bluuebunny/crossref_metadata_2025 huggingface dataset:
Wide band balun filter using open/shorted coupled line sections
Authors: Pu Xing Yu , Zhou Xin Yu , Zheng Shao Yong , Long Yun Liang
Published: March 2015

Out of phase equal power division and bandpass filtering functionalities are combined within a single circuit element over a wide bandwidth. This is achieved in the proposed structure by the use of open/shorted coupled line sections. A balun band pass filter (BPF) with a wide bandwidth of 40% is realized to validate the feasibility of the proposed structure. The measured results agree well with simulation, exhibiting small amplitude, and phase imbalance at the output ports throughout the desired passband, together with good rejection elsewhere. © 2015 Wiley Periodicals, Inc. Microwave Opt Technol Lett 57:1099–1101, 2015
Differential‐fed ultrawideband polarization diverstiy antenna with dual notch bands
Authors: Huang He , Liu Ying , Gong Shu‐Xi
Published: March 2015

A differential‐fed ultrawideband (UWB) polarization diversity antenna with dual band‐notched features is proposed in this letter for the first time. The antenna is composed of a smoothing square slot and two orthogonal differential pairs aiming to achieve polarization diversity operation across the UWB from 2 to 11 GHz. High differential port isolation of less than −40 dB is also obtained. Besides, the embedded C‐shaped slots on the main radiation elements are used to filter 5.5 GHz wireless local area network band and 8 GHz X‐band. A prototype has been manufactured and tested. Results show that the antenna will be promising for the application in UWB wireless communication systems. © 2015 Wiley Periodicals, Inc. Microwave Opt Technol Lett 57:1084–1089, 2015
Design and realization of high directivity microstrip coupler
Authors: Maheswari Shanmugam , Jayanthy Thankappan
Published: March 2015

A method to improve the directivity of the microstrip coupler is presented. The structure of the coupler is modified for variable coupling coefficient. Using this structure, the power coupled to the isolated port can be controlled which results in high directivity. Using this procedure, 15‐dB couplers are designed and fabricated at 0.9 GHz. A high directivity of 43 dB is measured. The validity of the design concept is verified by simulations and measurements. © 2015 Wiley Periodicals, Inc. Microwave Opt Technol Lett 57:1078–1081, 2015
Novel adaptive blind spot detector using square modified cantor fractal microstrip antenna array
Authors: Mondal Tapas , Roy Taniya , Ghatak Rowdra , Chaudhuri Sekhar Bhadra
Published: March 2015

This article proposes an adaptive vehicular antenna array with four analog variable phase shifters and a corporate feed network to tilt the main beam in any broadside direction and scan the blind spot zone. Square modified cantor fractal geometry of each element achieves 65% surface reduction, measured 75 MHz bandwidth, 5.5 dB gain, −32 dB return loss, and an array gain of 11 dB at 5.88 GHz dedicated short range communication service frequency band. © 2015 Wiley Periodicals, Inc. Microwave Opt Technol Lett 57:1067–1072, 2015
Ku‐band compact bandpass filter with wide upper stopband using multilayer liquid crystal polymer technology
Authors: Shen Mengkui , Shao Zhenhai , You Chang Jiang , Ban Fangsheng
Published: March 2015

An improved compact bandpass filter (BPF) with ultrawide upper stopband on three‐layer liquid crystal polymer substrate is presented. In this work, a broadside‐coupled H‐shape resonator and open circuited with radial stub are used to realize compact BPF. The first BPF is designed with three broadside‐coupled H‐shape resonators, which are placed on the top layer and middle layer, respectively. To improve the selectivity and reduce the size while not widen the bandwidth, an improved filter based on the first filter is proposed, which adds two open circuited with radial stubs and removing two H‐shape resonators. The measured results show that the second filter has better selectivity and much more compact size of 6 mm × 6 mm (about 0.52λg × 0.52λg) while keeping wide upper stopband and high rejection, comparing with the first filter, which size is 7 mm × 8 mm (about 0.61λg × 0.7λg). © 2015 Wiley Periodicals, Inc. Microwave Opt Technol Lett 57:1121–1125, 2015
Compact coplanar waveguide bandpass filter based on coupled S‐shaped split ring resonators
Authors: Horestani Ali K. , Durán‐Sindreu Miguel , Naqui Jordi , Fumeaux Christophe , Martín Ferran
Published: March 2015

This letter is focused on the application of coupled single‐layer S‐shaped split ring resonators (S‐SRRs) to the design of highly compact bandpass filters in coplanar waveguide (CPW) technology. S‐SRRs have been previously demonstrated as miniaturized resonators, particularly suited for applications in conjunction with coplanar line geometries. However, size reduction of CPW filters based on impedance inverters and S‐SRRs is limited by the inverters. Therefore, this letter proposes an alternative geometry of CPW bandpass filters employing S‐SRRs in a configuration based on the theory of coupled resonators. A highly compact third‐order bandpass filter is designed using this principle, and the proposed approach is validated through experiment, demonstrating competitive filter performance achieved in an extremely small area. © 2015 Wiley Periodicals, Inc. Microwave Opt Technol Lett 57:1113–1116, 2015
A wideband high selectivity filtering balun
Authors: Hao Zhang‐Cheng , Ding Wen‐Qi , Huo Xin‐Ping
Published: March 2015

