bluuebunny/crossref_metadata_2025 huggingface dataset:
Loop‐loaded monopole antenna with miniaturization and dual‐band characteristics
Authors: Wu Wei‐Jun , Yin Ying‐Zeng , Zhang Zhi‐Ya , Zuo Shao‐Li , Xie Jiao‐Jiao
Published: March 2012

A novel miniaturized dual‐band monopole antenna loaded with two types of loops is presented. The split loop is loaded at the center of the monopole for dual‐band operation and the rectangular loop loaded at the top is for miniaturization. The novel miniaturization technique is used as a self resonant topology. The monopole below its resonant frequency is known to possess a capacitive reactance and the loop below its resonant frequency has an inductive reactance. So an inductive loop is used to match a below‐resonant monopole for miniaturization. As an example of this principle, a miniaturized dual‐band antenna prototype for WLAN applications is designed, fabricated, and tested. Measured results show that the antenna offers higher gains and better efficiencies than the unloaded monopole. The radiation patterns are seen to be unaffected by the presence of the top loaded loop. © 2012 Wiley Periodicals, Inc. Microwave Opt Technol Lett 54:1236–1239, 2012; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.26784
OpenMP parallelized MOD solution of the time‐domain EFIE accelerated by the ACA algorithm
Authors: Shi Yan , Jin Jian‐Ming
Published: March 2012

A parallelized marching‐on‐in‐degree (MOD) method accelerated by the adaptive cross approximation (ACA) algorithm is developed to solve the time‐domain electric‐field integral equation (TDEFIE) for the analysis of transient electromagentic scattering from a three‐dimensional conducting object of arbitrary shape. By using the entire‐domain temporal basis functions to expand the temporal variable of the TDEFIE and applying the Galerkin temporal testing procedure, the TDEFIE‐MOD algorithm overcomes the late‐time instability that often occurs in the time‐domain solutions. To exploit the rank‐deficient nature of the off‐diagonal subblocks in the TDEFIE‐MOD impedance matrix, the ACA algorithm is used to accelerate the matrix‐filling and matrix–vector multiplication operations. An OpenMP parallelization scheme is applied to further speed up the MOD‐ACA algorithm on a shared‐memory computer system. Numerical results are presented to illustrate the good computational performance of the proposed algorithm. © 2012 Wiley Periodicals, Inc. Microwave Opt Technol Lett 54:1206–1212, 2012; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.26785
Novel dual‐band bandstop filter with controllable stopband frequencies
Authors: Zhang Xiu Yin , Huang Xun , Zhang Hong‐Lin , Hu Bin‐Jie
Published: March 2012

This article presents a novel dual‐band bandstop filter (BSF) with controllable stopband frequencies and sharp skirt selectivity.The proposed filter consists of a main transmission line and stub‐loaded resonators coupled to the main line. The stub‐loaded resonator has the advantage that the even‐mode resonant frequencies can be flexibly controlled by changing the stub length without affecting the odd‐mode resonant frequencies. Using this configuration, the stopband frequencies can be easily tuned to desired values. Based on the proposed idea, a third‐order dual‐band BSF is implemented operating at 2.4 and 3.5 GHz. Comparisons of experimental and simulated results are presented and good performance is observed. © 2012 Wiley Periodicals, Inc. Microwave Opt Technol Lett 54:1203–1206, 2012; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.26786
Surface acoustic wave phononic crystal device fabricated by femtosecond laser ablation
Authors: Gertus Titas , Mikutis Mindaugas , Každailis Paulius , Rimeika Romualdas , Ciplys Daumantas , Smilgevičius Valerijus
Published: March 2012

Fabrication of surface acoustic wave (SAW) based phononic crystal (PC) device by femtosecond laser micromachining has been demonstrated. The thin‐film interdigital SAW transducers of 50 μm wavelength together with PC structure (1‐ and 2‐dimensional) of 25 μm period were fabricated on the YZ lithium niobate crystal surface by femtosecond pulse selective ablation of an aluminum layer. The device S parameter measurements revealed different influence of 1D and 2D PC structures on the SAW propagation. © 2012 Wiley Periodicals, Inc. Microwave Opt Technol Lett 54:1286–1287, 2012; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.26789
Ka/S dual‐band antenna for satellite communication
Authors: Xu Zhi , Liang Changhong
Published: March 2012

A novel space‐borne Ka/S dual‐band antenna is proposed in this article, in which the waveguide TE21‐mode automatic tracking is used for the Ka‐band.The two bands are common in structure but independent from each other electrically, thus the installation space specifications of the satellite platform can be met. The antenna design procedures as well as the measurement results are presented. © 2012 Wiley Periodicals, Inc. Microwave Opt Technol Lett 54:1246–1251, 2012; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.26791
Hexagonal ferrite‐piezoelectric composites for dual magnetic and electric field tunable 8–25 GHz microstripline resonators and phase shifters
Authors: Tatarenko A. S. , Murthy D. V. B. , Srinivasan G.
Published: March 2012

