bluuebunny/crossref_metadata_2025 huggingface dataset:
Brillouin effect characterization in all‐Raman amplified 4 × 40 Gb/s WDM system
Authors: Pontes M. J. , Segatto M. E. V. , Barbero A. P. L. , Rocco Giraldi M. T. M. , Rocha A.M. , Neto B. , Costa J. C. W. , Martinez M. A. G. , Frazao O. , Baptista J. M. , Salgado H. , Teixeira A. L. J. , André P. S.
Published: March 2012

This article analyzes experimentally the limitations observed in a 45 km Raman amplified 4 × 40 Gb/s transmission system operating under multiple pump and single high pump power configurations. A signal‐to‐noise ratio of 19.2 dB, an extinction ratio of 10.4 dB and a jitter of 1097 fs are achieved for moderate pump powers and higher order stimulated Brillouin scattering lines give rise to system degradation for pump power levels more than 0.5 W. © 2012 Wiley Periodicals, Inc. Microwave Opt Technol Lett 54:1403–1407, 2012; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.26827
Fiber optic Fabry‐Perot interferometer based sensor for inspecting cleaved fiber ends
Authors: Kihara Mitsuru , Watanabe Hiroshi , Tanaka Masanori , Toyonaga Masanobu
Published: March 2012

We propose a novel fiber optic sensor for inspecting cleaved optical fiber ends based on Fabry–Perot interferometer.The sensor uses mainly laser diodes, an optical power meter, 3‐dB coupler, and XY lateral adjustment fiber stage. Experimentally obtained fiber end images were in good agreement with scanning electron microscope observation images. © 2012 Wiley Periodicals, Inc. Microwave Opt Technol Lett 54:1541–1543, 2012; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.26829
Baseband complexity comparison of six‐, five‐, and four‐port receivers
Authors: Östh Joakim , Karlsson Magnus , Owais Owais , Serban Adriana , Gong Shaofang
Published: March 2012

The use of six‐port correlators to implement six‐port receivers has been intensively studied. The six‐port receiver can also be modified to a five‐port or a four‐port receiver. However, the six‐, five‐, or four‐port receiver solution requires different baseband processing to recover the baseband In‐phase (I) and Quadrature‐phase (Q) data. A unified mathematical model for the six‐, five‐ and four‐port receivers is presented in this article. Possible solutions to recover the baseband data are discussed and compared. The investigation shows that the six‐port receiver has advantages over the five‐ and four‐port receivers in terms of complexity when analog baseband processing is used. Simulations are conducted to verify the model and to estimate the error vector magnitude versus frequency; the simulation also shows that the six‐port receiver operates over a wider bandwidth than the five‐ or four‐port receiver. © 2012 Wiley Periodicals, Inc. Microwave Opt Technol Lett 54:1502–1506, 2012; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.26833
A novel compact dual‐band antenna for WLAN applications
Authors: Li R.‐H. , Shi X.‐W. , Zhang N. , Wang Y.‐F. , Wang Y.‐J.
Published: March 2012

A novel compact printed monopole antenna for wireless local area network (WLAN) applications is presented in this article.The proposed antenna consists of an L‐shaped monopole radiator and an arc‐shaped stub which can produce the required two bandwidths respectively. This antenna, fed by a 50‐Ω microstrip line, has a small size of only 20 mm × 25 mm. A prototype of the dual‐band antenna has been designed, fabricated and measured. Experimental results show that the presented antenna covers 2.2–2.6 GHz and 4.7–6.2 GHz with return loss less than −10 dB. Besides, the antenna has good radiation patterns in both E and H planes. © 2012 Wiley Periodicals, Inc. Microwave Opt Technol Lett 54:1476–1479, 2012; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.26834
Silicon waveguide racetrack resonators with 1.5 μm radius using junction offsets
Authors: Fan Guofang , Sang Wei , Liu Xinhou , Zhen Zhen
Published: March 2012

We demonstrate straight and bent silicon waveguide junctions using the junction offsets.More than 20% reduction (about 0.02 dB) of the junction connection losses are obtained for the junction using 25 nm offset with bent radii 1.5 μm, compared with the junction without the offset. We also show that the performance of the silicon waveguide racetrack resonators can be improved by introducing a lateral offset at the straight‐to‐bent waveguide junctions. About 0.5 dB increase in drop power is observed for the racetrack resonators with junction offset. © 2012 Wiley Periodicals, Inc. Microwave Opt Technol Lett 54:1470–1471, 2012; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.26836
Rhombic slot antenna design with a pair of straight strips and two ∩‐shaped slots for WLAN/WiMAX applications
Authors: Xie J.‐J. , Ren X.‐S. , Yin Y.‐Z. , Zuo S.‐L.
Published: March 2012

A novel multiband rhombic slot antenna with a truncated corner is proposed for wireless local area network (WLAN) and worldwide interoperability for microwave access (WiMAX) applications simultaneously. By introducing a pair of straight strips and two etched ∩‐shaped slots, the proposed antenna can operate in multibands. The prototype of the proposed antenna has been successfully constructed and tested. The 10 dB return loss bandwidths of them are 550 MHz (3.15–3.70 GHz) and 920 MHz (5.05–5.97 GHz), respectively, which can cover both the WLAN bands (5.15–5.35 GHz and 5.725–5.825 GHz) and the WiMAX bands (3.4–3.6 GHz and 5.25–5.85 GHz). In addition, good monopole‐like radiation characteristics with sufficient antenna gains are obtained over the operating bands. © 2012 Wiley Periodicals, Inc. Microwave Opt Technol Lett 54:1466–1469, 2012; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.26837
Nanosecond response electro‐optic switch based on high cost‐effective poled polymeric material
Authors: Jin Lin , Cao Zijian , Meng Jie , Ma Chunsheng , Zhang Daming
Published: March 2012

