bluuebunny/crossref_metadata_2025 huggingface dataset:
Photo‐Crosslinkable Poly(trimethylene carbonate)‐Based Macromers for Closure of Ruptured Intervertebral Discs
Authors: Sharifi Shahriar , Kranenburg Hendrik‐Jan C. , Meij Björn P. , Grijpma Dirk W.
Published: December 2011

In patients with low back pain, surgical removal of the partially herniated nucleus pulposus may lead to clinical improvement but ultimately leads to intervertebral disc degeneration and recurrence of back pain is frequent. As an alternative treatment, use of an injectable material which solidifies in situ, is proposed. Such materials can easily fill oddly‐shaped defects in the annulus fibrosus and seal the disc through a minimally invasive surgical procedure, thereby protecting the disc from further degeneration. In this study, a series of injectable and photo‐crosslinkable macromers based on poly trimethylene carbonate (PTMC) and polyethylene glycol (PEG) were prepared. It is shown that these materials are injectable and solidify within two minutes upon illumination with visible light. By varying the PTMC to PEG block ratios, material properties such as elastic modulus and water content could easily be tuned to match those of the native annulus fibrosus. Ex vivo results using canine cadaveric spines showed the potential of the materials to seal an opening in the annulus fibrosus, although the adhesion of the photo‐crosslinked material to the disc tissue needs to be improved.
Reducing the Endotoxin Burden of Desaminotyrosine‐ and Desaminotyrosyl Tyrosine‐Functionalized Gelatin
Authors: Roch Toralf , Pierce Benjamin F. , Zaupa Alessandro , Jung Friedrich , Neffe Axel T. , Lendlein Andreas
Published: December 2011

Biomaterial‐induced autoregeneration requires materials with distinct tailored mechanical and thermal properties, water uptake and swelling properties as well as degradation behavior. Furthermore, before any biomaterial can be applied in vivo, in vitro studies should be performed that confirm the suitability for such applications. One facet in this process is the evaluation of endotoxin loads and immunogenic response to the material to avoid an unspecific activation of the immune system, which otherwise might cause fever and could lead to life–threatening pathologies. In this study, gelatins functionalized with desaminotyrosine (DAT) or desaminotyrosyl tyrosine (DATT) were investigated in terms of their endotoxin content and their potential to induce an inflammatory cytokine response in macrophages. Using the Limulus amebocyte lysate (LAL) test it could be shown that the endotoxin content was substantially reduced by using certified low endotoxin containing gelatin and performing the gelatin functionalization under cleanroom conditions. Furthermore, production of inflammatory cytokines such as interleukin 6 (IL‐6) and tumor necrosis factor–alpha (TNFα) of an immune relevant macrophage cell line was significantly reduced for these materials. The survival of the macrophage cell line in the presence of DAT(T)‐functionalized gelatins was not influenced by both materials. Therefore, DAT‐ and DATT‐functionalized gelatins were shown to have passed the tests concerning immunological responses important for their applicability in vivo.
In Vivo Application of Poly(1,3‐trimethylene carbonate) as a Scleral Buckle in a Rabbit Model
Authors: Wójcik Katarzyna , Verdoold Vincent , Koopmans Steven A. , de Vos Sandra N.V. , Grijpma Dirk W.
Published: December 2011

Retinal detachments can be repaired with the use of cerclages. Currently non‐resorbable silicone scleral buckle implants are used to indent the eye and in that way increase the internal pressure of the eye. The use of resorbable implants has advantages over using non‐resorbable materials. High molecular weight poly(1,3‐trimethylene carbonate) (PTMC) is a flexible and biodegradable polymer that has great potential in soft tissue engineering and the preparation of resorbable implants like scleral buckles. To be able to use PTMC devices in clinical applications, a full biocompatibility study of the polymer was first evaluated. Then the indentation of the eye over time using a PTMC scleral buckle was assessedin vivoin a rabbit model.
Synthesis and Characterization of a Telechelic Peptide as a Precursor for Supramolecular Networks
Authors: Federico Stefania , Lendlein Andreas , Neffe Axel T.
Published: December 2011

A peptide showing propensity for the adoption of β‐sheet conformation was synthesized in order to develop a defined molecular building block as part of a toolbox for the development of polymer networks based on supramolecular interactions. The peptide was synthesized by microwave‐assisted solid phase peptide synthesis and the purification was performed by Reversed Phase‐High Performance Liquid Chromatography (RP‐HPLC), from which a purity higher than 95 mol‐% was obtained. The calculated mass was confirmed by Matrix Assisted Laser Desorption Ionization‐Time of Flight‐Mass Spectrometry (MALDI‐ToF‐MS). Further characterization of the peptide was performed by IR and 2D TOCSY, NOESY, and HSQC NMR spectroscopy, which confirmed the identity and the sequence of the peptide.
Age, CAG repeat length, and clinical progression in Huntington's disease
Authors: Rosenblatt Adam , Kumar Brahma V. , Mo Alisa , Welsh Claire S. , Margolis Russell L. , Ross Christopher A.
Published: December 2011