Microwave magnetoelectric (ME) effects over 8–25 GHz have been studied in bilayers of single crystal Y‐type hexagonal ferrite Ba2Zn2Fe12O22 and polycrystalline lead zirconate titanate (PZT) or single crystal lead magnesium niobate–lead titanate (PMN–PT). The bilayers are made by epoxy bonding or eutecting bonding the ferrite and piezoelectric. The strength of ME interactions A has been measured from data on electric field E tuning of magnetic modes in the ferrite. The electric field produces a mechanical deformation in the piezoelectric and results in a shift in the ferromagnetic resonance. Bilayers of ferrite/PMN–PT have A = 10 MHz cm/kOe and is an order of magnitude higher than for ferrite‐PZT. The ferrite/PMN–PT resonators could be tuned by 120 MHz with E = 12 kV/cm. Data on differential phase shift versus E indicate a differential phase shift of 50° for E = 12 kV/cm, a linear variation in the phase shift with E and an insertion loss of 4–8 dB. The bilayers are of interest for 8–25 GHz dual E‐ and H‐tunable ferrite resonators and phase shifters. © 2012 Wiley Periodicals, Inc. Microwave Opt Technol Lett 54:1215–1218, 2012; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.26793
Calibration methodology for a 3D radiation pattern set‐up of probe‐fed millimeter‐wave antennas
Authors: Titz Diane , Kyrö Mikko , Ferrero Fabien , Ranvier Sylvain , Luxey Cyril , Brachat Patrice , Jacquemod Gilles , Vainikainen Pertti
Published: March 2012

In this article, we present a radiation pattern measurement setup for probe‐fed millimeter‐wave antennas and the associated calibration procedure. Compared with other existing facilities, our setup has one major innovation: it is composed of two rotating arms allowing measuring the radiated field of a probe‐fed antenna over the quasi‐3D sphere. The calibration challenges and issues encountered at 60 GHz are thoroughly described. We especially detail a specific calibration procedure to improve the accuracy of the measurements. To illustrate our methodology, the 3D radiation pattern measurement of a novel monopole‐type antenna etched over a glass substrate is presented. Experimental results versus simulation results are compared. © 2012 Wiley Periodicals, Inc. Microwave Opt Technol Lett 54:1183–1189, 2012; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.26795
A triple‐band WLAN/WiMAX printed monopole antenna for MIMO applications
Authors: Foudazi Ali , Mallahzadeh Alireza , Nezhad Sajad Mohammad Ali
Published: March 2012

A triple‐band multi‐input multi‐output (MIMO) antenna is presented.The proposed antenna consists of a C‐shaped monopole antenna that provides dual‐band resonant antenna. By protruding an L‐shaped parasitic strip on the ground plane, a third band as well as enhancement of the isolation between two ports in MIMO array is achieved. The proposed antenna can cover 2.1–2.6, 3.3–4, and 5.4–6 GHz, which are allocated for WLAN and WiMAX applications. The proposed triple‐band antenna structure is used in different two‐element MIMO arrays. Simulation results show that the S11, S12, and S22 of the MIMO arrays are independent of the position of the two‐element. The results show good S‐parameters, high peak gain and radiation efficiency, and stable radiation patterns among the triple‐band coverage. © 2012 Wiley Periodicals, Inc. Microwave Opt Technol Lett 54:1321–1325, 2012; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.26799
Two‐channel fiber microcavity strain sensor based on fiber loop ring‐down spectroscopy technology
Authors: Jiabin Shang , Weigang Zhang , Shilei Wei , Hao Zhang
Published: March 2012

In this article, a two‐channel fiber microcavity strain sensor based on fiber loop ring‐down spectroscopy technology is proposed and implemented. This fiber loop ring‐down strain sensor uses time division multiplexing technique, which involves two fiber loops. These two fiber‐loop resonators share a same pulsed laser source and a same photodetector. The microcavity is directly inscribed in a segment of 1060 nm single mode fiber through high‐frequency CO2 laser pulses illumination. As a sensor unit, the two fiber microcavities accessible to the fiber‐loop resonators are pasted onto the upper and lower surface of a cantilever beam to realize the strain sensing by measuring the ring‐down time of the pulse laser. © 2012 Wiley Periodicals, Inc. Microwave Opt Technol Lett 54:1305–1309, 2012; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.26800
High performance WLAN balun using integrated passive technology on SI‐GaAs substrate
Authors: Wang Cong , Kim Nam‐Young
Published: March 2012

An integrated passive device (IPD) technology has been developed in order to achieve lower cost, further miniaturization, and higher performance in microwave devices applied to the front‐end modules of wireless communication system.This article describes a compact wireless local area network (WLAN) balun suitable for wireless system application using IPD technology based on an SI‐GaAs substrate. It shows very good RF performances in spite of its small chip size and low cost, compared to those found in recent literature. A small outline transistor packaging technology with a three‐dimensional electromagnetic simulation is reported. The fabricated WLAN balun has an insertion loss of < −0.25 dB and a return loss of > −25 dB. The phase imbalance was measured to be less than 3° and the amplitude imbalance is less than 0.5 dB; its dimensions are 800 μm × 700 μm × 200 μm. This compact WLAN balun can be used for a variety of applications in the microwave field. © 2012 Wiley Periodicals, Inc. Microwave Opt Technol Lett 54:1301–1305, 2012; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.26801
Alternating‐direction explicit algorithms for crank–nicolson‐based FDTD methods
Authors: Fu Ping , Chen Ru‐Shan
Published: March 2012