Low cost materials and fabrication techniques are requited for the high cost‐effective optical devices in the field of the optical communication. In this article, a polymer electro‐optic switch operating at 1550 nm has been designed and fabricated. Such a switch is based on a low‐cost guest‐host material by using Disperse Red 1 (DR1) as the guest and poly(methyl methacrylate) (PMMA) as the host. DR1/PMMA can be synthesized easily. An optimal waveguide structure has been proposed. With the coplanar waveguide electrodes and corona poling, a push–pull switch device is achieved. The switch rise time and fall time are 5 and 7 ns, respectively. The insertion loss of the device (3.7‐cm length) is less than 20 dB. © 2012 Wiley Periodicals, Inc. Microwave Opt Technol Lett 54:1537–1541, 2012; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.26839
Study of a novel U‐shaped monopole UWB antenna by transfer function and time domain characteristics
Authors: Gao G. P. , Yang M.K. , Niu S. F. , Zhang J. S.
Published: March 2012

A novel U‐shaped monopole antenna suitable for ultrawideband (UWB) application is presented and investigated in this article. The antenna is developed from printed circular disc monopole antenna, and the current distribution evident that the proposed antenna has a similar current. Three steps in ground plane is designed and adjusted to obtain UWB impedance matching. Experimental results show that the proposed antenna meets the requirement of wide working bandwidth of 3.1–10.6 GHz with VSWR < 2. Study of transfer function (magnitude of S21/group delay) and time domain characteristic (waveform/fidelity) indicate a good UWB application behavior for the antenna. The proposed antenna has a compact size, good radiation characteristics, ultra wide bandwidth, and good time‐domain behaviors to satisfy the requirement of the current wireless communications systems. © 2012 Wiley Periodicals, Inc. Microwave Opt Technol Lett 54:1532–1537, 2012; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.26840
A double‐layered printed dipole antenna with parasitic strips
Authors: Zhu Quanjiang , Yang Shiwen , Huang Ming , Nie Zaiping
Published: March 2012

A broadband double‐layered printed dipole antenna with parasitic strips is presented.The printed dipole uses a double‐layered structure and is fed by an integrated strip‐line balun. Two pairs of parasitic strips are attached around the dipole to expand the impendence and pattern bandwidth. Measurement results show that the proposed antenna achieves 75% impendence bandwidth (VSWR < 2), operating between 2.5 and 5.5 GHz. Moreover, stable radiation patterns with 6.3–9.1 dBi peak gain and low cross‐polarization are obtained within the bandwidth. An eight‐element printed dipole antenna array is assembled and measured, showing a good performance in the array. © 2012 Wiley Periodicals, Inc. Microwave Opt Technol Lett 54:1517–1520, 2012; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.26841
A novel broad and multiband frequency selective surface
Authors: Ray Arup , Kahar Manisha , Sarkar Sushanta , Biswas Sushanta , Sarkar Debashree , Sarkar Partha P.
Published: March 2012

Simulated theoretical results and experimental verifications are presented for a Frequency selective surface with slotted, perfectly conducting square patch elements.The frequency selective surface (FSS) structure acts like a band‐reject filter having three broad stop bands in parts of C, X, and Ku band. Due to symmetrical nature of the design, the FSS is insensitive to variations of RF incidence angle for 90° rotations of the FSS. Simulated theoretical investigations are done by Ansoft Designer® software. Experimental investigation is performed using standard microwave test bench. © 2012 Wiley Periodicals, Inc. Microwave Opt Technol Lett 54:1353–1355, 2012; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.26843
A design method for patch antennas with wide frequency tunable range and stable conical radiation
Authors: Tsai Jia‐Fu , Shih Chuang‐Jiashih , Row Jeen‐Sheen
Published: March 2012

A design for patch antennas with a wide‐frequency tuning range is presented. The antenna structure is composed of a top‐loaded monopole and a parasitic shorted ring patch. With a variable capacitor and a microstrip exponentially tapered line, the operating frequency of the antenna can be tuned between two parallel resonant modes, both of which have symmetrical conical radiations. The key parameters of the proposed design are investigated for obtaining a maximum tuning range. A design procedure is also given. The results obtained demonstrate that the proposed antenna design can offer a frequency tuning range of more than 50%, and its radiation is stable within the range. © 2012 Wiley Periodicals, Inc. Microwave Opt Technol Lett 54:1441–1445, 2012; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.26846
Passively mode‐locked soliton fiber laser using a combination of saturable absorber and nonlinear polarization rotation technique
Authors: Shahabuddin N. S. , Mohamad H. , Mahdi M. A. , Yusoff Z. , Ahmad H. , Harun Sulaiman Wadi
Published: March 2012