This letter presents a wideband planar multiple‐functional balun which simultaneously has balun and filtering response. By utilizing the geometrical symmetry character of substrate integrated waveguide bandpass filter, a wideband balun is developed with high selectivity. Multiple slots are etched on the bottom and top layers to improve the isolation performance of the proposed balun. As demonstrations, an X‐band filtering balun is designed and verified by experiments. Good agreements are obtained between simulated and measured results, which show that the measured filtering balun has an operation bandwidth from 8.7 to 11.7 GHz, that is, around 30.27% fractional bandwidth, a maximum 5.6 degree output phase imbalance, and a small insertion loss of 4.1 dB at center frequency of 10.2 GHz. © 2015 Wiley Periodicals, Inc. Microwave Opt Technol Lett 57:1107–1110, 2015
High performance tunable bandpass filter with separately reconfigurable passband edges
Authors: Zhang Bo , Li Shao‐Sheng , Huang J.‐M.
Published: March 2015

A high performance tunable bandpass filter (BPF) with separately reconfigurable passband edges is presented based on a novel varactor‐tuned stepped‐impendence stub‐loaded resonator. The proposed resonator consists of three variable capacitors and a half wavelength resonator loaded with three stepped‐impendence stubs symmetrically. Theoretical expressions have been derived for the resonant frequencies. Each passband edge can be reconfigured by adjusting capacitance values of the capacitors loaded on the stubs. High performances of the measured BPF are demonstrated, including low insertion loss (<1.9 dB), good return loss (>20 dB), a 16–49% fractional bandwidth tuning range and a wide upper stopband with better than 35 dB rejection. The proposed ideas are verified by the measured results. © 2015 Wiley Periodicals, Inc. Microwave Opt Technol Lett 57:1111–1113, 2015
Multilayer multipermittivity ring dielectric resonator antenna filter
Authors: Jyani Ashok K. , Awasthi Seema , Biswas Animesh
Published: March 2015

This article presents a multilayer multipermittivity (MLMP) ring dielectric resonator (DR) which is simultaneously used as a filter and an antenna, hence called dielectric resonator antenna filter. Multiple stacked layer of different permittivity along with the ring feature of DR gives a wideband response for antenna part with improved spurious response. In the presented MLMP ring DR, HEE11 and TE01δ modes are used for antenna and filter element, respectively. As HEE11 and TE01δ are orthogonal in nature that gives an independent control over filter and antenna characteristics. Measurement result reports an impedance bandwidth of 38.06% for dielectric resonator antenna (DRA) covering frequency range from 5 to 7.35 GHz for DRA and 3‐dB bandwidth is 211 MHz covering frequency range from 5.82 to 6.03 GHz for dielectric resonator filter (DRF). The measured resonance frequency is 5.38 and 5.93 GHz of DRA and DRF, respectively. © 2015 Wiley Periodicals, Inc. Microwave Opt Technol Lett 57:1147–1152, 2015
A CMOSUWBOOK pulse generator with multiple pulses per bit
Authors: Bae Yoon Jae , Cho Choon Sik , Kim Young‐Jin
Published: March 2015

This letter demonstrates a CMOS impulse radio ultrawideband (IR‐UWB) on–off keying (OOK) generator with multipulses per bit generation. The proposed IR‐UWB OOK generator is implemented in 0.11 μm CMOS process where 1.33 mm2 proto‐type accomplishes pulse train of 250 Mbps for one bit duration while consuming 10 mW from 1 V supply voltage. This pulse generator complies with the FCC spectral mask for indoor UWB systems. It consists of impulse generator, LC oscillator, delay cell, and pulse shaping filter with which pulses are repeated in every 4 ns irrespectively of input data rates. The output pulse centering at 3.8 GHz provides multiple pulses per bit with 210 mVpp and 40 pJ/pulse energy consumption. Bandwidth based on −10 dB attenuation from the main beam is measured to be 0.65 GHz. © 2015 Wiley Periodicals, Inc. Microwave Opt Technol Lett 57:1177–1180, 2015
Polymer MMI coupler for millimeter wave demultiplexing
Authors: Herschel Reinhold , Bierwirth Christoph , Schäffer Christian G.
Published: March 2015

A multimode interference (MMI) millimeter wave demultiplexer is presented. It is based on image ridge waveguides made from standard polymers. CNC milling and 3D printing are demonstrated to form the device. At 80 GHz, an extinction of almost 60 dB is obtained for a first‐order MMI‐based polystyrene device. © 2015 Wiley Periodicals, Inc. Microwave Opt Technol Lett 57:1184–1187, 2015
Millimeter‐wave wide beamwidth aperture–coupled antenna designed by mode synthesis
Authors: Lee Chang‐Hyun , Lee Jeong‐Hae
Published: March 2015

In this letter, a wide beamwidth aperture–coupled antenna is designed by mode synthesis at the millimeter‐wave frequency. To obtain the wide beamwidth, a TM010 mode and a zeroth‐order resonance mode of a metamaterial antenna are combined. A theoretical equation of synthesized radiation pattern is derived to find the conditions to obtain the widest E‐plane half power beamwidth (HPBW). By utilizing the equation, the optimal phase difference and injected power ratio to two antennas are found. The results are verified by a derived equivalent circuit and a full wave simulator. In addition, an aperture‐coupled feed that has an advantage to minimize the interference between a feed and an antenna has been used. Finally, the antenna with wide beamwidth is designed and fabricated at 35 GHz. The radiation efficiency and E‐plane HPBW of the designed antenna are simulated as 86.7% and 138°, respectively, which roughly agree with the measured results. © 2015 Wiley Periodicals, Inc. Microwave Opt Technol Lett 57:1255–1259, 2015
Leaky‐wave antenna design using quarter‐mode substrate‐integrated waveguide
Authors: Lee Dongju , Lim Sungjoon
Published: March 2015