The objective of this study was to further explore the effect of CAG repeat length on the rate of clinical progression in patients with Huntington's disease. The dataset included records for 569 subjects followed prospectively at the Baltimore Huntington's Disease Center. Participants were seen for a mean of 7.1 visits, with a mean follow‐up of 8.2 years. Subjects were evaluated using the Quantified Neurologic Examination and its Motor Impairment subscale, the Mini‐Mental State Examination, and the Huntington's disease Activities of Daily Living Scale. By itself, CAG repeat length showed a statistically significant but small effect on the progression of all clinical measures. Contrary to our previous expectations, controlling for age of onset increased the correlation between CAG repeat length and progression of all variables by 69% to 159%. Graphical models further supported the idea that individuals with smaller triplet expansions experience a more gradual decline. CAG repeat length becomes an important determinant of clinical prognosis when accounting for age of onset. This suggests that the aging process itself influences clinical outcomes in Huntington's disease. Inconsistent results in prior studies examining CAG repeat length and progression may indeed reflect a lack of age adjustment. © 2011 Movement Disorder Society
Ultrawideband quadrature power divider employing double wireless via
Authors: Ibrahim Siti Zuraidah , Bialkowski Marek E. , Abbosh Amin M.
Published: December 2011

The article reports the design of an ultrawideband quadrature power divider in uniplanar microstrip technology. The proposed device uses the conventional Wilkinson power divider with one of its output arms equipped with a double wireless via acting as a phase adjusting circuit. The device is manufactured showing a wide bandwidth in terms of return loss, isolation, power division, and a differential phase shift of 90° across the frequency band of 3–8 GHz. Its compact size and good performance makes it suitable for use in wideband‐balanced amplifiers. © 2011 Wiley Periodicals, Inc. Microwave Opt Technol Lett, 54:300–305 2012; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.26519
A miniaturized dual band bow‐tie microstrip antenna for implantable and wearable telemedicine applications
Authors: Rucker Daniel G. , Al‐Rizzo Hussain M. , Wolverton Michael J. , Khaleel Haider R.
Published: December 2011

In this article, a miniaturized dual band, multislotted bow‐tie microstrip antenna for wearable telemedicine applications involving a bidirectional wireless link between implantable and wearable systems is proposed. The number, size, and position of the slots, center width, as well as the size of the ground plane, were selected to control the TM30 mode such that the antenna resonates at the desired frequencies and provides the radiation patterns for the intended application. The antenna operates with a dipole‐like radiation pattern in the 915 MHz band and a broadside radiation pattern in the 2.45 GHz band. The reflection coefficient and far‐field radiation patterns were measured and compared against the simulated results. © 2011 Wiley Periodicals, Inc. Microwave Opt Technol Lett, 54:365–369, 2012; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.26523
A 60‐GHz three‐stage low noise amplifier using 0.15‐μm gallium‐arsenic pseudomorphic high‐electron mobility transistor technology
Authors: Hu Chih‐Min , Hung Chung‐Yu , Chu Chun‐Hsueh , Chang Da‐Chiang , Juang Ying‐Zong , Gong Jeng , Huang Chih‐Fang , Chin Chih‐Min
Published: December 2011

A 60 GHz monolithic low‐noise amplifier (LNA) fabricated with 0.15‐μm gallium‐arsenic pseudomorphic high‐electron mobility transistors is presented.Using a three‐stage cascaded topology and in‐stage transmission lines, the LNA is designed using 5 V power supply voltage. Measured results of the LNA show the peak gain of 13.5 dB and the lowest noise figure of 5.15 dB around 61 GHz, and the 1 dB compression point (P1dB) of the LNA is −10 dBm. The LNA also demonstrates a complete design flow for millimeter‐wave applications. © 2011 Wiley Periodicals, Inc. Microwave Opt Technol Lett, 54:329–332, 2012; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.26525
Envelope tracking power amplifier with saturated driver amplifier optimized for overall efficiency
Authors: Jeong Jinseong
Published: December 2011

This letter presents a new technique to enhance the overall efficiency of a two‐stage envelope tracking (ET) power amplifier (PA). Because of heavy gain compression, ET amplifiers can suffer from inefficient driver stages. By reducing the supply voltage of the driver amplifier, its efficiency can be improved without degrading the linearity performance of the overall PA system because the final‐stage ET PA allows the decrested RF signal as an input. This technique is demonstrated for a single carrier WCDMA signal using a RF PA based on a GaAs HVHBT with a dynamic supply modulator and a driver stage based on a GaN heterojunction field‐effect transistor (HFET). The measurement shows that the drain efficiency of the driver amplifier is improved from 25.6 to 41.5% and the overall efficiency of the ET PA system is improved from 46.2 to 48.3% while the efficiency of the final‐stage ET PA is maintained at higher than 55%. The average output power is greater than 44.6 dBm, the overall gain is greater than 20 dB, and the adjacent channel leakage ratio is less than −46 and −53 dBc at 5‐ and 10‐MHz frequency offsets, respectively. © 2011 Wiley Periodicals, Inc. Microwave Opt Technol Lett, 54:505–507, 2012; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.26527
ANFIS models for synthesis of micro‐coplanar stripline and asymmetric coplanar stripline with an infinitely wide strip
Authors: Kaya S. , Guney K. , Yildiz C. , Turkmen M.
Published: December 2011