All‐fiber passively mode‐locked (ML) soliton fiber laser is demonstrated based on the combination of two ML mechanisms, single wall carbon nanotube saturable absorber, and nonlinear polarization rotation.The gain medium is a 10‐m long erbium‐doped fiber, which is pumped by a 980‐nm laser diode in a ring configuration. A stable soliton laser is succesfully achieved using the filter, which functions to reshape and maintain the soliton pulse in the cavity. It operates at 1588 nm with a repetition rate of 8.3 MHz and a pulse width of 0.79 ps. The output spectrum shows strong Kelly sidebands indicating that the pulse duration is near the minimum possible value. © 2012 Wiley Periodicals, Inc. Microwave Opt Technol Lett 54:1430–1432, 2012; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.26850
Broadband CPW‐fed circularly polarized square slot antenna with inverted‐L strips for wireless applications
Authors: Rezaeieh Sasan Ahdi , Kartal Mesut
Published: March 2012

This article proposes an impressive design of a circular polarized square slot antenna (CPSSA). The proposed single layer antenna composed of a square ground plane embedded with three unequal sized inverted‐L strips around corners, which are capable of generating a resonant mode for exciting two orthogonal E vectors. Compared to the previous similar CPSSA designs, the axial‐ratio bandwidth of the antenna is increased, more than two times. The designed CPSS antenna with its compact 40 × 40 × 0.8 mm3 size operates over the frequency band between 2.63 and 6.38 GHz for VSWR<2 exhibiting a 71.11% (3–6.1 GHz) circular polarization (CP) bandwidth. Throughout this letter, the improvement process of the axial ratio and S11 properties are presented and discussed in detailed. © 2012 Wiley Periodicals, Inc. Microwave Opt Technol Lett 54:1399–1402, 2012; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.26851
An optical homodyne instrument for simultaneously measuring the dual‐wavelength optical phase variations
Authors: Twu Ruey‐Ching , Hou Hong‐Yao
Published: March 2012

A novel homodyne metrology is demonstrated to simultaneously measure the dual‐wavelength optical phase variations in a common‐path polarization interferometer.The homodyne light sources were provided by launching the incident lights with different wavelengths into a same lithium niobate Zn‐indiffused phase modulator. The LabVIEW‐based instrument provides flexible signal processing and real‐time data display for the measured results. © 2012 Wiley Periodicals, Inc. Microwave Opt Technol Lett 54:1464–1466, 2012; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.26855
Third order integrable UHF bandpass filter using active inductors
Authors: Colucci Paolo , Leuzzi Giorgio , Pantoli Leonardo , Stornelli Vincenzo
Published: March 2012

In this article, an UHF third order bandpass filter based on an high‐Q active inductor (AI) is described and measurement results, performed on a prototype board, are presented and compared with software simulations. The designed AI includes a passive variable phase‐ and amplitude‐compensating network and a highly linear inverting amplifier, forming a gyrator‐C architecture that gives to the filter also frequency and amplitude tuneability proprieties. The fabricated Butterworth filter has a center frequency of 600 MHz and a measured noise figure of 11 dB with a 5 dBm 1‐dB compression point and a 82 dB dynamic range. All passive components values have been chosen to allow the circuit to be completely integrated in a standard IC design. © 2012 Wiley Periodicals, Inc. Microwave Opt Technol Lett 54:1426–1429, 2012; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.26857
Design and modeling of a high gain wideband circular polarized dielectric resonator antenna array
Authors: Ain M. F. , Qasaymeh Y.M. , Ahmad Z. A. , Zakariya M. A. , Othman M. A. , Abdullah M. Z.
Published: March 2012

In this letter, a circular polarized dielectric resonator antenna (DRA) using notched resonators excited through narrow slots is presented. To improve the gain, the slot positions were determined based on the characteristic of standing wave ratio over a short ended microstrip feeder. To enhance the bandwidth and circular polarization, three notched rectangular dielectric elements were rotated 45° with respect to the sides of the exciting slots. The DRAs are modeled as a parallel RLC component, as that will be used to determine the dielectric resonator dimensions. Antenna characteristics of the array antenna including return loss, radiation patterns, and antenna gain are presented. The size of the whole antenna structure is 40 × 45 mm2 which gives its potential use in wireless communication systems. © 2012 Wiley Periodicals, Inc. Microwave Opt Technol Lett 54:1396–1399, 2012; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.26860
A novel compact dual band‐notched slot antenna for ultrawideband applications
Authors: Emadian Seyed Ramin , Ghobadi Changiz , Nourinia Javad
Published: March 2012

A compact dual band‐notch ultra‐wideband circle‐like slot antenna fed by coplanar waveguide line is proposed.The U‐ and L‐shaped slots are used to create dual‐band notch characteristics. The antenna is as small as 26 × 26 × 1.6 mm3. The designed antenna offers a wide bandwidth from 2.75 to 14.2 GHz (135%), defined by VSWR < 2, with two notched bands, covering all the 5‐/6‐GHz WLAN, 3.5‐/5.5‐GHz WIMAX and 4‐GHz C bands. An equivalent circuit model of the antenna is presented to discuss the mechanism of the dual band‐notched UWB antenna. Impedance, radiation, and gain characteristics of the proposed antenna are also discussed. © 2012 Wiley Periodicals, Inc. Microwave Opt Technol Lett 54:1365–1368, 2012; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.26862
A multiband hybrid antenna with double layer structures for mobile devices
Authors: Sim Chow‐Yen‐Desmond , Chao Chun‐Heng , He Wen‐Bin
Published: March 2012