A leaky‐wave antenna (LWA) is designed using quarter‐mode substrate‐integrated waveguide (QMSIW). The LWA unit cell is miniaturized because the QMSIW size is quarter of SIW cavity. A traveling wave leaks away from open edges of the QMSIW. Its performance is verified with full‐wave simulation and measurements. The main beam direction varies from 0 to 28° when frequency varies from 12.5 to 15.4 GHz. © 2015 Wiley Periodicals, Inc. Microwave Opt Technol Lett 57:1234–1236, 2015
Comparison of reconstruction accuracy of sparse recovery algorithms for gapped RCS data
Authors: Bae Ji‐Hoon , Park Sang‐Hong , Kang Byung‐Soo , Kim Kyung‐Tae , Yang Eunjung
Published: March 2015

This study evaluates and compares the reconstruction accuracy of sparse recovery algorithms (SRAs) when we reconstruct a two‐dimensional (2D) inverse synthetic aperture radar (ISAR) image from a gapped radar‐cross‐section (RCS) dataset. To analyze the influence of the gap on the reconstruction accuracy, we adopted a relative error (RE) in a 2D image domain, and evaluated the reconstruction accuracy of each method by calculating each RE value against the rate of missing data in the gap. The accuracy of the basis pursuit denoising method was better than that of other methods considered in this study, especially when we reconstructed the ISAR image from the gapped RCS dataset when signal‐to‐noise ratio was low. Consequently, the relaxed constraint rather than the strictly equality constraint for the SRA is more adequate for SRA applied to radar imaging. © 2015 Wiley Periodicals, Inc. Microwave Opt Technol Lett 57:1249–1255, 2015
Analysis and design of a branch‐line balun with high‐isolation wideband characteristics
Authors: Kim Phirun , Chaudhary Girdhari , Jeong Yongchae
Published: March 2015

This article presents a design of wideband balun with high isolation using a branch‐line structure. Theoretical analysis of the proposed balun shows that the reflection coefficient characteristics with two transmission poles can be obtained by controlling the characteristic impedances of transmission lines (Zt, Z1, and Z2). The high isolation can be obtained by adding a shunt coupled‐line short stub and resistor (R) between the output ports. The proposed balun was designed at the center frequency (f0) of 2.6 GHz for a current‐mode class‐S amplifier application. The measured results were in good agreement with the simulations, showing that power division ratios were 3.09 dB and 3.14 dB, whereas the return loss was 21.39 dB at the f0and higher than 20 dB over a bandwidth of 0.98 GHz (1.98–2.96 GHz). The isolation between output ports was higher than 18 dB for the bandwidth of 0.75 GHz (2.21–2.96 GHz). The measured phase difference between the output ports was 180° ± 9° over a frequency range of 2.2–2.98 GHz. © 2015 Wiley Periodicals, Inc. Microwave Opt Technol Lett 57:1228–1234, 2015
Combined‐type triple‐wideband LTE tablet computer antenna
Authors: Wong Kin‐Lu , Tsai Chih‐Yu
Published: March 2015

A combined‐type triple‐wideband tablet computer antenna covering the long term evolution (LTE) operation in the 698–960 MHz (low band), 1710–2690 MHz (middle band), and 3400–3800 MHz (high band) is presented. The antenna is formed by an inverted‐F antenna (IFA) covering the LTE low band and a coupled‐fed loop antenna covering the LTE middle and high bands. The IFA (low‐band antenna) and coupled‐fed loop antenna (middle/high‐band antenna) are easily combined into a compact structure to occupy a small ground clearance of 10 × 30 mm2 and a thin thickness of 3 mm. Details of the antenna structure are described in this study. Working principle of the antenna to achieve the LTE triple‐wideband operation through combining the low‐band antenna and the middle/high‐band antenna is addressed. Experimental results of the fabricated antenna are also presented and discussed. © 2015 Wiley Periodicals, Inc. Microwave Opt Technol Lett 57:1262–1267, 2015
Triband filter with high design flexibility and wide stopband using DGS and shorted stub‐loaded resonator
Authors: Peng Biao , Li Shufang , Zhang Bo , Wang Shuai
Published: March 2015

In this article, a novel triband bandpass filter with high design flexibility and wide stopband is designed by combining a shorted stub‐loaded resonator and two cross‐coupled DGS (defected ground structure) resonators [two RF (radio frequency) passages] with the same feeding structure. The three passbands can be flexibly designed not only because there is no cross‐coupling between the two passages but also because the harmonic passband can be easily eliminated just by embedding the feeding structure with open‐circuited stubs, while the performance of the three passbands remains the same. What's more, there are two transmission zeros beside each passband. A prototype filter with three passbands centered at 1.57, 3.45, and 5.28 GHz is designed and fabricated, and it behaves a wide upper stopband to about 9.6 GHz with rejection better than 20 dB. © 2015 Wiley Periodicals, Inc. Microwave Opt Technol Lett 57:1226–1228, 2015
On modeling of discrete propagation of localized damage in cohesive‐frictional materials
Authors: Haghighat E. , Pietruszczak S.
Published: March 2015

