bluuebunny/crossref_metadata_2025 huggingface dataset:
Towards Combating Poaching in the South African Abalone Fishery
Authors: Giesler A , Joseph‐Malherbe S M
Published: August 2015

The challenges to the habitat and marine life of the South African coast are many and varied, for example climate changes, animal/fish population cycle variations, development and recreational demands, subsistence harvesters, traditional poaching culture in some communities, poverty, problems associated with natural disasters, oil spills, mining activities, and criminal enterprises. One of the biggest problems facing South Africa's marine life is poaching, which is the focal point of this paper.

This paper proposes a technology enabler to assist with combating poaching. It is based on unmanned surface vehicles (USV) with sensors that patrol identified areas for poaching activities. This USV has a communication system that relays information real‐time from the sensors to a control room where it is monitored. The control room is in contact with enforcement agencies. The interconnection of planning systems, monitoring sensors and visualization tools will enable quick reaction and orchestrated response to threats by one or more of the enforcement agencies.
Generic Model‐Based Systems Engineering Methodology
Authors: Meyer Bernhard
Published: August 2015

This paper presents a Generic Model‐Based Systems Engineering (G‐MBSE) approach based on an application of generic systems engineering principles. Firstly, these principles are defined, described and illustrated in more detail. Important artefacts are introduced that describe and characterise a system, e.g. system hierarchy, black box and white box system descriptions. Secondly, a generic systems engineering process is described within the context of a customised V‐Model variant. This process is then augmented with a model‐based validation/verification process to help reduce uncertainty and rework with the later design implementation. Ideally, model‐based validation/verification should eliminate most of the deficiencies from, and confirm suitability of the solution/specification. Thirdly, some examples of typical artefacts required for a generic model‐based implementation are presented, which have to be supported by a tool‐based approach. Finally, an appraisal concludes feasibility of the proposed approach, ready for tool support.
Common terminology, well established techniques and methods are key success factors of Requirements Engineering: the contribution of RE certification to project success
Authors: Salinesi Camille , Sturm Stefan
Published: August 2015

As numerous studies, such as the well‐known Chaos report by the Standish Group, show it, Requirements Engineering (RE) is among the main key success factors of ICT projects. In order to improve project success a stronger focus has to be set on the early project phases, i.e. the Requirements Engineering. With several specialised international conferences series and scientific journals, the literature offers a wealth of research findings from novel methods, techniques and tools, to case study reports, surveys, experiment reports, literature reviews, etc. Many professional books have been published, and mature tools are available on the market. How comes with all this material, the profession does not get the appropriate attention? How comes people who need to practice RE lack so frequently of even the basic knowledge in RE? The position taken in this paper is that a common understanding of the terminology and of widely acknowledged techniques and methods can be established through certification, which in its turns shall contribute to better project success. Starting from an analysis of the salient problems, the paper describes the driving principles of certification, and shows its implementation with the IREB CPRE (Certified Professional in Requirements Engineering) scheme. Based on testimony by a sample from the 16.000+ IREB certified people shows the papers demonstrates the multiple outcome of being CPRE: improved project management, increased customer and user satisfaction, more innovative products and services among others.
Making new and integrated sense of heterogeneous pre‐eclampsia
Authors: Smith Gary Robert
Published: August 2015

Pre‐eclampsia is a dangerous condition that effects around 3‐8% of all pregnancies. Due to the complexity of its origin, condition and relationships with a host of factors it is colloquially known as the “disease of theories”. Arguably well established reductionist approaches inherent in the domain of disease treatment have as yet been unable to unravel this problem and the only effective treatment currently available is early delivery of the foetus and placenta. Systems Thinking however is claimed as a vehicle for tackling complex problems and as a framework for seeing interrelationships rather than isolated things and events. Elaborating on a new paradigm of systems thinking established from cancer and taking into account other emerging works of new thinking for pre‐eclampsia, proposals are made that might prove useful for the understanding and potential treatment of the condition.
Applying Systems Thinking in shaping South Africa's Electricity System
Authors: Stoker PW , Fick JIJ
Published: August 2015

The paper analyses the current situation in respect of South Africa's electricity situation and asks the question if Systems Thinking, more specifically as it pertains to the theory of Complex Adaptive Systems, would make a contribution to improved Electrical Energy decision making.

The authors applied a specific branch of Complex Adaptive Systems (namely “edge of chaos” theory) by following an example based argumentative approach in their research. This led to the following observations:

Information in respect of Electrical Energy and South Africa's Gross Domestic Product (GDP) as presented in the National Development Plan, Integrated Energy Plan and Integrated Resource Plan appears to be inconsistent.

The sensitivity of Energy Intensity, the (lack of) accuracy with which it can be forecasted, and its alignment with expected growth sectors in the South African economy should be well understood and carefully monitored in shaping the future of the country's Electricity System.