The design of a hybrid antenna with double layer structures that allow multiband operation in the global system for mobile communications/digital communication systems/personal communication system/universal mobile telecommunications system and wireless local area network band bands is presented. By combining the resonant modes excited separately by the upper layer planar inverted‐F antenna structure (0.88, 0.97, and 1.18 GHz) and lower layer monopole antenna type structure (1.38, 1.76, and 2.45 GHz), a dual‐frequency operation with broadband characteristics can be observed, whereby the lower and upper frequency bands are operating between 0.86 and 1.00 GHz and between 1.15 and 2.63 GHz, respectively. From the experimental results, stable gain and good radiation efficiency are also exhibited within the bands of interest. © 2012 Wiley Periodicals, Inc. Microwave Opt Technol Lett 54:1543–1548, 2012; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.26863
Altered autophagy gene expression and persistent atrophy suggest impaired remodeling in chronic hemiplegic human skeletal muscle
Authors: von Walden Ferdinand , Jakobsson Finnbogi , EdstrÖm Lars , Nader Gustavo A.
Published: March 2012

Introduction:

Upper motor neuron lesions after stroke are a major cause of disability. We aimed to determine whether skeletal muscles from these patients display typical molecular signatures of inflammation, growth arrest, and atrophy.

Methods:

Muscle biopsies were analyzed for morphological, histochemical, ultrastructural, and molecular features indicative of changes in gene expression involved in muscle atrophy.

Results:

Chronic hemiplegia resulted in ∽9.5% atrophy, fiber type shifts, and histochemical and ultrastructural signs of impaired remodeling. TNF and TWEAK expressions were unaltered, but MSTN mRNA was lower (−73%, P < 0.05) in paretic tibialis anterior vs. age‐matched controls. The expression of autophagy‐related genes (BCN‐1, LC3, and GABARAPL1) was lower in paretic tibialis anterior (−81%, −48%, and −60%, respectively, P < 0.01) and soleus (−85%, −54%, and −60% respectively, P < 0.01) compared with old controls.

Conclusions:

Persistent atrophy in chronic spastic hemiplegia may be associated with impaired remodeling partly due to altered autophagy gene expression. Muscle Nerve, 2012
Paleopathological and Molecular Study on Two Cases of Ancient Childhood Leprosy from the Roman and Byzantine Empires
Authors: Rubini Mauro , Erdal Yilmaz S. , Spigelman Mark , Zaio Paola , Donoghue Helen D.
Published: March 2012

This study is based on the paleaopathology of leprosy on human skeletal remains and the detection of ancient Mycobacterium leprae DNA. Two cases of childhood leprosy were recognized. The first case was in a Roman necropolis at Martellona (Rome, Central Italy), dated to the 2nd to 3rd centuries ce. The skeleton of a child aged 4–5 years, from tomb 162, is the youngest individual in Italy from this time period, with the clear rhino‐maxillary syndrome and other bony changes indicative of leprosy. The second case from a burial at Kovuklukaya, in the Sinop region of Northern Turkey, was from the 8th to the 10th centuries, during the Byzantine era. The endocranium of a 4–5‐month‐old infant with new bone formation—an indication of chronic inflammation—was positive for M. leprae DNA. Infant and childhood leprosy is uncommon today, and there is a scarcity of information in the osteoarchaeological literature of leprosy in the past, especially in children. The significance of these cases is that it adds to an understanding of the history of the disease in the former Roman Empire. It is hoped that over time sufficient data can be obtained to understand the epidemiological dynamics and clinical evolution of leprosy from the ancient period until today. Copyright © 2012 John Wiley & Sons, Ltd.
Perceptions of Mentoring of Full‐Time Occupational Therapy Faculty in the United States
Authors: Falzarano Mary , Zipp Genevieve Pinto
Published: March 2012

The purpose of this study was to describe the occurrence, nature and perception of the influence of mentoring for full‐time occupational therapy faculty members who are on the tenure track or eligible for re‐appointment in the United States. An online survey was sent during 2010 September, the beginning of the academic year, to all 818 potential participants in the United States entry‐level and doctoral programmes. Fifty six of 107 participants who met the criteria reported being in a mentoring relationship and positively rated their perception of the influence of mentoring on academic success and academic socialization. The response of all participants to open‐ended questions describes preferred mentoring characteristics (providing information, support), benefits (having someone to go to, easing the stress) and challenges (not enough time, mentoring not valued). Findings inform current and potential faculty of the current state of mentoring. Administrators can use this information when designing mentoring opportunities, educating mentors and mentees about the mentoring process, arranging mentors/mentees release time for engaging in the mentoring process and finally, managing the mentor/mentee needs. The cross‐sectional survey of the United States occupational therapy faculty limits generalizability yet paves the way for future studies to explore retention and recruitment of mentored faculty across countries. Copyright © 2012 John Wiley & Sons, Ltd.
Surgical management of complications of multimodal therapy
Authors: Chui Chan‐Hon
Published: March 2012

Multimodality therapies that include surgery, chemotherapy, radiotherapy, and various newer forms of targeted therapies have been commonly applied in childhood cancers. Such modalities are associated with complications that may adversely affect the outcome of cancer treatment. Acute complications that require surgical management form the focus of our discussion. These patients are often compromised by immunosuppression, thrombocytopenia, and malnutrition. The complications discussed include typhlitis, invasive aspergillosis (IA), pancreatitis, hemorrhagic cystitis, gastrointestinal hemorrhage, necrotizing skin and soft‐tissue infections, and perianal infection. Familiarity with the spectrum of complications and their appropriate management approaches will minimize the patients' morbidity. Pediatr Blood Cancer 2012;59:405–409. © 2012 Wiley Periodicals, Inc.
Synthesis and antimicrobial activity of the Schiff base from polyoxyalkylene‐montmorillonite nanocomposites and aldehydes
Authors: Salahuddin Nehal , Badr Badr , Abdeen Rehab
Published: March 2012