This article proposes a new unconditionally stable explicit finite‐difference time‐domain (FDTD) scheme for 3D Maxwell equation.The proposed scheme is based on alternating‐direction explicit method and Crank–Nicolson (CN)‐based FDTD method, and we present two versions of the proposed method. Numerical stability and dispersion analysis of the new algorithm were also presented. The results by the proposed method are compared with the results by the conventional FDTD method, alternating‐direction implicit method, and CN‐based FDTD method. As a result, it is confirmed that the proposed method is unconditionally stable and the efficiency is superior to the conventional method if the minimum cell size in the computational domains is required to be much smaller than the wavelength. © 2012 Wiley Periodicals, Inc. Microwave Opt Technol Lett 54:1269–1273, 2012; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.26802
Broadband UHF RFID tag antenna with a rectangular‐loop feed and additional patches
Authors: Tang Zhi‐jun , Zhan Jie , Xi Zai‐fang , He Yi‐gang
Published: March 2012

A novel tag antenna with a rectangular‐loop feed, a bent meandered strip and additional patches is designed and analyzed in ultra high frequency (UHF) radio frequency identification (RFID) bands to provide broadband, high gain, and size‐reduction performance simultaneously. It is designed to operate at UHF RFID bandwidths, with resonant frequencies of 842, 868, and 915 MHz, respectively. The dimension of the antenna with resonant frequencies of 915 MHz is around 78 × 23 mm2, which shows near linear phase characteristics. Simulated and measured results show the proposed antenna can obtain 100 MHz bandwidth under the condition of voltage standing wave ration less than 2 and 1.6 dBi gain for worldwide UHF RFID bands. In addition, the antenna provides a good radiation pattern. © 2012 Wiley Periodicals, Inc. Microwave Opt Technol Lett 54:1234–1236, 2012; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.26804
Structure elucidation and NMR assignments of an unusual triterpene saponin derivative from Ilex kudincha
Authors: Zuo Wenjian , Wang Qinghu , Li Wen , Sha Yi , Li Xian , Wang Jinhui
Published: March 2012

One unusual triterpenoid derivative, ilekudinchoside E (1), was isolated from the leaves of Ilex kudincha. The structure was established by various spectroscopic techniques, including one‐ and two‐dimensional NMR, HRTOFMS and CD spectra. Copyright © 2012 John Wiley & Sons, Ltd.
Monitoring in situ Electrochemical Crosslinking in Nanostructured Precursor Polymer Films by EC‐SPR Spectroscopy
Authors: Jiang Guoqian , Huang Chengyu , Baba Akira , Advincula Rigoberto
Published: March 2012

The optical/electrochemical and crosslinking properties of polycarbazole LbL films is studied using EC‐SPR spectroscopy. The in situ electrochemical crosslinking and doping/de‐doping properties are monitored for several different layered film structures. P4VPCBZ and PCEMMA are used as precursor polyelectrolytes, PAA and PDADMAC as non‐crosslinkable polyelectrolytes, which are effective barrier layers for electron transfer. The changes in reflectivity and charge during CV illustrates that quantitative control of electrochemical crosslinking and doping/de‐doping can be achieved by varying the composition of the precursor and counter‐polyelectrolyte layers. The method may provide new opportunities for basic studies of model conjugated polymer systems and for electrooptic device applications.

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Urinary Incontinence: Prevalence, Risk Factors, and Impact on Health Related Quality of Life in Saudi Women
Authors: Altaweel Waleed , Alharbi Mohannad
Published: March 2012

Aims

The aims of this study were to determine the prevalence, risk factors, and impact upon health related quality of life (HRQL) of urinary incontinence in Saudi women.

Methods

We performed a clinic‐based cross‐sectional survey. 6,600 women aged 20 years and older were selected. The bother of urinary incontinence symptoms was assessed using the Arabic version of the short form of Urogenital Distress Inventory (UDI‐6) questionnaire. We measured the impact of urinary incontinence on HRQL using the Incontinence Impact Questionnaire (IIQ‐7).

Results

The overall prevalence of urinary incontinence in our study was 29%. The prevalence of urinary incontinence according to its type was 50% stress urinary incontinence, 28% urgency urinary incontinence, and 22% mixed urinary incontinence. Older age, obesity, large baby birth weight, high parity, caesarean delivery, vaginal delivery, and diabetes were significant risk factors. Less than 10% of the women in this study reported a significant effect of urinary incontinence on their HRQL. In our study population, 9% sought medical care.

Conclusions

Twenty‐nine percent of the women in Riyadh suffered from urinary incontinence. Diabetes is the most significant factor. Urinary incontinence affects women's HRQL. Most of the women did not seek medical care. We consider our study as an important step to start the plans for early detection, and treating urinary incontinence in Saudi Arabia. Neurourol. Urodynam. 31:642–645, 2012. © 2012 Wiley Periodicals, Inc.
The psychology of LUTS: ICI‐RS 2011
Authors: Cortes E. , Sahai A. , Pontari M. , Kelleher C.
Published: March 2012

Introduction

There is undoubtedly a link between lower urinary tract and psychological symptoms. The association is likely to be multifactorial, but whether psychological symptoms are causal or coincidental remains unknown.

Methods

This paper is a result of a think tank session conducted at the ICI‐RS meeting 2011 in Bristol and a PubMed search on the subject of psychology and LUTS.