The paper concludes that the mental framework which Systems Thinking provides, and specifically the theory which explains the behavior of Complex Adaptive Systems, could make a positive contribution towards achieving quicker coherence in respect of South Africa's future Electricity System. Furthermore that such coherence will lead to quicker emergence of the single most important characteristic of the “RSA (Incorporated) system” ‐ its economic growth.
The case for nuclear electricity in South Africa – An economic view
Authors: Stoker PW , Fick JIJ , Ndube LK , Tlape N , Vuba M
Published: August 2015

This paper makes the economic case for nuclear electricity in South Africa. The importance to the economy of having clean, reliable and affordable electricity serves as background against which the case is made for the cost for electricity by means of nuclear generation.

The aim of the paper is to provide a realistic, objective and honest prediction of the Levelised Cost of Electricity (LCOE) which could be expected from deployment of two 1600MWe reactors on the Thyspunt site. The paper does not follow the traditional approach whereby sensitivity analysis is performed on key LCOE parameters such as construction time and discount rate. It rather assumes realistic values for these parameters, based on global indicators and taking account of the South African context. It describes pre‐requisite conditions that must be met for these assumptions to be valid. The authors submit that this approach is typical of the systems approach to resolving highly complex intra‐disciplinary problems.

The paper proposes a project capitalization plan and reports the calculated LCOE generated by a nuclear plant at R1.28/kWh.

It is concluded that an advanced capitalization plan holds many advantages, but these come at the price of very complex contractual arrangements. It was further argued that pre‐requisites for such advanced capitalization schemes include a stable socio‐political situation, predictable legislative environment and a vibrant economy.
A Case Study into the status of Requirements Management in the South African defence industry
Authors: Surju Sunil , Benade Siebert
Published: August 2015

In the systems engineering domain, there are several processes that are necessary for success, one of them is requirements engineering. This is a study of the requirements management process, traceability tools and workforce in the defence environment. A review of the literature suggested that good requirements management is important for success in projects; tools can be an enabler and the workforce can negatively or positively influence the requirements process. The author is an employee of Armscor and works on capital acquisition programmes in a project management capacity. Prior investigations within Armscor, the acquisition and procurement agency for the Department of Defence (DOD), revealed that problems exists in managing requirements internal and externally. The objective of this research was to determine the extent of these problems specifically focussed on the requirements process, the supporting tools and the workforce influences. The research followed a multiple case study strategy. It was a qualitative study with semi‐structured interviews conducted with respondents from four organisations i.e. DOD, Armscor and two Defence Industry Organisations namely DIO1 and DIO2. The results revealed that the requirements processes on the higher organisational levels required improvements and the problems discussed in the literature review were similar; tools played an important role in facilitating good requirements management and creating traceability. The workforce issues contributed largely to poor requirements management.
A Systems Engineering approach for the deployment of an atmospheric monitoring station
Authors: Venter A.D. , Stoker P.W. , Fick J.I.J. , Vakkari V. , van Zyl P.G. , Beukes J.P. , Laakso L.
Published: August 2015

In this paper the importance of a Systems Engineering (SE) approach is reiterated for developing and managing an atmospheric monitoring station. A newly established comprehensive atmospheric monitoring station, the Welgegund Atmospheric Monitoring Station (WAMS), was used as a case study ‐ system of interest (SOI). In agreement with commercial projects, the Customer Need has shown that the SOI life‐cycle may be time intensive with significant financial impacts. The Operational Concept was visualised in terms of physical requirements, operational methodology and final deliverables. Functional Analysis emphasised the design importance of the measurement station for continuous operation and to remain relevant throughout the system life‐cycle. Physical architectures and interfaces were scrutinised to maximise the efficiency of the SOI. Testing was vital and remains a continuous process. By continuing to implement the SE approach, the WAMS will satisfy the changing and unique stakeholder requirements throughout the system life‐cycle. The paper concludes that the SE framework provided made a positive contribution since the initial design and has adequately identified all the requirements in order for WAMS to be implemented on time, within budget and to the level of performance required.
Communicating with the C‐Suite: Turning Systems Engineer‐Speak into Executive‐Speak
Authors: Walden David D.
Published: August 2015

Communication is an essential soft skill of the Systems Engineer. Systems Engineers are called upon to communicate with numerous internal and external stakeholders. Sometimes a Systems Engineer has to communicate to top‐level senior executives. They are often known as the C‐Suite, since many of the executives’ titles start with “C,” for Chief (e.g., Chief Executive Officer, Chief Operating Officer, Chief Information Officer). This paper describes several ways in which Systems Engineers can be more effective in communicating with the C‐Suite.
Introducing the INCOSE Systems Engineering Handbook Version 4
Authors: Walden David D. , Roedler Garry J. , Forsberg Kevin
Published: August 2015

The objective of the International Council on Systems Engineering (INCOSE) Systems Engineering Handbook is to describe key process activities performed by systems engineers and other engineering professionals throughout the life cycle of a system. It also describes a wide range of fundamental system concepts that broaden the thinking of the systems engineering practitioner, such as system thinking, system science, life cycle management, specialty engineering, system‐of‐systems, and complex systems. This handbook defines the discipline and practice of systems engineering for students and practicing professionals alike, providing an authoritative reference that is acknowledged world‐wide.