Vanillin (4‐hydroxy‐3‐methoxy benzaldehyde) and 5‐formylamino salicylic acid microbicides were reacted with polyoxyalkylene‐montmorillonite (D230–2000‐MMT) nanocomposites. The microstructure of these Schiff base nanocomposites was characterized by TEM and XRD. D230–2000‐MMT nanocomposites were prepared by an ion exchange process of sodium montmorillonite (Na‐MMT) and NH3
+ groups in polyoxyalkylene amine hydrochloride with three different molecular masses of D230, D400, and D2000. Wide‐angle X‐ray diffraction confirms the intercalation of the polymer between the silicate layers. Electrostatic interaction between the positively charged NH3
+ groups and the negatively charged surface of MMT was observed. The nanocomposites were tested for antimicrobial activity against the Gram‐negative bacteria (Escherichia coli NCIM 2065), Gram‐positive bacteria (Bacillus subtillus ATCC), and fungi (Candida albicans SC5314 and Cryptococcus neoformans). The D2000‐MMT/vanillin Schiff base nanocomposite strongly inhibited the growth of all microorganisms that can be used in different applications. The amount of loaded polymer and the structure of the nanocomposite play an important role in inhibiting the bacterial and fungal strains. It is found that the Schiff base nanocomposite affect the morphology, oxygen consumption, and the release of cytoplasmic constituents such as potassium (K+), sodium (Na+), and calcium (Ca2+) ions leading to death of the cells. POLYM. COMPOS., 2012. © 2012 Society of Plastics Engineers
Dielectric properties of nanographite‐filled PMMA composites prepared by in situ polymerization
Authors: Singhi Manasi , Fahim M.
Published: March 2012

In this work, a series of polymer composites was prepared by in situ polymerization of methylmethacrylate (MMA) as a monomer and sonicated nanographite particles (∼400 nm) as conductive fillers. The concentration of nanographite particles was changed in the step of 0.25 wt% in the monomer and five composites having a filler concentration of 0.25, 0.50, 0.75, 1, and 1.5 wt% respectively were prepared. The composites were characterized for their morphology, thermal, and dielectric behavior. Room temperature dielectric behavior of the composites was studied at six different frequencies of 100 Hz, 1, 10, 100, 500 kHz, and 1 MHz. Temperature‐dependent dielectric properties was studied in the temperature range from 30 to 150°C at the above frequencies. It was interesting to note that at room temperature dielectric constant (ε′) decreased with increasing concentration of nanographite and reached a minimum at a filler concentration of 0.75 wt%. Dielectric relaxation behavior was observed in the temperature versus tan δ curves. The dielectric peak shifted to higher temperatures with increase in frequency and vice‐versa. POLYM. COMPOS., 2012. © 2012 Society of Plastics Engineers
Use of eco‐friendly epoxy resins from renewable resources as potential substitutes of petrochemical epoxy resins for ambient cured composites with flax reinforcements
Authors: Bertomeu D. , García‐Sanoguera D. , Fenollar O. , Boronat T. , Balart R.
Published: March 2012

In the last years, some high renewable content epoxy resins, derived from vegetable oils, have been developed at industrial level and are now commercially available; these can compete with petroleum‐based resins as thermoset matrices for composite materials. Nevertheless, due to the relatively high cost in comparison to petroleum‐based resins, their use is still restricted to applications with relatively low volume consumption such as model making, tuning components, nautical parts, special effects, outdoor sculptures, etc. in which, the use of composite laminates with carbon, aramid and, mainly, glass fibers is generalized by using hand layup and vacuum assisted resin transfer molding (VARTM) techniques due to low manufacturing costs and easy implementation. In this work, we study the behavior of two high renewable content epoxy resins derived from vegetable oils as potential substitutes of petroleum‐based epoxies in composite laminates with flax reinforcements by using the VARTM technique. The curing behavior of the different epoxy resins is compared in terms of the gel point and exothermicity profile by differential scanning calorimetry (DSC). In addition, overall performance of flax‐epoxy composites is compared with standardized mechanical (tensile, flexural and impact) and thermal (Vicat softening temperature, heat deflection temperature, thermo‐mechanical analysis) tests. The curing DSC profiles of the two eco‐friendly epoxy resins are similar to a conventional epoxy resin. They can be easily handled and processed by conventional VARTM process thus leading to composite laminates with flax with balanced mechanical and thermal properties, similar or even higher to a multipurpose epoxy resin. POLYM. COMPOS., 2012. © 2012 Society of Plastics Engineers
Characterization of interfacial toughness in carbon fiber/epoxy resin composite subjected to water aging using single‐fiber fragmentation method in an energy‐based model
Authors: Liu Hongxin , Gu Yizhuo , Li Min , Zhang Zuoguang
Published: March 2012