Results

Recent population studies have shown that LUTS are prevalent and that psychological morbidity is related to severity of LUTS. Evidence suggests that the psychological status of patients plays a significant role in their symptoms perception. Animal studies have shown the importance of programming and emotional stress on subsequent psychological problems. The link between early events in childhood and resulting LUTS in later life remains uncertain. The possibility that for some patients urinary symptoms could be part of a somatizing process requires further consideration. The possibility that patients' symptoms could be part of a somatization process needs further consideration. Neuroendocrine and neuroimaging studies suggest pathways that may link psychological and lower urinary tract functioning from early life, opening new avenues to better understand the treatment of both symptom groups.

Conclusion

Whilst psychological morbidity will result from any distressing chronic medical condition the possibility of causation, and or maintenance of LUTS through psychological causes requires further research. It is important to recognize that amongst our younger and older patients suffering with LUTS a significant psychological component exists. Failure to address this may lead to incomplete assessment and consequently inadequate treatment. Neurourol. Urodynam. 31:340–343, 2012. © 2012 Wiley Periodicals, Inc.
What determines whether a patient with LUTS seeks treatment?: ICI‐RS 2011
Authors: Apostolidis Apostolos , de Nunzio Cosimo , Tubaro Andrea
Published: March 2012

Aims

To review the known determinants of healthcare‐seeking behavior for LUTS and address unmet needs and future research priorities.

Methods

The PubMed literature was searched for currently known factors affecting treatment seeking for LUTS, OAB, and incontinence in men and women.

Results

Further to the great variation in rates for treatment seeking for LUTS in both men and women, several biomedical and psychosocial factors affecting HSB have been identified in studies to date. Symptom severity and bother, age, and impact on quality of life have consistently been identified as potent determinants of treatment seeking for LUTS. Race and ethnicity also play a role. Advice from others and the media, embarrassment, personal beliefs and attitudes towards healthcare use, and subjective well‐being are but a few of the psychosocial determinants which may impact on a patient's decision to seek medical advice for LUTS. Studying the role of reassurance versus medical treatment, referral patterns for LUTS in various populations, the role of comorbidities in HSB, cultural issues, bother‐associated parameters and psychosocial profiles in association with healthcare‐seeking, patients' expectations, HSB in relation to health economics, and development of questionnaires on HSB for patients and physicians should be amongst future research priorities.

Conclusions

Increasing research interest has helped identify several biomedical and psychosocial factors affecting HSB for LUTS. Qualitative research is needed as well as studies to address aspects of HSB, not only in subjects attending the available healthcare services, but even more in those patients who do not seek medical advice for their LUTS. Neurourol. Urodynam. 31:365–369, 2012. © 2012 Wiley Periodicals, Inc.
Defining female voiding dysfunction: ICI‐RS 2011
Authors: Robinson Dudley , Staskin David , Laterza Rosa M. , Koelbl Heinz
Published: March 2012

Whilst symptoms of Bladder Outlet Obstruction (BOO) and post micturition symptoms are more commonly reported in men a significant number of women may also complain of voiding dysfunction. However, despite the recent advances in the standardisation of terminology of lower urinary tract dysfunction there remains a lack of consensus regarding a precise diagnosis and definition of voiding abnormalities in women. In addition voiding symptoms may co‐exist with storage symptoms as well as those associated with urinary incontinence. Consequently many patients present with a spectrum of different urinary symptoms, related to both storage and voiding, which may be multifactorial in origin or be related to one another. The purpose of this paper is to review the current literature in order to accurately define and classify female voiding dysfunction including causes and aetiology. In addition to reviewing the investigation and management of those women with voiding dysfunction recommendations are proposed for management in clinical practice as well as suggestions for future research. Neurourol. Urodynam. 31:313–316, 2012. © 2012 Wiley Periodicals, Inc.
Does psychological stress affect LUT function in children?: ICI‐RS 2011
Authors: von Gontard Alexander
Published: March 2012

Aims

Psychological factors and LUTS are closely associated in children. 20–40% of children with nocturnal enuresis (NE) and 30–40% with daytime urinary incontinence (DUI) have a clinical psychiatric disorder, many more are distressed. The associations are complex and differ for each individual subtype of disorder, as both genetic and environmental factors can interact. The aim of this paper is to provide an overview and discuss possible causal associations.

Methods

Relevant studies are reviewed—preferably with population‐based, representative results.

Results

Four basic associations are possible. Psychological symptoms and disorders can (1) be a consequence of LUTS and NE/DUI; (2) They can be induced by them; (3) Both can be due to common, shared etiological factors; and (4) They can co‐occur by chance without causality.

Conclusions

Due to these complex associations, a descriptive approach is endorsed. Both the subtype of NE/DUI and possible psychological symptoms and disorders need to be identified—possible causal relationships can be analyzed in a second step. Screening for psychological symptoms with parental behavioral questionnaires in all settings is recommended, as well as counselling and treatment if indicated. Neurourol. Urodynam. 31:344–348, 2012. © 2012 Wiley Periodicals, Inc.
Will we ever use stem cells for the treatment of SUI?: ICI‐RS 2011
Authors: Goldman Howard B. , Sievert Karl‐Dietrich , Damaser Margot S.
Published: March 2012

Aims

To review the current state of research in the use of stem cells (SCs) for stress urinary incontinence (SUI) and assess the likelihood of this becoming a relevant treatment option.

Methods

The peer‐reviewed literature consisting of relevant clinical and animal studies on the topic of SUI was surveyed and reviewed.