In this paper, the problem of propagation of localized deformation associated with formation of macrocracks/shear bands is studied in both tensile and compressive regimes. The main focus here is on enhancement of the constitutive law with embedded discontinuity to provide a discrete representation of the localization phenomenon. This has been accomplished by revising the formulation and coupling it with the level‐set method for tracing the propagation path. Extensive numerical studies are conducted involving various fracture modes, ranging from brittle to frictional, and the results are compared with the experimental data as well as those obtained using XFEM methodology. Copyright © 2015 John Wiley & Sons, Ltd.
A guideline for the management of bladder dysfunction in Parkinson's disease and other gait disorders
Authors: Sakakibara Ryuji , Panicker Jalesh , Finazzi‐Agro Enrico , Iacovelli Valerio , Bruschini Homero ,   The Parkinson's Disease Subcomittee, The Neurourology Promotion Committee in The International Continence Society
Published: March 2015

Parkinson's disease (PD) is a common neurodegenerative disorder, and lower urinary tract (LUT) dysfunction is one of the most common autonomic disorders with an estimated incidence rate of 27–80%. Studies have shown that bladder dysfunction significantly influences quality‐of‐life (QOL) measures, early institutionalisation, and health economics. We review the pathophysiology of bladder dysfunction in PD, lower urinary tract symptoms (LUTS), objective assessment, and treatment options. In patients with PD, disruption of the dopamine D1‐GABAergic direct pathway may lead to LUTS. Overactive bladder (OAB) is the most common LUT symptom in PD patients, and an objective assessment using urodynamics commonly shows detrusor overactivity (DO) in these patients. The post‐void residual (PVR) volume is minimal in PD, which differs significantly from multiple system atrophy (MSA) patients who have a more progressive disease that leads to urinary retention. However, subclinical detrusor weakness during voiding may also occur in PD. Regarding bladder management, there are no large, double‐blind, prospective studies in this area. It is well recognised that dopaminergic drugs can improve or worsen LUTS in PD patients. Therefore, an add‐on therapy with anticholinergics is required. Beta‐3 adrenergic agonists are a potential treatment option because there are little to no central cognitive events. Newer interventions, such as deep brain stimulation (DBS), are expected to improve bladder dysfunction in PD. Botulinum toxin injections can be used to treat intractable urinary incontinence in PD. Transurethral resection of the prostate gland (TURP) for comorbid BPH in PD is now recognised to be not contraindicated if MSA is excluded. Collaboration of urologists with neurologists is highly recommended to maximise a patients' bladder‐associated QOL. Neurourol. Urodynam. 35:551–563, 2016. © 2015 Wiley Periodicals, Inc.
Sorcery and the Moral Economy of Agency: An Ethnographic Account
Authors: Taylor John P.
Published: March 2015

An ethnographic account of sorcery accusation, violence, and subsequent community discussion provides a basis to explore the ‘moral economy of agency’ that shapes expressions and interpretations of personhood in Vanuatu. Mediated historically by transforming social, political, and economic circumstances, agency is demonstrated to be patterned according to culturally specific ontological and moral schemes. Key local categories of embodied personhood – including man ples (man place), man wan (man one), and jelus (jealousy) – are examined to elucidate two relationally entwined analytic categories, referred to as ‘distributive’ and ‘possessive’ agency. Such categories, it is argued, fundamentally shape expressions and interpretations of moral being and doing, including by providing a basis for identifying morally abject expressions of personhood. Taking seriously the important role of spiritual agency within such moral economies, this paper provides new ethnographically grounded insights into the ways in which communities and individuals negotiate moral being within transforming contexts of economic and sacred power.
‘I am Still a Young Girl if I Want’: Relational Personhood and Individual Autonomy in the Trobriand Islands
Authors: Lepani Katherine
Published: March 2015

In the Trobriand Islands of Papua New Guinea, sexuality is valued as a positive expression of relational personhood, registering the efficacy of consensual and pleasurable practice in producing and maintaining social relations. The power of sexuality to demonstrate individual and collective capacity and potential holds particular salience for unmarried young people. This paper draws on my ethnographic research on culture and HIV in the Trobriands to address perduring questions about the locus of individual autonomy in Melanesian sociality, where relational personhood shapes identity and modes of exchange in the moral economy. I focus on the gendered agency of youth sexuality, including the use of kwaiwaga, or love magic, in exercising and controlling desire. The narrative identities of two young women provide the lens through which questions of agency are explored, revealing how the autonomous mind, nanola, is central to understanding the embodiment of social relations, how the power of love magic transfers agency from one individual to another, and how individual assertions and acts are ultimately expressions of situated relationality.
Gender in a Land‐Based Theology
Authors: Tomlinson Matt
Published: March 2015

InFijian Methodist discourse, thevanua(land and people) is often characterised as the foundation of the traditional order and all it entails. Indigenous theologians attend to thevanuain novel ways, especially as it is paired in a half‐complementary, half‐oppositional way toChristianity. The question of whether thevanuamight be understood in gendered terms highlights a gap between theoretically universal values and practically patriarchal norms. In this article,Idiscuss several innovative thinkers on this subject: (1) women in the ‘Weavers’ theological collective; (2) the Methodist theologian and former churchPresidentIlaitiaSevatiTuwere; and (3) a femaleMethodist minister,Tima, whomIinterviewed in 2009.Ifocus especially onTuwere's description of the ‘feminine face’ of thevanuaandTima's continual and wrenching conflict with the church's male‐dominated hierarchy. WhereasTuwere uses a quasi‐feministChristian theology to reconcileChristianity and thevanuain terms of gender,Tima implies that her experiences of conflict with older men demonstrate howChristianity and thevanuamight not be fully reconcilable.
‘Break Down These Walls’: Space, Relations, and Hierarchy inFijian EvangelicalChristianity
Authors: Morgain Rachel
Published: March 2015

