © 2010 European Peptide Society and John Wiley & Sons, Ltd.
Red ginseng extract improves coronary flow reserve and increases absolute numbers of various circulating angiogenic cells in patients with first ST‐segment elevation acute myocardial infarction
Authors: Ahn Chul Min , Hong Soon Jun , Choi Seung Cheol , Park Jae Hyung , Kim Jae Sang , Lim Do‐Sun
Published: July 2010

The effects of red ginseng extract on circulating angiogenic cell mobilization and improvement of microvascular integrity were evaluated in ST‐elevation acute myocardial infarction (AMI) patients during 8‐month follow‐up. AMI patients (n = 50) were randomly assigned to the red ginseng group (3 g/day, n = 25) or the placebo group (n = 25) after coronary stenting. Coronary flow reserve (CFR) was measured at baseline and at 8 months with an intracoronary Doppler wire. Serial changes in the absolute numbers of circulating angiogenic cells such as CD34+, CXCR4+, CD117+, CD133+ and C‐met+ were measured at baseline, 1 day, 5 days and at 8 months.

CFR were similar between the two groups at baseline, and CFR was significantly higher in the red ginseng group than in the placebo group (2.80 ± 0.91 and 2.56 ± 0.77, p < 0.05, respectively) after 8 months of red ginseng administration. The absolute numbers of circulating CD34+, CXCR4+ and CD117+ cells were significantly higher in the red ginseng group at 1 and 5 days after stenting. Significant positive correlations were found between the numbers of circulating angiogenic cells at day 1 and the changes from baseline in CFR for CD34+, CXCR4+, CD117+ and C‐met+ cells. Red ginseng extract increased CD34+, CXCR4+ and CD117+ circulating angiogenic cell mobilization and decreased inflammation in AMI patients, thereby improving CFR during the 8‐month follow‐up. Copyright © 2010 John Wiley & Sons, Ltd.