The toughness of the interphase between carbon fibers and epoxy resin was characterized by the interfacial fracture energy, which was derived from the modified Wagner‐Nairn‐Detassis (WND) model, considering the moisture swelling stress. The characterization was used to evaluate the changes of interphase bonding before and after water aging, including boiling water and 70°C water immersion. The effects of the water aging on the parameters in WND model were analyzed. The mechanism of interphase degradation under water aging was interpreted considering the change of interphase thickness, which was measured using the dynamic nanomechanical mapping method. It is shown that the single‐fiber fragmentation test with the proposed energy‐based model can quantify the degradation of interphase toughness after water aging. For the studied system, the interphase thickness has a close relationship with the interfacial fracture energy, indicating that the swelling of the resin matrix and interphase results in an increase in interphase thickness and a decrease in interphase bonding property. POLYM. COMPOS., 2012. © 2012 Society of Plastics Engineers
Processing of Unjust and Just Information: Interpretation and Memory Performance Related to Dispositional Victim Sensitivity
Authors: Baumert Anna , Otto Kathleen , Thomas Nadine , Bobocel D. Ramona , Schmitt Manfred
Published: March 2012

With two studies, we tested whether dispositional victim sensitivity involves one of two kinds of biased processing style: either a processing style in which unjust—but not just—information is processed more readily and accurately than neutral information or a processing style in which unjust and just information is processed preferentially over neutral information. In Study 1, victim sensitivity increased the speed with which participants resolved ambiguous sentence fragments in cases in which the resolution yielded an unjust connotation, as well as in cases in which the resolution yielded a just connotation, but not when the resolution was neutral with respect to justice. In Study 2, persons high in victim sensitivity displayed enhanced memory performance for both unjust and just information relative to neutral information over a 1–week retention interval. The results are consistent with the assumption that victim sensitivity is characterized by the activation potential and elaboration of both injustice and justice concepts. Our findings are important for the understanding of how the fear of being exploited among victim–sensitive persons shapes antisocial behaviour. Copyright © 2012 John Wiley & Sons, Ltd.
Trait Self–Esteem Moderates Decreases in Self–Control following Rejection: An Information–Processing Account
Authors: vanDellen Michelle , Knowles Megan L. , Krusemark Elizabeth , Sabet Raha F. , Campbell W. Keith , McDowell Jennifer E. , Clementz Brett A.
Published: March 2012

In the current paper, the authors posit that trait self–esteem moderates the relationship between social rejection and decrements in self–control, propose an information–processing account of trait self–esteem's moderating influence and discuss three tests of this theory. The authors measured trait self–esteem, experimentally manipulated social rejection and assessed subsequent self–control in Studies 1 and 2. Additionally, Study 3 framed a self–control task as diagnostic of social skills to examine motivational influences. Together, the results reveal that rejection impairs self–control, but only among low self–esteem individuals. Moreover, this decrement in self–control only emerged when the task had no social implications—suggesting that low self–esteem individuals exert effort on tasks of social value and are otherwise preoccupied with belonging needs when completing nonsocial tasks. Copyright © 2012 John Wiley & Sons, Ltd.
The influence of the internal structure of core–shell particles on poly(vinyl chloride)/(methyl methacrylate–butadiene–styrene) blends
Authors: Zhou Chao , Qi Xiaoxue , Gao Yun Xia , Sun Shulin , Zhang Huixuan
Published: March 2012

Methyl methacrylate–butadiene–styrene (MBS) core–shell particles were prepared by grafting styrene and methyl methacrylate onto polybutadiene seeds via emulsion polymerization. All the MBS particles were designed with the same chemical composition, similar grafting degree but different internal structures. The difference in internal structure was realized by controlling the ratio of ‘external grafting’ and ‘internal grafting’ of styrene. The work focused on the influence of the internal structure of MBS core–shell particles on the properties of poly(vinyl chloride)/MBS blends. From transmission electron microscopy, three different internal structures were observed: rare sub‐inclusions, a large number of small sub‐inclusions and large sub‐inclusions. The results of dynamic mechanical analysis illustrated that the different internal structures greatly affected the glass transition temperature Tg of the rubber phase and the storage modulus of the core–shell particles. The notched Izod impact test results showed that the MBS with large sub‐inclusions had the lowest brittle–ductile transition temperature, while the transparency test revealed that the presence of sub‐inclusions in the rubbery phase reduced the transparency of the blend. Copyright © 2012 Society of Chemical Industry
Origin and Flow Dynamics of Perennial Groundwater in Continuous Permafrost Terrain using Isotopes and Noble Gases: Case Study of the Fishing Branch River, Northern Yukon, Canada
Authors: Utting Nicholas , Clark Ian , Lauriol Bernard , Wieser Martin , Aeschbach‐Hertig Werner
Published: March 2012

Perennially flowing groundwater discharges along a 15‐km section of the Fishing Branch River, Yukon causing open water during winter and numerous discrete springs near Bear Cave Mountain. Groundwater flow occurs in karstified marine carbonate rocks as well as in alluvial river talik(s). The PCO2 and δ13C indicate groundwater dissolves CO2 during recharge in organic soils and weathers limestone in the aquifer. These analyses show three groundwater chemistry groups and variability in surface water chemistry. The variations in water chemistry are related to differences in the rocks exposed in the recharge area. The δ18O and δ2H results show that groundwater represents approximately the annual average of precipitation based on samples collected in the region. Noble gases were used to determine that the recharge temperature lies between 0 and 5 °C which suggests that recharge happens during the summer. Groundwater ages, calculated using 3H‐3He dating, were found to be between 0 and 17.7 years. River discharge was measured during spring and summer under different water‐level conditions. Winter baseflow was calculated based on summer discharge measurements and the width of the river channel in winter. Although river flow decreases in winter, groundwater discharge maintains open water. Copyright © 2012 John Wiley & Sons, Ltd.
Antioxidant Peptides from Protein Hydrolysate of Microalgae Navicula incerta and their Protective Effects in Hepg2/CYP2E1 Cells Induced by Ethanol
Authors: Kang Kyong‐Hwa , Qian Zhong‐Ji , Ryu BoMi , Karadeniz Fatih , Kim Daekyung , Kim Se‐Kwon
Published: March 2012