Patterns of sociality inFijian evangelicalChristianity differ from the mainlineFijianMethodist church in being notably less integrated with relations ofvanuaand chiefly hierarchy, leading scholars to speculate as to whether such traditions are more individualised. Analysing teachings, hymns, worship styles and spatial arrangements within a prominentFijianPentecostal ministry, I explore how sociality is produced through the interaction of spatial, conceptual, and embodied processes. Competing dynamics of hierarchy and equality, connections and boundaries, are mobilised within an overall framework that emphasises individual moral authority and personal relationship withGod. Through this analysis, in conversation with previous studies, this paper argues for a critical examination of schemes of ‘egalitarian individualism’ and ‘hierarchical holism’, which, through the influence ofLouisDumont in particular, have been prominent in studies ofChristianity and sociality inOceania.
Second malignant neoplasms among children, adolescents and young adults with Wilms tumor
Authors: Lee Jean S. , Padilla Benjamin , DuBois Steven G. , Oates Aris , Boscardin John , Goldsby Robert E.
Published: March 2015

Background

The goal of this study was to describe the incidence, characteristics, and outcomes of secondary malignant neoplasms (SMN) in survivors of Wilms tumor.

Procedures

Patients who were 0–20 years of age at time of primary diagnosis with Wilms tumor and reported to the Surveillance, Epidemiology, and End Results [SEER] program between 1973 and 2011 were eligible for inclusion in the cohort. We used competing risks methods to estimate the cumulative incidence of SMNs and assess contributing factors for developing SMN. We estimated standardized incidence ratios (SIR), absolute excess risk and overall survival after SMN using standard methods.

Results

Within the SEER database, 2,851 patients were diagnosed with Wilms tumor as their first malignancy. Of these, 34 patients were reported to have a SMN. Cumulative incidence of for a secondary malignancy was 0.6% (95% confidence interval [95% CI] 0.3–1.0%) at 10 years, 1.6% (95% CI 1.0–2.3%) at 20 years, and 3.8% (95% CI 2.4–5.9%) at 30 years. Median time from primary diagnosis to SMN diagnosis was 12.5 years. SIR for SMN for survivors of Wilms tumor was 3.4 (95% CI 2.2–4.9) with an absolute excess risk of 7.6 per 10,000 persons per year. Exposure to radiation did not significantly increase risk for development of second malignancy. Overall survival for patients with SMN was 64.5% at 5 years.

Conclusion

Survivors of Wilms tumor are at an increased risk of SMN compared to the general population, but the added risk is relatively small compared to other pediatric cancers. Pediatr Blood Cancer 2015;62:1259–1264. © 2015 Wiley Periodicals, Inc.
Health related quality of life and perception of stigmatisation in adolescents living with sickle cell disease in Nigeria: A cross sectional study
Authors: Adeyemo Titilope A. , Ojewunmi Oyesola O. , Diaku‐Akinwumi Ijeoma N. , Ayinde Oluwaseyi C. , Akanmu Alani S.
Published: March 2015

Background

Sickle cell disease impacts the physical, emotional and psychological aspects of life of the affected persons, often times exposing them to disease associated stigma from the society and alters the health related quality of life (HRQoL). This study compared the HRQoL of adolescents with sickle cell disease with their healthy peers, identified socio‐demographic and clinical factors impacting HRQoL, and determined the extent and effects of SCD related stigma on quality of life.

Procedure

We conducted a cross‐sectional survey among 160 adolescents, 80 with SCD and 80 adolescents without SCD. Socio‐demographic and clinical data were collected using a pre‐tested questionnaire. HRQoL was investigated using the Short Form (SF‐36v2) Health Survey. SCD perceived stigma was measured using an adaptation of a perceived stigma questionnaire.

Results

Adolescents with SCD have significantly worse HRQoL than their peers in all of the most important dimensions of HRQoL (physical functioning, physical roles limitation, emotional roles limitation, social functioning, bodily pain, vitality and general health perception) except mental health. Recent hospital admission and SCD related complication further lowered HRQoL scores. Over seventy percent of adolescents with SCD have moderate to high level of perception of stigmatisation. Hospitalisation, SCD complication, SCD stigma were inversely, and significantly associated with HRQoL.

Conclusions

Adolescents living with SCD in Nigeria have lower health related quality of life compared to their healthy peers. They also experience stigma that impacts their HRQoL. Complications of SCD and hospital admissions contribute significantly to this impairment. Pediatr Blood Cancer 2015;62:1245–1251. © 2015 Wiley Periodicals, Inc.
Donor–acceptor semiconducting polymers based on pyromellitic diimide
Authors: Kularatne Ruvini S. , Sista Prakash , Magurudeniya Harsha D. , Hao Jing , Nguyen Hien Q. , Biewer Michael C. , Stefan Mihaela C.
Published: March 2015

Three donor–acceptor copolymers P1, P2, and P3 with N,N′‐dodecylpyromellitic diimide as the electron‐acceptor unit with three diethynyl‐substituted donor monomers: 1,4‐diethynyl‐2,5‐bis(octyloxy)benzene, 2,7‐diethynyl‐9,9‐dioctyl‐9H‐fluorene, and 3,3′‐didodecyl‐5,5′‐diethynyl‐2,2′‐bithiophene have been synthesized by Sonogashira crosscoupling polymerization. The synthesized polymers showed deep highest occupied molecular orbital energy levels and larger band gaps (>2.5 eV). Polymers P1, P2, and P3 underwent fluorescence quenching with [6,6]‐phenyl‐C61‐butyric acid methyl ester (PCBM), indicating the intermolecular photo‐induced charge transfer between the donor polymers and the PCBM acceptor. © 2015 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2015, 53, 1617–1622
Pressure Dependence of the Reaction Propagation Rate of TATB at High Pressure
Authors: Foltz M. Frances
Published: March 2015