In this letter, computer‐aided design models based on adaptive‐network‐based fuzzy inference system (ANFIS) for the synthesis of two coplanar stripline structures are presented.These coplanar stripline structures are micro‐coplanar stripline and asymmetric coplanar stripline with an infinitely wide strip. Four optimization algorithms, hybrid learning (HL), simulated annealing, least‐squares, and genetic, are used to determine optimally the design parameters of the ANFIS models. The results of ANFIS models are compared with the results of quasi‐static analysis, synthesis formulas available in the literature, a full‐wave electromagnetic simulator IE3D, and experimental works realized in this study. The results of ANFIS models agree with the results of other methods and experimental works. When the performances of ANFIS models are compared with each other, the best results for training and test are obtained from the models trained with HL algorithm. © 2011 Wiley Periodicals, Inc. Microwave Opt Technol Lett, 54:460–467, 2012; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.26530
Design of a K‐band reflectarray antenna using double square ring elements
Authors: Ma Bing , Xia Mingyao , Yan Lubin
Published: December 2011

Design of a K‐band reflectarray antenna using 15 × 15 double square ring elements printed on a single substrate and backed by a ground plane separated by an air layer is proposed. The double square ring element supplies a 530° dynamic range of the reflection phase variation, and the phasing curves are nearly linear. A prototype is manufactured and tested, and good agreements between simulation and measurement are demonstrated. The measured gain is about 23 dBi at the center frequency 24 GHz, and the 1‐dB gain bandwidth is about 20%. © 2011 Wiley Periodicals, Inc. Microwave Opt Technol Lett, 54:394–398, 2012; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.26535
An ultrawideband bandpass filter with steeply sloped rejection using stub‐loaded resonator
Authors: Xu Jin , Hua Changzhou , Li Bo , Wang Hui , Miao Chen , Wu Wen
Published: December 2011

An ultrawideband (UWB) bandpass filter with steeply sloped rejection is proposed in this article. The proposed filter has five transmission poles inside the passband and four transmission zeros on both side of passband. Using the even‐ and odd‐mode analysis method, closed‐form formulas for the position of poles and zeros are given. Finally, a UWB bandpass filter is fabricated and measured. The simulation and measurement agree well with each other. Furthermore, due to the two tunable transmission zeros very close to the filter passband, the fabricated filter has 136‐ and 72‐dB/GHz slopes in the lower and upper transition band. © 2011 Wiley Periodicals, Inc. Microwave Opt Technol Lett, 54:326–329, 2012; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.26538
Experiments on through‐wall imaging using ultra wideband radar
Authors: Dionisio Carlos R. P. , Tavares Sérgio , Perotoni Marcelo , Kofuji Sergio
Published: December 2011

Through‐wall imaging (TWI) may provide vital information on interior environment in cases when physically entering such environment would pose danger to the person involved.The concept of ultra wideband radar (UWB radar) is an emerging technology, which offers high spatial resolution, as opposed to narrow band radars. Thus, TWI applications using UWB radar have become a growing field of research with several applications in the civil and defense areas such as rescue and surveillance. For this study, a prototype system of UWB radar to TWI has been built. Analyses and result to several kinds of experiments have been presented, that is, detection and visualization of metallic targets behind wooden board wall and concrete blocks wall. The results are encouraging and show the advantages of using UWB radar for TWI. © 2011 Wiley Periodicals, Inc. Microwave Opt Technol Lett, 54:339–344, 2012; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.26543
A planar monopole UWB antennas with rounded patch and ground plane possessing improved impedance matching
Authors: Melo D. R. , Kawakatsu M. N. , Nascimento D. C. , Dmitriev Victor
Published: December 2011

A planar monopole UWB antenna with rounded patch and rounded truncated ground plane for ultra‐wideband applications is investigated. The geometry of the antenna is optimized to obtain a minimum return loss. The antenna provides the return loss better than −15 dB in almost the entire (3.1–10.6) GHz frequency band and good radiation characteristics. The simulated and experimental results are in a good agreement. © 2011 Wiley Periodicals, Inc. Microwave Opt Technol Lett, 54:335–338, 2012; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.26544
Resonant filtering characteristic of symmetrical complementary metamaterial at terahertz frequencies
Authors: Zhang Bao‐Yue , Li Jiu‐Sheng
Published: December 2011

An equivalent circuit model was used to analyze a symmetrical complementary metamaterial for resonant filtering characteristic at terahertz frequencies. Using terahertz time‐domain spectroscopy system, we examined the transmittance spectra for the metamaterial structure. The experimental results validate those of the theoretical predictions. The structure could lead to be a terahertz wave bandpass filter with a narrow transmission bandwidth centered at 2.01 THz and very sharp edges. © 2011 Wiley Periodicals, Inc. Microwave Opt Technol Lett, 54:351–354, 2012; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.26548
A new approach to the design of a dual‐band IFA with a metamaterial unit cell
Authors: Kim Sangwon , Choi Hak Keun , Choi Jae Ick , Park Jae Hyun
Published: December 2011

This article proposes a new approach to obtaining a dual‐band inverted‐F antenna (IFA) with a novel metamaterial unit cell providing a negative index of refraction. The dual‐resonance characteristic of the proposed IFA can be achieved because of the stop‐band property of the metamaterial unit cell. The novel metamaterial unit cell of the proposed antenna has a positive refractive index (PRI), a negative refractive index (NRI), and the stop‐band property between PRI and NRI. In addition, to control the resonant frequency of the proposed antenna, a capacitor is loaded in the metamaterial unit cell. To prove the validity of the proposed antenna, the properties of a homogeneous frequency‐dependent (HFD) material, which can be represented in the HFSS software, are used. The metamaterial is replaced by the HFD material to confirm the effective constitutive parameters of the metamaterial unit cell. It is confirmed that the results using the metamaterial and the HFD material are similar. To prove the validity of the proposed design approach, a good agreement between experimental results and theoretical predictions is demonstrated, meaning that the approach is usable for practical applications. © 2011 Wiley Periodicals, Inc. Microwave Opt Technol Lett, 54:545–549, 2012; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.26554
Photonic generation and radio transmission of ECMA 387 signal at 60 GHz using WDM demultiplexer
Authors: Shao Tong , Paresys Flora , Guennec Yannis Le , Maury Ghislaine , Corrao Nicolas , Cabon Beatrice
Published: December 2011