Results

Animal studies have demonstrated the potential utility of SCs in promoting functional recovery of the urethra after simulated childbirth injury. Research in animals suggests similar urethral recovery after injection of bone marrow derived mesenchymal SC secretions as after injection of the SCs themselves. Therefore, whether the improvements result from the injection of the SCs themselves or from their secretion of specific proteins is unclear. Early clinical trials have demonstrated the feasibility and short‐term safety of injecting muscle‐derived SCs into the urethra to treat SUI.

Conclusions

Larger and longer‐term clinical trials are needed. Nonetheless, efficacious SC‐based therapy for the treatment of SUI is practical, achievable and should be available as a treatment modality in the near future. Neurourol. Urodynam. 31:386–389, 2012. © 2012 Wiley Periodicals, Inc.
Diffusion tensor quantification and cognitive correlates of the macrostructure and microstructure of the corpus callosum in typically developing and dyslexic children
Authors: Hasan Khader M. , Molfese David L. , Walimuni Indika S. , Stuebing Karla K. , Papanicolaou Andrew C. , Narayana Ponnada A. , Fletcher Jack M.
Published: March 2012

Noninvasive quantitative MRI methods, such as diffusion tensor imaging (DTI), can offer insights into the structure–function relationships in human developmental brain disorders. In this article, we quantified the macrostructural and microstructural attributes of the corpus callosum (CC) in children with dyslexia and in typically developing readers of comparable age and gender. Diffusion anisotropy, and mean, radial and axial diffusivities of cross‐sectional CC subregions were computed using a validated DTI methodology. The normalized posterior CC area was enlarged in children with dyslexia relative to that in typically developing children. Moreover, the callosal microstructural attributes, such as the mean diffusivity of the posterior middle sector of the CC, correlated significantly with measures of word reading and reading comprehension. Reading group differences in fractional anisotropy, mean diffusivity and radial diffusivity were observed in the posterior CC (CC5). This study demonstrates the utility of regional DTI measurements of the CC in understanding the neurobiology of reading disorders. Copyright © 2012 John Wiley & Sons, Ltd.
A new efficient convergence criterion for reducing computational expense in topology optimization: reducible design variable method
Authors: Kim Sun Yong , Kim Il Yong , Mechefske Chris K.
Published: March 2012

A new efficient convergence criterion, named the reducible design variable method (RDVM), is proposed to save computational expense in topology optimization. There are two types of computational costs: one is to calculate the governing equations, and the other is to update the design variables. In conventional topology optimization, the number of design variables is usually fixed during the optimization procedure. Thus, the computational expense linearly increases with respect to the iteration number. Some design variables, however, quickly converge and some other design variables slowly converge. The idea of the proposed method is to adaptively reduce the number of design variables on the basis of the history of each design variable during optimization. Using the RDVM, those design variables that quickly converge are not considered as design variables for the next iterations. This means that the number of design variables can be reduced to save the computational costs of updating design variables. Then, the iteration will repeat until the number of design variables becomes 0. In addition, the proposed method can lead to faster convergence of the optimization procedure, which indeed is a more significant time saving. It is also revealed that the RDVM gives identical optimal solutions as those by conventional methods. We confirmed the numerical efficiency and solution effectiveness of the RDVM with respect to two types of optimization: static linear elastic minimization, and linear vibration problems with the first eigenvalue as the objective function for maximization. Copyright © 2012 John Wiley & Sons, Ltd.
Grant making as advocacy: The emergence of social justice philanthropy
Authors: Suárez David F.
Published: March 2012

In recent decades the phrase “social justice philanthropy” has emerged to describe grant making for progressive social reform. This article investigates this new discourse based on a cross‐sectional analysis of foundations that actively support nonprofit social action. Smaller foundations, younger foundations, and public foundations are more likely to mention social justice or social change in their program descriptions than are other philanthropic institutions. Results indicate that foundations that set international grant making and rights activities as priorities are more likely to adopt this sensitive discourse than are foundations dedicated to other subjects; foundations with longer legacies of supporting reform also discuss social justice more frequently. This article begins to clarify which foundations provide legitimacy for social change nonprofits through their discourse and offers new insights into the role of foundations as policy actors. These findings suggest that the main advocates for a liberal policy voice within the philanthropic community may be smaller foundations and those incorporated as public foundations, a radical flank that pressures other foundations to expand their funding repertoire.
Service learning from the supply side: Community capacity to engage students
Authors: Littlepage Laura , Gazley Beth , Bennett Teresa A.
Published: March 2012

The rapid increase in the use of service learning raises important public policy questions about who is being served and whether partner agencies have the capacity to meet student demand for community‐based experiences. This article uses a large sample of nonprofit organizations and a comparative framework to examine the characteristics of partner agencies and the scope and nature of college student community involvement. Multivariate analysis tests these factors on a community agency's ability to engage more students, particularly service learners. The findings are generally optimistic about agency willingness to involve students, suggesting widespread community benefits from their involvement. While organizational size and capacity predict current student engagement, an agency's past experience with students and its perceptions of student benefits have the greatest impact on its willingness to take on future students.
Comparative safety of infliximab and etanercept on the risk of serious infections: does the association vary by patient characteristics?
Authors: Toh Sengwee , Li Lingling , Harrold Leslie R. , Bayliss Elizabeth A. , Curtis Jeffrey R. , Liu Liyan , Chen Lang , Grijalva Carlos G. , Herrinton Lisa J.
Published: March 2012

Purpose

Infliximab, a chimeric monoclonal anti‐TNFα antibody, has been found to increase the risk of serious infections compared with the TNF receptor fusion protein etanercept in some studies. It is unclear whether the risk varies by patient characteristics. We conducted a study to address this question.