Editors of the Systems Engineering Handbook will give an overview of Version 4 that is scheduled to be released in January of 2015. They will describe the overall impetus for change, highlight changes from the previous versions, and describe the new content added for this version.
Four Mantras: Teacher Language That Honors Students With Disabilities
Authors: Hudson Debra A. , Gritter Kristine
Published: August 2015

This column features essays written by current middle school and high school teachers, media specialists, librarians, literacy coaches, curriculum specialists, administrators, preservice teachers, teacher educators, and adolescent and adult learners. They highlight diverse perspectives on teaching and/or learning with literacies to inspire reader reflection.
Prevascularized silicon membranes for the enhancement of transport to implanted medical devices
Authors: Worthington Kristan S. , Wiley Luke A. , Mullins Robert F. , Tucker Budd A. , Nuxoll Eric
Published: August 2015

Recent advances in drug delivery and sensing devices for in situ applications are limited by the diffusion‐limiting foreign body response of fibrous encapsulation. In this study, we fabricated prevascularized synthetic device ports to help mitigate this limitation. Membranes with rectilinear arrays of square pores with widths ranging from 40 to 200 μm were created using materials (50 μm thick double‐sided polished silicon) and processes (photolithography and directed reactive ion etching) common in the manufacturing of microfabricated sensors. Vascular endothelial cells responded to membrane geometry by either forming vascular tubes that extended through the pore or completely filling membrane pores after 4 days in culture. Although tube formation began to predominate overgrowth around 75 μm and continued to increase at even larger pore sizes, tubes formed at these large pore sizes were not completely round and had relatively thin walls. Thus, the optimum range of pore size for prevascularization of these membranes was estimated to be 75–100 μm. This study lays the foundation for creating a prevascularized port that can be used to reduce fibrous encapsulation and thus enhance diffusion to implanted medical devices and sensors. © 2015 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 104B: 1602–1609, 2016.
Monodispers and Multifunctional Magnetic Composite Core Shell Microspheres for Demulsification Applications
Authors: Ali Nisar , Zhang Baoliang , Zhang Hepeng , Zaman Wajed , Ali Sarmad , Ali Zafar , Li Wei , Zhang Qiuyu
Published: August 2015

Iron oxide@Poly(Glycidylmethacrylate‐methyl methacrylate‐divinyl benzene) magnetic composite core shell microspheres Fe3O4@P(GMA‐MMA‐DVB) with epoxy group on the surface was designed and synthesized by solvothermal process followed by distillation polymerization. The surface epoxy group was modified with amino group of ethylene diamine (EDA) to prepare Fe3O4@P(GMA‐MMA‐DVB)/NH2 microspheres, and then effects of modification on the structure, interfacial behavior and hence demulsification of the amino modified epoxy coating were examined. The prepared magnetic microspheres were characterized using a laser particle size analyzer, transmission electron microscopy, Fourier transform infrared spectroscopy, vibrating sample magnetometry, and thermogravimetric analysis. Fourier transform infrared spectrometer analysis indicates the presence of epoxy group, amino group and Fe3O4 in the final Fe3O4@P(GMA‐MMA‐DVB) and Fe3O4@P(GMA‐MMA‐DVB)/NH2 magnetic core shell microspheres. Our experimental results show that Fe3O4@P(GMA‐MMA‐DVB)/NH2 magnetic core shell microspheres exhibit good interfacial and demulsification properties and able to remove emulsified water from stable emulsion. The resulting microspheres showed excellent magnetic properties and further these can be recycled and reused by magnetic separation.
On the Strongest Form of a Theorem of Whitney for Hamiltonian Cycles in Plane Triangulations
Authors: Brinkmann Gunnar , Souffriau Jasper , Van Cleemput Nico
Published: August 2015