We propose to realize an experimental setup for millimeter wave (mmW) band Radio over Fiber system using wavelength division multiplexing technique.In this article, broadband mmW at 60‐GHz band, which is compliant with the ECMA 387 standard, is generated by photodetection and transmitted with horn antennas. © 2011 Wiley Periodicals, Inc. Microwave Opt Technol Lett, 54:275–277, 2012; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.26556
Experimental and numerical study of highly sensitive displacement sensors based on photonic crystals at microwave band
Authors: Sha Shaoshu , Zhai Huiqing , Rowda Vinay R. , Chen Nan‐Wei , Zhou Weidong , Lu Mingyu
Published: December 2011

Structures composed of two photonic crystal slabs are fabricated, measured, and simulated around 13.5 GHz.Experimental and simulated results are in good agreement. The transmission spectrum is highly sensitive to the distance between the two slabs, which demonstrates that the structures under investigation can be used to achieve displacement sensors. © 2011 Wiley Periodicals, Inc. Microwave Opt Technol Lett 54:432–434, 2012; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.26558
Planar microstrip monopole antenna for UPCS and UWB applications
Authors: Morsy Mohamed M. , Khan Muhammad R. , Harackiewicz Frances J.
Published: December 2011

This letter presents a microstrip‐fed antenna that is compact, low profile, and planar.The antenna is suitable for UPCS (1.85–1.99 GHz) and UWB applications. The antenna occupies an area of 20 × 40 mm2. The antenna exhibits dual frequency bands at 1.8–2 GHz and 3.825–8.177 GHz with good radiation pattern characteristics. The antenna radiation pattern is almost as the radiation pattern of a monopole antenna, and the gain remains nearly constant within UPCS and UWB bands. The antenna is suitable for application to wireless communication systems. Finally, there is good agreement between the measured and the simulated results. © 2011 Wiley Periodicals, Inc. Microwave Opt Technol Lett 54:496–500, 2012; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.26564
Multiresonance printed monopole antenna for DCS/WLAN/WIMAX applications
Authors: Lavakhamseh H. , Ghobadi Ch. , Nourinia J. , Ojaroudi M.
Published: December 2011

In this article, a novel printed monopole antenna is presented for simultaneously satisfying DCS, wireless local area network (WLAN), and worldwide interoperability for microwave access (WiMAX) applications.The operating frequencies of the proposed antenna are 1.8 GHz, which covers DCS operations, 2.4/5.2/5.8 GHz for WLAN system and 2.5/3.5/5.5 GHz for WiMAX system. The desired resonant frequencies are obtained by adjusting the length of folded Γ‐shaped arms. Also by cutting an H‐shaped slot in the bottom of microstrip feedline on the ground plane, much wider impedance bandwidth can be produced. Prototypes of the proposed antenna have been constructed and studied experimentally. The measured results show good agreement with the numerical prediction and good multiband operation. © 2011 Wiley Periodicals, Inc. Microwave Opt Technol Lett 54:297–300, 2012; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.26572
Investigation of internal nonhomogenous volumes of perturbation as tuning and miniaturization elements for cavity resonators
Authors: Dancila D. , Rottenberg X. , Tilmans H. A. C. , De Raedt W. , Huynen I.
Published: December 2011

In this article, we investigate the tuning and miniaturization performance induced by a volume perturbation inserted in a cavity resonator. The volume perturbation is either a rectangular perturbation centrally located, called central postperturbation (CPP) or dually, a hole shaped in an annular extruded volume, called side annular perturbation (SAP). The tuning and miniaturization mechanism is fully described using the small perturbation theory. This serves the analytical evaluation of the frequency shift resulting from the insertion of the perturbation volume in the cavity resonator. The impact of these perturbations is assessed also by HFSS simulations and measurements of 72 different cavity resonators. An idle cavity resonator characterized by a resonance frequency of 4 GHz is tuned from 1 to 6 GHz. A maximal frequency shift of 3 GHz and 2 GHz is measured for respectively the resonator with CPP and SAP, resulting in a total tuning range of 125%. Additionally, the CPP serves miniaturization purposes, as cavity resonators with a resonance frequency as low as 1 GHz were measured, derived from an idle cavity resonator at 4 GHz. © 2011 Wiley Periodicals, Inc. Microwave Opt Technol Lett 54:491–496, 2012; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.26578
A triple band‐notched planar monopole antenna for ultrawide band applications
Authors: Natarajamani S. , Behera Santanu Kumar , Patra Sarat Kumar
Published: December 2011