Methods

We identified members of Kaiser Permanente Northern California who initiated infliximab (n = 793) or etanercept (n = 2692) in 1997–2007. Using a Cox model, we estimated the propensity‐score‐adjusted hazard ratio (HR) and 95% confidence interval (CI) of serious infections requiring hospitalization or opportunistic infections comparing infliximab initiators to etanercept initiators. We tested whether the adjusted HR differed by age, sex, race/ethnicity, body mass index, and smoking status.

Results

The crude incidence rate of serious infections per 100 person‐years was 5.4 (95%CI: 3.8, 7.5) in patients <65 years and 16.0 (95%CI: 10.4, 23.4) in patients ≥65 years during the first 3 months following treatment initiation. Compared with etanercept, the adjusted HR during this period was elevated for infliximab in patients <65 years (HR: 3.01; 95%CI: 1.49, 6.07), but not in those ≥65 years (HR 0.94; 95%CI: 0.41, 2.13). Findings did not suggest that the HR varied by the other patient characteristics examined.

Conclusions

An increased risk of serious infections associated with infliximab relative to etanercept did not appear to be modified by patients' sex, race/ethnicity, body mass index, or smoking status. There was an indication that the increased risk might be limited to patients <65 years. Additional studies are warranted to verify or refute this finding. Copyright © 2012 John Wiley & Sons, Ltd.
Practical method for estimating the power and energy delivered by photovoltaic modules operating under non‐standard conditions
Authors: Hernandez Johan , Vallejo William , Gordillo Gerardo
Published: March 2012

This work describes a method developed for estimating the energy delivered by building integrated photovoltaics systems operating under non‐standard conditions of irradiance and temperature. The method is based on calculation of the maximum power (PGmax) supplied by the modules array as a function of irradiance and ambient temperature, achieved by simulating its I–V and P–V curves using an algorithm which needs only the performance parameters supplied by the manufacturers. The energy generated by the PV system is estimated from monthly average values of PGmax calculated for using monthly average values of ambient temperature and irradiance obtained from data measured during 2 years. The method is applied to crystalline Si modules and tested by comparing the simulated I–V and P–V curves with those obtained by outdoor measurements as well as for comparing the energy produced during the years 2009 and 2010 with a 3.6 kWp building integrated photovoltaics system installed at the Universidad Nacional located in the city of Bogotá, Colombia, at 4°35′ latitude and 2.580 m altitude. The contrast of the simulated I–V and P–V curves for two different types of commercial Si‐modules with those experimentally obtained under real conditions indicated that the simulation method is reliably. Copyright © 2012 John Wiley & Sons, Ltd.
Hyperthermal Atomic Oxygen and Argon Modification of Polymer Surfaces Investigated by Molecular Dynamics Simulations
Authors: Kemper Travis W. , Sinnott Susan B.
Published: March 2012

The deposition of reactive and unreactive particles on polymer surfaces at hyperthermal incident energies is investigated using classical molecular dynamics simulations. The forces are calculated with the second‐generation reactive empirical bond‐order potential with modified parameters for C,H,O interactions. Three prototypical polymers, polyethylene (PE), polypropylene (PP) and polystyrene (PS), are modified by atomic oxygen and argon that are deposited with kinetic energies of 25, 50 and 100 eV. The non‐reactive argon is predicted to primarily break carbon–carbon bonds and remove hydrogen as a secondary process, while the reactive oxygen is more efficient at removing hydrogen during new bond formation with the polymer. The PE and PP are found to have similar responses to hyperthermal argon and oxygen deposition, while PS is found to be the most susceptible to oxygen modification.

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Effectiveness of sequencing selected exons of DNAH5 and DNAI1 in diagnosis of primary ciliary dyskinesia
Authors: Djakow Jana , Svobodová Tamara , Hrach Karel , Uhlík Jiří , Cinek Ondřej , Pohunek Petr
Published: March 2012

Introduction

Primary ciliary dyskinesia (PCD) is a rare genetically heterogenous condition. Mutations in DNAH5 or DNAI1 genes can be found in about a third of the patients with PCD. Increased occurrence of mutations was described in several exons of these long genes. The objective of the study was to test the sensitivity of sequencing of selected 13 exons (as compared to costly sequencing of all 100 exons of the two genes), and to determine the prevalence of the DNAH5 or DNAI1 mutations in the Czech PCD database.

Methods

The Czech national PCD database has identified 31 pediatric patients, diagnosed based on clinical findings and tests on the ciliated epithelium. Twenty‐seven patients from 24 families agreed on genetic testing. In the first step, direct sequencing of selected 13 exons (9 of DNAH5 and 4 of DNAI1) was performed, and then we compared its effectiveness in detecting at least one mutation with results of sequencing all 100 exons of the two genes.

Results

The sequencing of all exons identified compound heterozygosity for PCD mutations in nine patients from eight families (DNAH5 in eight and DNAI1 in one patient), and heterozygozity for a DNAH5 mutation of uncertain functional significance in one additional patient. The first step of selected exon sequencing detected a mutation in five out of these eight families, its actual sensitivity being 62.5%, with a high predictive value. The phenotypic and clinical characteristics of all the paediatric patients with PCD are shown.