Druckabhängigkeit der Reaktionszonen‐Ausbreitungsgeschwindigkeit bei TATB unter hohem Druck

Die Reaktionszonen‐Ausbreitungsgeschwindigkeit (RPR) des unempfindlichen Hochleistungssprengstoffs 1,3,5‐Triamino‐2,4,6‐trinitrobenzol (TATB) wurde gemessen in einer Diamantstempelzelle im Druckbereich zwischen 3 GPa und 40 GPa. Unregelmäßigkeiten in der RPR wurden beobachtet in Abhängigkeit vom Druck bei 19 GPa, 30 GPa und 40 GPa (± GPa). Ansteigender Druck verursachte eine fortschreitende Farbänderung des TATB beim Umgebungsdruck von gelb nach rot, dann nach schwarz oberhalb 30 GPa. Gleichzeitig wurde ein irreversibles Auftreten von Einschlüssen bei hohem Druck beobachtet (scharf abgegrenzte polykristalline Zonen). Eine Phasenumwandlung analog der zwischen Graphit und Diamant unter Bildung einer 3‐d Netzwerk‐Wurtzitstruktur wird angenommen. Die vorliegenden Daten werden verglichen mit früher veröffentlichten druckabhängigen RPR‐Werten von Nitromethan.
Molecular Origin of the Influence of the Temperature on the Loss Factor of a Solid Propellant
Authors: Azoug Aurélie , Nevière Robert , Constantinescu Andrei
Published: March 2015

This study focuses on the viscoelastic behavior of an industrial hydroxyl‐terminated polybutadiene (HTPB) based solid propellant. The analysis of the loss factor as function of temperature enables the investigation of the molecular mechanisms participating in the nonlinear viscoelastic behavior. A design of experiments determines the influences of the filler fraction, of the NCO/OH ratio, of the plasticizer content, and of the presence or absence of filler‐binder bonding agents. For all the tested materials, the loss factor as function of temperature exhibits two distinct peaks when measured by Dynamic Mechanical Analysis. Exponentially modified Gaussian distributions are applied on each peak to characterize the behavior. While the first peak is commonly associated with the rubber‐glass transition of the material, the second peak has not been clearly associated with a molecular mechanism. This study shows that the second peak of the loss factor in HTPB‐based solid propellants originates from the flow of free polymer chains in the polymer network with a reptation mechanism. The sol polymer fraction controls the area of the second peak, whereas its temperature at the maximum corresponds to an activation temperature determined by the molar masses of the sol polymer. Finally, when the propellant is stretched, a decrease in area and an increase in the temperature of the peak show that the reptation of the sol polymer chains is constrained by the network.
Degradation mechanisms and lifetime of state‐of‐the‐art green laser diodes
Authors: Marioli M. , Meneghini M. , Rossi F. , Salviati G. , de Santi C. , Mura G. , Meneghesso G. , Zanoni E.
Published: March 2015

This paper presents a detailed analysis of the degradation kinetics and of the reliability of state‐of‐the‐art InGaN‐based green laser diodes (LDs), submitted to CW stress tests at different operating conditions. Results described in the following indicate that: (i) constant current stress induces an increase in threshold current (Ith), which is well correlated to a decrease in the sub‐threshold emission; (ii) the Ith increase has a power law dependence on stress time; (iii) the degradation rate is strongly dependent on the stress current level while it does not significantly depend on the optical field in the cavity; (iv) stress temperature acts as an accelerating factor for LDs degradation; the activation energy of the degradation process is equal to 258 meV; (v) pure thermal storage does not induce a significant degradation of device characteristics. Cathodoluminescence measurements were carried out to get more insight into the physical origin of the degradation process.
Systematic evaluation of label‐free and super‐SILAC quantification for proteome expression analysis
Authors: Tebbe Andreas , Klammer Martin , Sighart Stefanie , Schaab Christoph , Daub Henrik
Published: March 2015

Rationale

Advanced implementations of mass spectrometry (MS)‐based proteomics allow for comprehensive proteome expression profiling across many biological samples. The outcome of such studies critically depends on accurate and precise quantification, which has to be ensured for high‐coverage proteome analysis possible on fast and sensitive mass spectrometers such as quadrupole orbitrap instruments.

Methods

We conducted ultra‐high‐performance liquid chromatography (UHPLC)/MS experiments on a Q Exactive to systematically compare label‐free proteome quantification across six human cancer cell lines with quantification against a shared reference mix generated by stable isotope labeling with amino acids in cell culture (super‐SILAC).

Results

Single‐shot experiments identified on average about 5000 proteins in the label‐free compared to about 3500 in super‐SILAC experiments. Label‐free quantification was slightly less precise than super‐SILAC in replicate measurements, verifying previous results obtained for lower proteome coverage. Due to the higher number of quantified proteins, more significant differences were detected in label‐free cell line comparisons, whereas a higher percentage of quantified proteins was identified as differentially expressed in super‐SILAC experiments. Additional label‐free replicate analyses effectively compensated for lower precision of quantification. Finally, peptide fractionation by high pH reversed‐phase chromatography prior to LC/MS analysis further increased the robustness and precision of label‐free quantification in conjunction with higher proteome coverage.