This article presents the compact planar antenna with 3.5/5.5/8.2 GHz triple band‐notched characteristics. The antenna consists of an octagon shape patch with 50 Ω transmission line. By etching two C‐shaped slots in the patch and adding pair of L‐shaped resonator coupled to the radiating patch, band‐rejected filtering properties in the WiMAX/WLAN/ITU bands are achieved. The proposed ultrawide band (UWB) antenna is optimized to operate in the frequency band from 3 to 11 GHz for VSWR < 2. Measured results confirm that the antenna is suitable for UWB applications because of its compact size and high performance. © 2011 Wiley Periodicals, Inc. Microwave Opt Technol Lett 54:539–543, 2012; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.26581
Transmissive fiber optical displacement sensor using cutting plate
Authors: Hu Xiaogen , Li Yuhe , Chen Yanxiang
Published: December 2011

Intensity modulated transmissive fiber optical displacement sensor is introduced and its performance is investigated.In the experiments, the relative error is 4% and the linearity is higher than 99.2% with source light intensity stable. The relative error is 0.2% with the source light intensity changed at a certainly frequency. © 2011 Wiley Periodicals, Inc. Microwave Opt Technol Lett 54:446–448, 2012; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.26586
37–38 GHz substrate integrated filtenna for wireless communication application
Authors: Yu Chen , Hong Wei
Published: December 2011

The seamless or incorporate design of RF filter and antenna is very important for size and loss reduction in the design of millimeter wave wireless communication systems.Such antenna is then called as filtenna. In this article, an integrated design of the filter and antenna or filtenna at 37–38 GHz for local‐multipoint‐distribution‐system (LMDS) based on substrate integrated waveguide (SIW) technology is presented. One slot and two‐slot SIW antennas and corresponding filtennas are simulated, fabricated and measured. By comparing the measured return loss and radiation patterns between the filtenna and the original antenna, it is concluded that the performance of the filtenna is kept nearly no change within the working frequency band while the out of band signal is effectively filtered. © 2011 Wiley Periodicals, Inc. Microwave Opt Technol Lett 54:346–351, 2012; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.26589
Single‐/multiband CMOS low‐noise amplifier using concentric switching inductors
Authors: Wang Ruey‐Lue , Chen Shih‐Chih , Huang Cheng‐Lin
Published: December 2011

In this article, a low‐noise amplifier (LNA) using concentric switching inductors were designed and measured. A voltage supply is fed through the switching inductors. The presented circuit is a modified cascoded amplifier configuration which input stage is a common‐gate structure. The switching inductors are implemented by three series‐wound concentric planar spiral inductors associated with two PMOSFET switches. According to on or off state of two PMOSFET switches, the circuit has theoretically four transfer characteristics, including one single‐band, two dual‐band, and one triple‐band frequency responses. For the LNA, using the concentric‐type switching inductors, the simulated and measured gains are nearly more than 12 and 10 dB at all operation frequency bands, respectively. The measured reflection coefficients are almost less than −10 dB at all operation frequency bands. The measured minimum noise figures are almost less than 4.5 dB at all operation frequency bands. The power consumption is 9 mW. The chip size is 1.03 × 1.04 mm2. © 2011 Wiley Periodicals, Inc. Microwave Opt Technol Lett 54:309–315, 2012; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.26591
Performance analysis of pure paraffin wax as RFID tag substrate
Authors: Manzari S. , Babar A. A. , Ukkonen L. , Elsherbeni Atef Z. , Marrocco G. , Sydänheimo L.
Published: December 2011

The article presents an investigation of the performance of the Paraplast, a kind of pure paraffin wax, used as a substrate of RFID tag antennas operating at UHF RFID band. To achieve this purpose, two similar RFID tag antennas with same dimensions have been simulated, fabricated and tested. These include a simple dipole tag on a Rogers RT/Duroid 5880 substrate and on pure paraffin substrate. Because of the relatively close dielectric constant values, paraffin substrate is compared with Duroid RT5880. Paraffin wax can be considered as a low cost and low loss substrate. The main purpose in the future will be using paraffin as a passive temperature sensor, by exploiting the changes in molecular structure, volume and dielectric properties with temperature, especially near its melting point. © 2011 Wiley Periodicals, Inc. Microwave Opt Technol Lett 54:442–446, 2012; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.26592
Non‐viral transfection of goat germline stem cells by nucleofection results in production of transgenic sperm after germ cell transplantation
Authors: Zeng W. , Tang L. , Bondareva A. , Luo J. , Megee S.O. , Modelski M. , Blash S. , Melican D.T. , Destrempes M.M. , Overton S.A. , Gavin W.G. , Ayres S. , Echelard Y. , Dobrinski I.
Published: December 2011

Germline stem cells (GSCs) can be used for large animal transgenesis, in which GSCs that are genetically manipulated in vitro are transplanted into a recipient testis to generate donor‐derived transgenic sperm. The objectives of this study were to explore a non‐viral approach for transgene delivery into goat GSCs and to investigate the efficiency of nucleofection in producing transgenic sperm. Four recipient goats received fractionated irradiation at 8 weeks of age to deplete endogenous GSCs. Germ cell transplantations were performed 8–9 weeks post‐irradiation. Donor cells were collected from testes of 9‐week‐old goats, enriched for GSCs by Staput velocity sedimentation, and transfected by nucleofection with a transgene construct harboring the human growth hormone gene under the control of the goat beta‐casein promoter (GBC) and a chicken beta‐globin insulator (CBGI) sequence upstream of the promoter. For each recipient, transfected cells from 10 nucleofection reactions were pooled, mixed with non‐transfected cells to a total of 1.5 × 108 cells in 3 ml, and transplanted into one testis (n = 4 recipients) by ultrasound‐guided cannulation of the rete testis. The second testis of each recipient was removed. Semen was collected, starting at 9 months after transplantation, for a period of over a year (a total of 62 ejaculates from four recipients). Nested genomic PCR for hGH and CBGI sequences demonstrated that 31.3% ± 12.6% of ejaculates were positive for both hGH and CBGI. This study provides proof‐of‐concept that non‐viral transfection (nucleofection) of primary goat germ cells followed by germ cell transplantation results in transgene transmission to sperm in recipient goats. Mol. Reprod. Dev. 79: 255–261, 2012. © 2011 Wiley Periodicals, Inc.
Glycolysis in preimplantation development is partially controlled by the Warburg Effect
Authors: Redel Bethany K. , Brown Alana N. , Spate Lee D. , Whitworth Kristin M. , Green Jonathan A. , Prather Randall S.
Published: December 2011