Conclusions

Selected exon sequencing detects at least one mutated allele in over a half of our patients who have PCD due to DNAH5 or DNAI1 mutations. To lower the costs of the genetic testing, targeted step‐wise genetic testing may be a reasonable approach to detect mutations in PCD patients, especially if their phenotype is taken into account. Pediatr Pulmonol. 2012. 47:864–875. © 2012 Wiley Periodicals, Inc.
Vestibular and Motor Contributions to Mobility: Limitations of Seniors Awaiting Discharge from Hospital Care
Authors: Golder Michelle D. , Earl E. Marie , Mallery Laurie H.
Published: March 2012

Background and Purpose

Following hospitalization, seniors are at risk of impaired mobility and increased risk of falling, which can lead to injuries and re‐admission. The primary purpose of this paper was to evaluate the ability of hospitalized seniors to use vestibular inputs for balance control. The secondary purpose was to examine the influence of vestibular function and lower limb muscle strength on mobility.

Methods

Experimental and correlation designs were used. Patients (aged 65–90 years), preparing for discharge from an inpatient geriatric rehabilitation unit, were recruited. Vestibular control of standing balance was measured using the Clinical Test of Sensory Interaction for Balance (CTSIB). Mobility was measured with the Timed Up and Go (TUG) Test. Lower limb muscle maximum voluntary isometric contraction (MVIC) strength was tested with portable dynamometry. Wilcoxon signed rank test, with alpha adjusted for multiple comparisons (p ≤ 0.017), was used to compare relevant components of the CTSIB. Stepwise regression was used to assess the influence of vestibular impairment on TUG score.

Results

CTSIBTest6 (median = 7.1 seconds, range = 0.0–30.0) was less than CTSIBTest1 (30.0 seconds, 30.0–30.0) and CTSIBTest4 (30.0 seconds, 10.5–30.0) (W = 136, p < 0.017). MVIC scores (Nm·kg−1, mean ± SD) included hip abduction 0.38 ± 0.2, hip flexion 0.32 ± 0.1, hip extension 0.44 ± 0.2, knee flexion 0.31 ± 0.1, knee extension 0.33 ± 0.2, ankle dorsiflexion 0.12 ± 0.1 and ankle plantarflexion 0.23 ± 0.1. Mean TUG score was 26.1 ± 6.0 seconds. Performance on CTSIBTest6 explained 55% of the variance in TUG scores, whereas hip extension strength explained an additional 6%.

Conclusions

Seniors awaiting discharge from hospital had impaired vestibular control of balance that was systematically associated with impaired mobility. Evaluating vestibular function prior to discharge from hospital could improve discharge planning with respect to management of impairments that threaten balance and safe mobility. Copyright © 2012 John Wiley & Sons, Ltd.
Recent advances in F‐theory compactifications
Authors: Weigand T.
Published: March 2012

We review recent progress in the construction of F‐theory compactifications on elliptically fibered Calabi‐Yau 4‐folds. Of special importance is the resolution of the singularities in complex codimension one, two and three. These encode 7‐branes along holomorphic divisors carrying non‐abelian gauge groups, localised matter at the intersection of pairs of 7‐branes and Yukawa interactions, respectively. Toric methods admit the explicit construction of a large class of resolved 4‐folds. In particular the matter surfaces and interaction points can be analysed in great detail via resolution by blow‐up. Engineering chiral matter spectra requires non‐trivial gauge bundles described as certain types of G4‐fluxes. The recent construction of such fluxes paves the way for globally defined 3‐generation models e.g. of SU(5) GUT type, possibly including extra U(1) factors.
Conformal higher spin theory in extended tensorial superspace
Authors: Bandos I.A. , de Azcárraga J.A. , Meliveo C.
Published: March 2012

We discuss the formulation of free conformal higher spin theories with extended 𝒩 = 2, 4, 8 supersymmetry in 𝒩‐extended tensorial superspaces. The superfield higher spin equations can be obtained by quantizing a superparticle model in 𝒩‐extended tensorial superspace. The 𝒩‐extended higher spin supermultiplets just contain scalar and ‘spinor’ fields in tensorial space so that, in contrast with the standard (super)space approach, no nontrivial generalizations of the Maxwell or Einstein equations to tensorial space appear when 𝒩 > 2. For 𝒩 = 4, 8, the higher spin‐tensorial components of the extended tensorial superfields are expressed through additional scalar and spinor fields in tensorial space which obey the same free higher spin equations, but that are axion‐like in the sense that they possess Peccei‐Quinn‐like symmetries.
Role of dutasteride in pre‐clinical ETS fusion‐positive prostate cancer models
Authors: Ateeq Bushra , Vellaichamy Adaikkalam , Tomlins Scott A. , Wang Rui , Cao Qi , Lonigro Robert J. , Pienta Kenneth J. , Varambally Sooryanarayana
Published: March 2012

BACKGROUND

Androgens play a crucial role in prostate cancer, hence the androgenic pathway has become an important target of therapeutic intervention. Previously we discovered that gene fusions between the 5′‐untranslated region of androgen regulated gene TMPRSS2 and the ETS transcription factor family members were present in a majority of the prostate cancer cases. The resulting aberrant overexpression of ETS genes drives tumor progression.