Conclusions

Our results benchmark and highlight the utility of label‐free proteome quantification for applications such as target and biomarker discovery on state‐of‐the‐art UHPLC/MS workflows. Copyright © 2015 John Wiley & Sons, Ltd.
Application of chemometrics to resolve overlapping mass spectral peak clusters between trichloroethylene and its deuterated internal standard
Authors: Zhang Mengliang , Harrington Peter de B.
Published: March 2015

Rationale

Using one or two 2H‐atom‐labeled analogs as internal standards (ISs) may cause a 'cross‐contribution' problem (i.e., the overlap of ions from the IS and the analyte) especially for halogenated volatile organic compounds (VOCs). However, in this situation the overlapping peak clusters of the analyte and ISs can be resolved by multivariate chemometric methods such as classical least‐squares (CLS) and inverse least‐squares (ILS).

Methods

Trichloroethylene (TCE) and its internal standard, deuterated TCE (TCE‐d), as model compounds, were analyzed using portable gas chromatography/mass spectrometry. CLS and ILS were applied to resolve overlapping TCE and TCE‐d mass spectral signals and evaluated for the determination of TCE. CLS and ILS models were constructed and used to predict concentration ratios of TCE to TCE‐d. Calibration samples were prepared by adding TCE at different concentrations and TCE‐d at 300 ng mL–1 as an IS.

Results

The calibration curve was linear over a range of 10–1000 ng mL–1 with a coefficient of determination (R2) of 0.993. A validation data set collected 2 weeks later was used to further test the model robustness. Lower prediction errors and higher correlation coefficients were obtained from TCE/TCE‐d ratios predicted by the CLS model.

Conclusions

This paper describes the first application of CLS to deconvolute overlapping peaks between an analyte and its corresponding isotopic internal standard for quantification. The proposed method enables simple isotopic analogs of analytes (one H or C atom is isotopically labeled) to be used as internal standards for analytes with isotopic distributions. It has wide application because of the environmental impact and prevalence of halogenated VOCs, especially when analytes have isotopic distributions that overlap with an internal standard or when sophisticated isotopic analogs of the analytes with three or more 2H‐ or/and 13C‐atoms are prohibitively expensive or even impossible. Copyright © 2015 John Wiley & Sons, Ltd.
Population and individual foraging patterns of two hammerhead sharks using carbon and nitrogen stable isotopes
Authors: Loor‐Andrade P. , Galván‐Magaña F. , Elorriaga‐Verplancken F. R. , Polo‐Silva C. , Delgado‐Huertas A.
Published: March 2015

Rationale

Individual foraging behavior is an important variable of predators commonly studied at the population level. Some hammerhead shark species play a significant role in the marine ecosystem as top consumers. In this context, stable isotope analysis allows us to infer some ecological metrics and patterns that cannot usually be obtained using traditional methods.

Methods

We determined the isotopic composition (δ13C and δ15N values) of dorsal muscle and vertebrae of Sphyrna lewini and Sphyrna zygaena using a continuous‐flow system consisting of an elemental analyzer combined with a Delta Plus XL mass spectrometer. Foraging variability by sex and by individual was inferred from the isotopic values.

Results

There were no significant differences in the isotopic values of muscle samples between sexes, but there were differences between species. The trophic niche breadth of the two species was similar and overlap was low. A low niche overlap was observed between S. lewini individual vertebrae. We found differences in the δ15N values of S. zygaena vertebrae, with lower values in the first group of samples.

Conclusions

Despite these hammerhead shark species inhabiting the same area, there was low trophic niche overlap between species and individuals, due to different individual foraging strategies, according to the carbon and nitrogen isotopic profiles obtained. The use of tissues that retain lifetime isotopic information is useful to complement studies on trophic ecology. Copyright © 2015 John Wiley & Sons, Ltd.
Computation of lower bounds for the induced norm of LPV systems
Authors: Peni Tamas , Seiler Peter J.
Published: March 2015

Determining the induced
norm of a linear parameter‐varying (LPV) system is an integral part of many analysis and robust control design procedures. Most prior work has focused on efficiently computing upper bounds for the induced
norm. The conditions for upper bounds are typically based on scaled small‐gain theorems with dynamic multipliers or dissipation inequalities with parameter‐dependent Lyapunov functions. This paper presents a complementary algorithm to compute lower bounds for the induced
norm. The proposed approach computes a lower bound on the gain by restricting the parameter trajectory to be a periodic signal. This restriction enables the use of recent results for exact calculation of the
norm for a periodic linear time varying system. The proposed lower bound algorithm also returns a worst‐case parameter trajectory for the LPV system that can be further analyzed to provide insight into the system performance. Copyright © 2015 John Wiley & Sons, Ltd.
Bayesian regression discontinuity designs: incorporating clinical knowledge in the causal analysis of primary care data
Authors: Geneletti Sara , O'Keeffe Aidan G. , Sharples Linda D. , Richardson Sylvia , Baio Gianluca
Published: March 2015