Glucose metabolism in preimplantation embryos has traditionally been viewed from a somatic cell viewpoint. Here, we show that gene expression in early embryos is similar to rapidly dividing cancer cells. In vitro‐produced pig blastocysts were subjected to deep‐sequencing, and were found to express two gene variants that have been ascribed importance to cancer cell metabolism (HK2 and the M2 variant of PKM2). Development was monitored and gene expression was quantified in additional embryos cultured in low or high O2 (5% CO2, 5% O2, 90% N2 vs. 5% CO2 in air). Development to the blastocyst stage in the two atmospheres was similar, except low O2 resulted in more total and inner cell mass nuclei than high O2. Of the 15 candidate genes selected that are involved in glucose metabolism, only TALDO1 and PDK1 were increased in the low O2 environment. One paradigm that has been used to explain glycolysis under low oxygen tension is the Warburg Effect (WE). The WE predicts that expression of both HK2 and PKM2 M2 results in a slowing of glucose metabolism through the TCA cycle, thereby forcing the products of glycolysis to be metabolized through the pentose phosphate pathway and to lactic acid. This charging of the system is apparently so important to the early embryo that redundant mechanisms are present, that is, a fetal form of PKM2 and high levels of PDK1. Here, we set the framework for using the WE to describe glucose metabolism and energy production during preimplantation development. Mol. Reprod. Dev. 79: 262–271, 2012. © 2011 Wiley Periodicals, Inc.
An approximate dynamic programming method for multi‐input multi‐output nonlinear system
Authors: Huang Zhijian , Ma Jie , Huang He
Published: December 2011

Approximate dynamic programming is a useful tool in solving multi‐stage decision optimal control problems. In this work, we first promote the action‐dependent heuristic dynamic programming method to multi‐input multi‐output control system by extending its action network to multi‐output form. The detailed derivation is also given. We then apply this method to the fluctuation control of a spark engine idle speed. An engine idling model is set up to verify the control effect of this method. Results here show that this method requires several iterations to suppress unbalanced combustion by manipulating spark ignition timing. This method provides an alternative for a simpler multi‐input multi‐output approximate dynamic programming scheme. Moreover, it has a faster iteration convergence effect. The derivation of this method also has a rigorous mathematical basis. Although illustrated for engines, this control system framework should also be applicable to general multi‐input multi‐output nonlinear system. Copyright © 2011 John Wiley & Sons, Ltd.
Could MDMA be useful in the treatment of post‐traumatic stress disorder?
Authors: Sessa Ben
Published: December 2011

In recent studies, 3,4‐methylenedioxymethylamphetamine (MDMA) has shown promise in the treatment of post‐traumatic stress disorder (PTSD) as an adjunct to post‐trauma psychological therapy. However, because of historical associations with its use as the recreational drug ecstasy, MDMA research remains a controversial subject. Dr Sessa discusses these controversies and describes a UK‐based MDMA/PTSD currently in development. Copyright © 2011 John Wiley & Sons, Ltd.
Managing bipolar depression: a therapeutic challenge?
Authors: Feetam Celia
Published: December 2011

Most people with bipolar disorder first seek treatment for depressive rather than manic symptoms. However, effective management of bipolar depression remains a challenge. In this review, Celia Feetam highlights how bipolar depression differs from unipolar depression both in its characteristics and in the approach to its treatment. Copyright © 2011 John Wiley & Sons, Ltd.
Controlled radical polymerization of tert‐butyl acrylate at ambient temperature: Effect of initiator structure and synthesis of amphiphilic block copolymers
Authors: Sundaram Harihara Subramanian , Raghavachari Dhamodharan
Published: December 2011

Controlled and very rapid ambient temperature polymerization of tert‐butyl acrylate (tBA) via atom transfer radical polymerization (ATRP) and single electron transfer living radical polymerization (SET‐LRP) conditions is reported. Two initiators, one that would generate a secondary radical and another that would generate a primary radical, upon activation, are used. A very active catalyst CuBr/Me6TREN was found to initiate rapid polymerization whether it was the primary or the secondary initiator. The polymerization was well controlled and very rapid. The initiator that produces secondary initiating site is found to result in more rapid polymerization than the one that produces primary initiating site. To explore the possibility of rapid ambient temperature polymerization through the SET‐LRP mechanism, the polymerization was also carried out in the presence of DMSO. It was found that the polymerization was much faster compared to the bulk ATRP, without loss of control. Styrene was block copolymerized from PtBA macroinitiators and vice versa. In both the cases, block copolymers with controlled molecular weights were obtained. The tBA block of the polymer was selectively hydrolyzed to get amphiphilic block copolymers. This amphiphilic block copolymer was found to be useful in preparing stable cadmium sulfide (CdS) nanoparticulate dispersion. © 2011 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2012
Bereaved siblings' perception of participating in research—a nationwide study
Authors: Eilegård Alexandra , Steineck Gunnar , Nyberg Tommy , Kreicbergs Ulrika
Published: December 2011

Objective

The objective of the present study is to examine bereaved siblings' perception of research participation.