METHODS

Here, we evaluated the expression levels of 5α‐reductase isoenzymes in prostate cancer cell lines and tissues. We tested the effect of dutasteride, a 5α‐reductase inhibitor, in TMPRSS2–ERG fusion‐positive VCaP cell proliferation and cell invasion. We also evaluated the effect of dutasteride on the TMPRSS2–ERG fusion gene expression. Finally, we tested dutasteride alone or in combination with an anti‐androgen in VCaP cell xenografts tumor model.

RESULTS

Our data showed that 5α‐reductase SRD5A1 and SRD5A3 isoenzymes that are responsible for the conversion of testosterone to DHT, are highly expressed in metastatic prostate cancer compared to benign and localized prostate cancer. Dutasteride treatment attenuated VCaP cell proliferation and invasion. VCaP cells pre‐treated with dutasteride showed a reduction in ERG and PSA expression. In vivo studies demonstrated that dutasteride in combination with the anti‐androgen bicalutamide significantly decreased tumor burden in VCaP cell xenograft model.

CONCLUSIONS

Our findings suggest that dutasteride can inhibit ERG fusion‐positive cell growth and in combination with anti‐androgen, significantly reduce the tumor burden. Our study suggests that anti‐androgens used in combination with dutasteride could synergistically augment the therapeutic efficacy in the treatment of ETS‐positive prostate cancer. Prostate 72:1542–1549, 2012. © 2012 Wiley Periodicals, Inc.
Influence of shape of GaN/AlN quantum dots on luminescence decay law
Authors: Aleksandrov I. A. , Gutakovskii A. K. , Zhuravlev K. S.
Published: March 2012

Photoluminescence (PL) kinetics of GaN quantum dots (QDs) in an AlN matrix has been investigated. We have found experimentally that the PL decay law of a GaN/AlN QD ensemble is non‐exponential in the single‐exciton recombination regime, and propose a model explaining the PL kinetics of GaN/AlN QD ensemble, which takes into account fluctuations of the QD shape.
Effects of Ce concentrations, annealing conditions and fabrication processes on the photoluminescence properties of Ce‐doped silica films
Authors: Cong Wei‐Yan , Zheng Wei‐Min , Li Su‐Mei , Wang Ying‐Jie , Liu Xiao‐Yan , Huang Hai‐Bei , Meng Xiang‐Yan , Zhai Jian‐Bo
Published: March 2012

Ce‐doped silica films with various Ce concentrations were prepared via ion beam sputtering (IBS) and ion implantation. The samples containing 1.46 at.% Ce were annealed at various temperatures from 500 to 1100 °C in air ambient and a separate sample with the same Ce concentration was annealed at 1100 °C in nitrogen gas. The Ce‐related photoluminescence (PL) was observed for the samples and found to be sensitive to the Ce concentrations, annealing conditions and fabricating processes. The PL intensity increases with increasing Ce concentrations from 0.09 to 0.58 at.%, and the concentration‐induced quenching effect occurred as the Ce concentrations reached 1.46 at.%. Also, the PL intensity is enhanced as the samples were annealed at various temperatures from 500 to 900 °C in air ambient, then decreases remarkably as the annealing temperature reached 1100 °C. In addition, compared with the sample annealed in air, the PL intensity can be enhanced for the sample annealed in nitrogen gas. Distinctive PL spectra were found for the samples prepared via different processes.
High field electron and hole transport in wurtzite InN
Authors: Reklaitis Antanas
Published: March 2012

A Monte Carlo technique has been used to investigate the steady‐state, transient, and small‐signal transport of electrons and holes in InN in high electric fields. The drift velocities and diffusion coefficients of electrons and holes are calculated using single‐particle Monte Carlo method. The transient drift velocities of electrons and holes are evaluated from ensemble Monte Carlo simulations. The electron small‐signal mobility is estimated. The threshold frequency of 550 GHz for the negative differential mobility (NDM) in InN is obtained.
Silicon heterojunction solar cell with amorphous silicon oxide buffer and microcrystalline silicon oxide contact layers
Authors: Ding Kaining , Aeberhard Urs , Finger Friedhelm , Rau Uwe
Published: March 2012

This Letter reports on the fabrication and characterization of silicon heterojunction solar cells with silicon oxide based buffer (intrinsic amorphous silicon oxide) and contact layers (doped microcrystalline silicon oxide) on flat p‐type wafers. The critical dependency of the cell performance on the front and rear buffer layer thickness reveals a trade‐off between the open circuit voltage Voc and the fill factor FF. At the optimum, the highest efficiency of 18.5% (active area = 0.67 cm2) was achieved with Voc = 664 mV, short circuit current Jsc = 35.7 mA/cm2 and FF = 78.0%. (© 2012 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Defect‐band photoluminescence imaging on multi‐crystalline silicon wafers
Authors: Yan Fei , Johnston Steve , Zaunbrecher Katherine , Al‐Jassim Mowafak , Sidelkheir Omar , Ounadjela Kamel
Published: March 2012

Defect‐band emission photoluminescence (PL) imaging with an indium‐gallium‐arsenide (InGaAs) camera was applied to multi‐crystalline silicon (mc‐Si) wafers, which were taken from different heights of different Si bricks. Neighboring wafers were picked at six different processing steps, from as‐cut to post‐metallization. By using different cut‐off filters, we were able to separate the band‐to‐band emission images from the defect‐band emission images. On the defect‐band emission images, the bright regions that originate from extend‐ ed defects were extracted from the PL images. The area fraction percentage of these regions at various processing stages shows a correlation with the final cell electrical parameters. (© 2012 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)