Marine microalgae have been reported as valuable new sources of pharmacologically active compounds and there are now numerous commercial applications of microalgae. Hence, in this study we evaluated the protective effects of peptides purified from marine microalgae, Navicula incerta, against alcohol‐induced damage in HepG2/CYP2E1 cells. To obtain bioactive peptides from microalgae, N. incerta was hydrolysed using various enzymes (alcalase, α‐chymotrypsin, neutrase, papain, pepsin, pronase‐E and trypsin), and the hydrolysates were evaluated for cytoprotective activity. Among them, papain‐derived hydrolysate exhibited higher antioxidant activities than those of other enzymes. Therefore, papain hydrolysate was purified in order to obtain potent antihepatotoxic and antioxidative peptides. The amino acid sequences of the purified peptides were analysed as; NIPP‐1 (Pro‐Gly‐Trp‐Asn‐Gln‐Trp‐Phe‐Leu) with molecular mass 1 171 Da, and NIPP‐2 (Val‐Glu‐Val‐Leu‐Pro‐Pro‐Ala‐Glu‐Leu) with molecular mass 1108 Da. Furthermore, this study demonstrated that NIPP‐1 and NIPP‐2 peptides inhibited ethanol‐induced cytotoxicity in HepG2/CYP2E1 cells. Copyright © 2012 John Wiley & Sons, Ltd.
Adaptive notch filter for synchronization and islanding detection using negative‐sequence impedance measurement
Authors: Tuyen Nguyen Duc , Fujita Goro , Funabashi Toshihisa , Nomura Masakatsu
Published: March 2012

Dispersed generation (DG) has been found promising for satisfying the requirements of high power quality in distributed systems. One operation situation, namely, an island, is formed when one or more DG systems and an aggregate of local loads are disconnected from the main grid and remain operational as an islanded entity. Islanding is either due to intentional events, e.g. maintenance outage, or due to unintentional events, such as faults, and their subsequent switching actions. Islanding is usually undesirable because of the potential harm it causes to the existing equipment, human safety, power reliability and quality, etc. Accordingly, anti‐islanding schemes are used to immediately detach a DG system from the feeder after islanding. This paper presents an active method of detecting islanding for DG systems by injecting a small negative voltage into the point of common coupling, and then measuring the negative system impedance. In this study, an adaptive notch filter is introduced as a synchronous part instead of a phase‐locked loop and as a signal processing unit as well. The proposed control strategy allows DG systems to detect properly the occurrence of islanding in a balanced distribution system. Simulation results show the overall system performance including synchronization, power control, and islanding detection capability of the simulated DG system. © 2012 Institute of Electrical Engineers of Japan. Published by John Wiley & Sons, Inc.
Wavelength‐transparent IP‐over‐CWDM network with stackable ROADMs for best effort performance
Authors: Nooruzzaman Md. , Kawai Shogo , Thi Thanh Thuy Nguyen , Koyama Osanori , Katsuyama Yutaka
Published: March 2012

Stackable reconfigurable optical add/drop multiplexers (S‐ROADMs) have been proposed for use in IP over coarse wavelength‐division multiplexing (CWDM) networks so as to provide capabilities of remote lightpath reconfiguration and manual ROADM reconfiguration under the best effort transmission specified by the service level agreement. The S‐ROADM can be constructed by connecting modules with different wavelengths required in the node. The experimental results clarify that the S‐ROADM can add/drop or pass through the wavelengths successfully, providing no limit to the passing‐through (PT) wavelengths, that is, ensuring the wavelength transparency in the network. The S‐ROADMs could remove congestions by adding a lightpath remotely within a recovery time with degraded SLA. The transmission break time was also within the recovery time when adding a module manually to the in‐service S‐ROADM to increase bandwidth to be provided to new users. As a result, the S‐ROADMs provide more flexible CWDM networks in terms of scalability and reconfigurability. © 2012 Institute of Electrical Engineers of Japan. Published by John Wiley & Sons, Inc.
Effects of 4‐nonylphenol on balance of steroid and thyroid hormones in sexually immature male yellowfin seabream (Acanthopagrus latus)
Authors: Naderi Mohammad , Mousavi Seyed Mohammad , Safahieh Alireza , Ghatrami Ebrahim Rajabzade , Zargham Davood
Published: March 2012