Methods

A Swedish nationwide study on avoidable and modifiable health care‐related factors in paediatric oncology among bereaved siblings who lost a brother or sister to cancer between the years 2000 and 2007 was conducted. Data are presented as proportions, and the differences between groups were statistically tested at the 5% significant level using Fisher's exact test.

Results

Out of 240 eligible siblings, 174 responded (73 %). None of the siblings (0/168) thought their participation would affect them negatively in the long term. However, 13% (21/168) stated it was a negative experience to fill out the questionnaire, whereas 84% (142/169) found it to be a positive experience. Women were more likely to report their participation as positive in a long‐term perspective compared with men (p = 0.018).

Conclusions

None of the bereaved siblings in this Swedish nationwide study anticipated any long‐term negative effect from their research participation. A majority reported it as positive to revisit their needs and experiences throughout their brother or sister's illness and death 2–9 years following the loss. We believe that the stepwise approach used in this study contributed to the high acceptance. Copyright © 2011 John Wiley & Sons, Ltd.
Quantification of impurity concentration in Cu2O and CuO via secondary ion mass spectrometry
Authors: Laufer Andreas , Reppin Daniel , Metelmann Hauke , Geburt Sebastian , Ronning Carsten , Leichtweiss Thomas , Janek Jürgen , Meyer Bruno K.
Published: December 2011

Secondary ion mass spectrometry (SIMS) is a technically matured analysis technique for the investigation of depth and lateral distributions in solids. The “raw data” of a SIMS measurement provides only qualitative information. For quantification so‐called relative sensitivity factors (RSF) are mandatory. To our knowledge no RSFs have been determined for Cu2O and CuO so far. In this work the RSFs for 21 elements in Cu2O and 14 elements in CuO have been determined via ion implanted standards. For the RSF determination we present the plateau method (Section 3) for box‐like implantation profiles. This method provides a lower uncertainty in RSF value compared to the obtained uncertainty using single implantation profiles. In addition, we have estimated the electron affinities of NO2, AsO2 and SbO to 0.55, 2.7 and 2.85 eV, respectively. Unexpectedly, we observe for Cu2O and CuO nearly identical RSF values. This behaviour cannot be attributed to a change in chemical composition caused by the SIMS sputter process. Furthermore, the calculated RSFs have been used to determine the impurity concentrations of our sputtered copper oxide thin films.
Hot Water Extract of Adzuki (Vigna angularis) Suppresses Antigen‐Stimulated Degranulation in Rat Basophilic Leukemia RBL‐2H3 Cells and Passive Cutaneous Anaphylaxis Reaction in Mice
Authors: Itoh Tomohiro , Hori Yumiko , Atsumi Toshiyuki , Toriizuka Kazuo , Nakamura Masahiro , Maeyama Takeshi , Ando Masashi , Tsukamasa Yasuyuki , Ida Yoshiteru , Furuichi Yukio
Published: December 2011

The hot water extract of adzuki (HWEA), which is produced as a byproduct in the adzuki bean boiling process, has anti‐tumor, antioxidative, and anti‐diabetic activities. In this study, we fractionated HWEA to 4 fractions using stepwise gradient column chromatography with water and ethanol, and demonstrated the effects of each fraction on antigen (Ag)‐stimulated degranulation in rat basophilic leukemia RBL‐2H3 cells. The 40% ethanol eluate extract (EtEx.40) showed the strongest inhibition level of these fractions. To reveal the inhibitory mechanisms underlying degranulation by EtEx.40, we investigated intracellular reactive oxygen species (ROS) production, intracellular free Ca2+ concentration ([Ca2+]i), and early intracellular signaling pathways. Treatment with EtEx.40 markedly inactivated Lyn following Ag stimulation, resulting in the suppressions of intracellular elevation of [Ca2+]i and production of ROS. To identify the active compound in EtEx.40, we isolated 7 flavonoids from EtEx.40 and calculated their inhibition levels on Ag‐stimulated degranulation. These flavonoids inhibited degranulation by about 25–60%. We further examined the in vivo effects of HWEA or EtEx.40 using a passive cutaneous anaphylaxis (PCA) reaction. Both extracts strongly suppressed the PCA reaction. These findings suggest that HWEA and/or EtEx.40 are beneficial for alleviating type I allergic symptoms. Copyright © 2011 John Wiley & Sons, Ltd.
The Calcium Channel Blocking and Phosphodiesterase Inhibitory Activities of the Extract of Andropogon muricatus Explains its Medicinal Use in Airways Disorders
Authors: Shah Abdul Jabbar , Gilani Anwarul Hassan
Published: December 2011