The regression discontinuity (RD) design is a quasi‐experimental design that estimates the causal effects of a treatment by exploiting naturally occurring treatment rules. It can be applied in any context where a particular treatment or intervention is administered according to a pre‐specified rule linked to a continuous variable. Such thresholds are common in primary care drug prescription where the RD design can be used to estimate the causal effect of medication in the general population. Such results can then be contrasted to those obtained from randomised controlled trials (RCTs) and inform prescription policy and guidelines based on a more realistic and less expensive context. In this paper, we focus on statins, a class of cholesterol‐lowering drugs, however, the methodology can be applied to many other drugs provided these are prescribed in accordance to pre‐determined guidelines. Current guidelines in the UK state that statins should be prescribed to patients with 10‐year cardiovascular disease risk scores in excess of 20%. If we consider patients whose risk scores are close to the 20% risk score threshold, we find that there is an element of random variation in both the risk score itself and its measurement. We can therefore consider the threshold as a randomising device that assigns statin prescription to individuals just above the threshold and withholds it from those just below. Thus, we are effectively replicating the conditions of an RCT in the area around the threshold, removing or at least mitigating confounding. We frame the RD design in the language of conditional independence, which clarifies the assumptions necessary to apply an RD design to data, and which makes the links with instrumental variables clear. We also have context‐specific knowledge about the expected sizes of the effects of statin prescription and are thus able to incorporate this into Bayesian models by formulating informative priors on our causal parameters. © 2015 The Authors.Statistics in MedicinePublished by John Wiley & Sons Ltd.
Two‐stage designs for cross‐over bioequivalence trials
Authors: Kieser Meinhard , Rauch Geraldine
Published: March 2015

The topic of applying two‐stage designs in the field of bioequivalence studies has recently gained attention in the literature and in regulatory guidelines. While there exists some methodological research on the application of group sequential designs in bioequivalence studies, implementation of adaptive approaches has focused up to now on superiority and non‐inferiority trials. Especially, no comparison of the features and performance characteristics of these designs has been performed, and therefore, the question of which design to employ in this setting remains open. In this paper, we discuss and compare ‘classical’ group sequential designs and three types of adaptive designs that offer the option of mid‐course sample size recalculation. A comprehensive simulation study demonstrates that group sequential designs can be identified, which show power characteristics that are similar to those of the adaptive designs but require a lower average sample size. The methods are illustrated with a real bioequivalence study example. Copyright © 2015 John Wiley & Sons, Ltd.
Effects of power reserve control on wind turbine structural loading
Authors: Fleming Paul A. , Aho Jacob , Buckspan Andrew , Ela Erik , Zhang Yingchen , Gevorgian Vahan , Scholbrock Andrew , Pao Lucy , Damiani Rick
Published: March 2015

As the penetration of wind energy in worldwide electrical utility grids increases, there is a growing interest in the provision of active power control (APC) services from wind turbines and power plants to aid in maintaining grid stability. Recent research has focused on the design of active power controllers for wind turbines that can provide a range of APC services including inertial, primary frequency and secondary frequency control. An important consideration for implementing these controllers in practice is assessing their impact on the lifetime of wind turbine components.

In this paper, the impact on the structural loads of a wind turbine providing a power reserve is explored by performing a load suite analysis for several torque‐based control strategies. Power reserve is required for providing those APC services that require the ability of the wind turbine to supply an increase in power. To study this, we performed a load suite on a simulated model of a research turbine located at the National Wind Technology Center at the National Renewable Energy Laboratory. Analysis of the results explores the effect of the different reserve strategies on turbine loading. In addition, field‐test data from the turbine itself are presented to augment and support the findings from the simulation study results. Results indicate that all power‐reserve strategies tend to decrease extreme loads and increase pitch actuation. Fatigue loads tend to be reduced in faster winds and increased in slower winds, but are dependent on reserve‐controller design. Copyright © 2015 John Wiley & Sons, Ltd.
Relationship‐scale conservation
Authors: Brooks Jeffrey J. , Dvorak Robert G. , Spindler Mike , Miller Susanne
Published: March 2015

Conservation can occur anywhere regardless of scale, political jurisdiction, or landownership. We present a framework to help managers at protected areas practice conservation at the scale of relationships. We focus on relationships between stakeholders and protected areas and between managers and other stakeholders. We provide a synthesis of key natural resources literature and present a case example to support our premise and recommendations. The purpose is 4‐fold: 1) discuss challenges and threats to conservation and protected areas; 2) outline a relationship‐scale approach to address conservation threats; 3) describe the tools and techniques that can be used to implement this approach; and 4) present a case example from rural Alaska, USA, to illustrate relationship‐scale conservation. Our case example illustrates how aspects of this approach to conservation were applied to address a wildlife population decline. Tools needed to implement relationship‐scale conservation include 1) collecting and documenting narratives of place; 2) measuring and monitoring trust and commitment; and 3) identifying and mitigating threats. We recommend that planners and managers, working with their research partners, redefine and refocus their goals and objectives to include these practices. Doing so will enable them to gain substantial applied knowledge about their stakeholders and foster and maintain place relationships as desired outcomes of conservation. The ultimate outcome is a better prognosis for long‐term global survival of protected areas and biodiversity. Published 2014. This article is a U.S. Government work and is in the public domain in the USA.
Diffusion of Childbearing Within Cohabitation
Authors: Vitali Agnese , Aassve Arnstein , Lappegård Trude
Published: March 2015

The article analyzes the diffusion of childbearing within cohabitation in Norway, using municipality data over a 24-year period (1988–2011). Research has found substantial spatial heterogeneity in this phenomenon but also substantial spatial correlation, and the prevalence of childbearing within cohabitation has increased significantly over time. We consider several theoretical perspectives and implement a spatial panel model that allows accounting for autocorrelation not only on the dependent variable but also on key explanatory variables, and hence identifies the key determinants of diffusion of childbearing within cohabitation across space and over time. We find only partial support for the second demographic transition as a theory able to explain the diffusion of childbearing within cohabitation. Our results show that at least in the first phase of the diffusion (1988–1997), economic difficulties as measured by increased unemployment among men contributed to the diffusion of childbearing within cohabitation. However, the most important driver for childbearing within cohabitation is expansion in education for women.