Nonylphenol (NP) is an endocrine disrupting chemical which has been shown to be able to modulate the endocrine system of various organisms by different mechanisms. The objective of this study was to investigate the potential effects of 4‐NP on steroid and thyroid hormone levels in sexually immature male yellowfin seabream (Acanthopagrus latus), a protandrous hermaphrodite species. For this, the fish were injected with ascending doses (10, 50, 100, and 200 μg g−1 body weight) of 4‐nonylphenol (4‐NP) or vehicle during 2 weeks. After 7 and 14 days the fish were anesthetized, blood sample were collected and plasma steroid and thyroid hormone concentrations were quantified by radioimmunoassay. The result showed that 4‐NP induced a significant increase in 17β‐etradiol levels at dose 10 μg g−1, while the levels of this hormone in the higher doses decreased compared with the control group. However, 4‐NP treatment did not have any significant effect on plasma levels of testosterone. In addition, it was observed that 4‐NP affect the level of thyroid hormones in fish. Plasma thyroxine levels increased in a dose‐dependent manner after 7 and 14 days of the exposure. In contrast, a significant decrease in triiodothyronine levels was observed during the experiment period. Moreover, no significant change was detected for thyroid stimulating hormone levels in 4‐NP‐treated fish. These results indicated that 4‐NP could lead to disturb the balance of steroid and thyroid hormones with potential consequences for sexually immature male yellowfin seabream. © 2012 Wiley Periodicals, Inc. Environ Toxicol 29: 459–465, 2014.
Exploring the Use of the Interactive Systems Framework to Guide School Mental Health Services in Post‐disaster Contexts: Building Community Capacity for Trauma‐Focused Interventions
Authors: Taylor Leslie K. , Weist Mark D. , DeLoach Kendra
Published: March 2012

Over the past two decades schools have been identified as the de facto mental health system for youth. Therefore, improving and expanding school mental health (SMH) has become a pressing agenda item for researchers, practitioners, policy makers, and funders. Advancing this agenda includes not only translating intervention research into practice within schools, but building capacities for these interventions to occur. The interactive systems framework (ISF) of Wandersman and colleagues, and the focus of this special issue, provides guidance in bridging the gap between research and practice through multisystem capacity building. There is some evidence that application of the ISF has helped to build capacity for SMH in states, but this evidence is preliminary. In addition, application of the ISF has not occurred in SMH at the community level or in relation to the specific stresses a community undergoes in relation to a disaster. The purpose of this article was to conduct a preliminary attempt to connect these three areas—the ISF, SMH and strengthening SMH through the ISF to better address impacts of a community level disaster; in this case, we explore the impacts of Hurricane Katrina on New Orleans schools, their students and families, and SMH programming within them.

Special Issue: Advances in Bridging Research and Practice Using the Interactive System Framework for Dissemination and Implementation; Guest Editors: Abraham Wandersman, Paul Flaspohler, Catherine A. Lesesne, Richard Puddy; Action Editor: Emilie Phillips Smith
Current concepts of leg lengthening
Authors: Hasler Carol C. , Krieg Andreas H.
Published: March 2012

Any lower limb discrepancy may be equalised by conservative means (insoles, prosthesis and orthosis). However, their long-term acceptance is low in regard to function, costs, expenditure and appearance. Timely epiphysiodesis is the best option in uniplanar deformities with adequate remaining growth and for patients whose predicted final body height is above the 50th percentile. However, many patients present late or with multi-planar deformities, which warrant more sophisticated operative approaches. The history of surgical bone lengthening comprises 100 exciting years of struggling, development and ongoing learning. The initial strategy of acute or rapid incremental distraction had lasted almost half a century until Ilizarov recognised the benefits of biological periosteum-preserving osteotomies and incremental lengthening at slow rates (1 mm/day) at a 4 × 0.25-mm daily rhythm, well appreciated as callotasis. In parallel, ring and wire constructs made complex three-dimensional axial, translational and rotational bone moulding possible. Taylor Spatial Frames—built on hexapod strut-linked platform technology as known from flight simulators—took limb correction to a more reliable, more precise and aesthetical level, all the more that the whole process became web-based. It represents state-of-the-art methodology and technology for complex, multi-plane deformities. Due to the significant risk of secondary malalignment, indications for lengthening by unilateral fixation have shrunken to moderate amounts of length disparity and uni- to bi-planar deformities in patients with still open physes. Mechanical or motorised, minimally invasively placed nails prevent muscle fixation and, therefore, ease rehabilitation, increase patient comfort and potentially shorten the overall time of sick leave and refrain from sports activities. Hence, they offer a valuable alternative for low-grade complexity situations. It remains to be proved if the significantly higher implant costs are compensated by lower treatment costs. Overall, limb lengthening, particularly in combination with multi-planar deformity correction, can still be an arduous endeavour. In any case, wise judgement of the patient's deformity, medical and biological situation, psychosocial environment, selection of the appropriate method and hardware, as well as meticulous operating technique by an experienced surgeon are the cornerstones of successful outcomes.
Microfluidic Assay to Quantify the Adhesion of Marine Bacteria
Authors: Arpa-Sancet M. P. , Christophis C. , Rosenhahn A.
Published: March 2012

For both, environmental and medical applications, the quantification of bacterial adhesion is of major importance to understand and support the development of new materials. For marine applications, the demand is driven by the quest for improved fouling-release coatings. To determine the attachment strength of bacteria to coatings, a microfluidic adhesion assay has been developed which allows probing at which critical wall shear stress bacteria are removed from the surface. Besides the experimental setup and the optimization of the assay, we measured adhesion of the marine bacterium Cobetia marina on a series of differently terminated self-assembled monolayers. The results showed that the adhesion strength of C. marina changes with surface chemistry. The difference in critical shear stress needed to remove bacteria can vary by more than one order of magnitude if a hydrophobic material is compared to an inert chemistry such as polyethylene glycol.