The present work was carried out to provide a pharmacological base for the medicinal use of Andropogon muricatus in airways disorders, such as asthma. In isolated guinea‐pig tracheal strips, the crude extract of Andropogon muricatus exhibited a non‐specific relaxant effect against carbachol (1 µ m) and high K+ precontractions, with EC50 values of 0.10 (0.07–0.11) and 0.15 mg/mL (0.11–0.18), respectively, similar to papaverine, while verapamil was more potent against high K+. This suggests the involvement of a non‐specific relaxant effect, mediated possibly through Ca++ channel blockade and phosphodiesterase inhibition. The functional nature of the relaxant effect was further confirmed through indirect evidence when pretreatment of the tissues with the plant extract caused potentiation of the isoprenaline inhibitory response curves, similar to papaverine, while the effect of verapamil remained unchanged. These data indicate that the crude extract of Andropogon muricatus contains constituent(s) that mediate the tracheal relaxant effect, possibly through dual inhibition of Ca++ channels and phosphodiesterase and provide pharmacological evidence for its medicinal use in airways disorders, particularly asthma. Copyright © 2011 John Wiley & Sons, Ltd.
DFT studies of cobalt hydride intermediate on cobaloxime‐catalyzed H2 evolution pathways
Authors: Jiang Yan‐Ke , Liu Jian‐Hui
Published: December 2011

Chemical, electrochemical, and photochemical methods all had been utilized to explore proton reduction catalysis by cobaloxime complexes. It was postulated in these studies that the initial step toward making H2 was protonation of CoI to form a CoIII hydride intermediate. However, in the following steps, different results from electrochemical studies had led to both monometallic and bimetallic pathways. In this article, theoretical computation method (BP86/6‐31G*) was firstly performed on possible cobalt hydride intermediates involved in the reactive pathway of cobaloxime‐catalyzed H2 evolution. The monometallic pathway B was excluded, both monometallic pathway A and bimetallic pathway were the possible process. However, the Gibbs free energy change for generation of H2 following monometallic pathway A was much more negative than that following bimetallic pathway. The calculation on monometallic pathway A indicated that the main driving force of the reaction (i) came from the step of the reduction of 11. The proton transfer steps were also studied in detail. The protonation of cobalt hydride intermediates could directly happen on the dimethylglyoximate part. All the results refer to gas‐phase calculations, not considering the solution. © 2011 Wiley Periodicals, Inc. Int J Quantum Chem, 2011
Mass spectrometric quantification of AcSDKP‐NH2 in human plasma and urine and comparison with an immunoassay
Authors: Mesmin Cédric , Cholet Sophie , Blanchard Anne , Chambon Yann , Azizi Michel , Ezan Eric
Published: December 2011

RATIONALE

Precise assessment of renal glomerular filtration rate (GFR) is essential for the early detection of chronic kidney disease. AcSDKP‐NH2, an analogue of the endogenous tetrapeptide AcSDKP, is not degraded in vivo and is freely filtered by the kidney and eliminated in urine; for that reason this analogue is an ideal candidate marker for the assessment of GRF after administration to humans. Proof‐of‐concept demonstration and lack of toxicity in animals have allowed an ongoing clinical study in which AcSDKP‐NH2 was administered intravenously at a dose of 100 µg and compared with currently available GFR markers. The use of the AcSDKP analogue in clinical practice requires that this novel marker be associated with an analytical method that combines specificity, robustness and high accuracy. We have developed a liquid chromatography/tandem mass spectrometry (LC/MS/MS) assay and compared it with an existing enzyme immunoassay (EIA) for AcSDKP‐NH2.

METHODS

Human urine and plasma samples from the clinical study were analyzed by EIA and LC/MS/MS. Before LC/MS/MS assessment, AcSDKP‐NH2 was extracted using mixed‐mode cation‐exchange solid‐phase extraction cartridges. Chromatographic separation was performed by hydrophilic interaction liquid chromatography (HILIC), before analysis with an electrospray ionization triple quadrupole mass spectrometer.

RESULTS

Mass spectrometry, through the use of an internal standard, tailored sample preparation and chromatographic separation, has better intra‐ and inter‐assay precision (accuracies between 95 and 101% with CVs < 8% for LC/MS/MS vs. accuracies between 90 and 115% with CVs <18% for EIA) and allows greater steadiness in intra‐subject concentrations during the infusion (4.4% for LC/MS/MS vs. 8.6% for EIA). Moreover, the LC/MS/MS assay circumvents matrix effects observed in certain instances for the EIA and which may reduce its accuracy.

CONCLUSIONS

Although the EIA can provide sufficient information in most subjects, the LC/MS/MS assay associated with this new marker should be the reference method. Copyright © 2011 John Wiley & Sons, Ltd.
Detecting case–control expression quantitative trait loci using locally most powerful or maximin robust rank tests
Authors: Yuan Ao , Xu Jinfeng , Yue Qingqi , Zheng Gang
Published: December 2011

In testing genome‐wide gene expression quantitative trait loci, efficiency robust statistical methods and their computational convenience are most relevant. For this purpose, we propose to use a modified locally most powerful rank test for the analysis of case–control expression data. This modified rank test statistic is computationally simple, robust for non‐normally distributed expression data, and asymptotically locally most powerful. It depends on the specification of a location distribution form for data but is not sensitive to misspecifications. When such a location distribution form cannot be specified, we apply Gastwirth's maximin efficiency robust rank test to gene expression data to maximize the worst Pitman asymptotic relative efficiency among a family of location distributions. We conduct simulation studies to assess their performance and use an application to real data for illustration. Copyright © 2011 John Wiley & Sons, Ltd.