In this article, we investigate hamiltonian cycles in plane triangulations. The aim of the article is to find the strongest possible form of Whitney's theorem about hamiltonian triangulations in terms of the decomposition tree defined by separating triangles. We will decide on the existence of nonhamiltonian triangulations with given decomposition trees for all trees except trees with exactly one vertex with degree and all other degrees at most 3. For these cases, we show that it is sufficient to decide on the existence of nonhamiltonian triangulations with decomposition tree K1, 4 or K1, 5. We also give computational results on the size of a possible minimal nonhamiltonian triangulation with these decomposition trees.
[2 + 2] Cycloaddition Reactions of Butadienyl Ketene with 1,4‐Diazabuta‐1,3‐dienes: Synthesis of Functionalized Butadienyl‐4‐iminomethyl‐azetidin‐2‐ones and Butenylidene‐butadienyl‐[2,2′‐biazetidine]‐4,4′‐diones
Authors: Bains Deepak , Kumar Yogesh , Singh Prabhpreet , Bhargava Gaurav
Published: August 2015

The reactions of butadienylketene with variety of 1,4‐diazabuta‐1,3‐dienes are studied. The reactions resulted in the formation of previously unknown functionalized cis butadienyl‐4‐iminomethyl‐azetidin‐2‐ones and butenylidene‐butadienyl‐[2,2′‐biazetidine]‐4,4′‐ diones. Butadienyl ketene reacts in [2+2] cycloaddition fashion with both iminic portion of 1,4‐ diazabuta‐1,3‐dienes and competitive [4+2] cycloaddition reaction of 1,4‐diazabuta‐1,3‐dienes as 4π component with butadienyl ketene as 2π component are not observed.
Surgical site infection impact of pelvic exenteration procedure
Authors: Moghadamyeghaneh Zhobin , Hwang Grace S. , Hanna Mark H. , Carmichael Joseph C. , Mills Steven , Pigazzi Alessio , Stamos Michael J.
Published: August 2015

Background

We sought to investigate morbidity and infectious complications following pelvic exenteration (PEx) and compare infectious complications of patients undergoing PEx and conventional rectal resections.

Methods

The NSQIP database was utilized to examine the clinical data of patients undergoing elective rectal resections during 2005–2013. Multivariate regression analysis was used to compare postoperative complications of patients who underwent PEx and proctectomy procedure.

Results

We sampled a total of 7,950 patients who underwent rectal resection. Of these, 303 (3.8%) patients underwent pelvic exenteration. Mortality, morbidity, and infectious complications of patients who underwent pelvic exenteration were 1.7%, 65.7%, and 42.6%, respectively. Patients who underwent PEx had a significantly higher rate of morbidity (AOR: 2.01, P < 0.01), overall infectious complications (AOR: 1.49, P < 0.01), hemorrhagic complications (AOR: 3.36, P < 0.01), and surgical site infections (SSI) (AOR: 1.23, P = 0.04) compared to patients who underwent proctectomy. Return to operation room (AOR: 4.99, P < 0.01), obesity (AOR: 1.43, P < 0.01), disseminated cancer (AOR: 1.30, P = 0.01) were significantly associated with SSI complications.

Conclusion

Postoperative morbidity and infectious complication are significantly higher after PEx procedure. Return to operation room, obesity, and disseminated cancer are strongly associated with surgical site infections complications in rectal surgery. Specific consideration to infectious complications is recommended for these patients. J. Surg. Oncol. 2015; 112:533–537. © 2015 Wiley Periodicals, Inc.
Simultaneous quantitation of two diastereoisomers of lobaplatin in rat plasma by supercritical fluid chromatography with tandem mass spectrometry and its application to a pharmacokinetic study
Authors: Meng Xiangjun , Yang Bo , Gao Jingyi , Peng Wenwen , Wang Hao , Shi Meiyun , Mortishire‐Smith Russell , Yang Yan , Gu Jingkai
Published: August 2015

Lobaplatin, consisting of two diastereoisomers, is a third‐generation platinum antineoplastic agent that has shown encouraging anticancer activity in a variety of tumor types. To investigate any stereospecificity in the pharmacokinetics of lobaplatin, a novel, simple, rapid and sensitive supercritical fluid chromatography with tandem mass spectrometry method was developed for the simultaneous quantitation of lobaplatin diastereoisomers in rat plasma. After a simple protein precipitation with methanol, the analytes and dexpantoprazole (internal standard) were chromatographed on an Acquity UPC2 system with a Chiralcel OZ‐RH column using a mobile phase consisting of carbon dioxide and methanol (65:35, v/v) at 40°C over 6 min. The assay was linear over a concentration range of 25–15 000 ng/mL for both diastereoisomers using 100 μL of rat plasma for sample preparation. The lower limit of quantification was 25 ng/mL for both compounds, which was sufficient to detect the diastereoisomers in the incurred samples within this study. Intra‐ and inter‐day precisions were below 11.8% and the accuracies were below 4.5%. The validated method was successfully applied to a pharmacokinetic study after an intravenous administration of 7.6 mg/kg lobaplatin to rats. There was no apparent stereospecificity in the pharmacokinetics between the two diastereoisomers of lobaplatin.
Main Environmental Features Leading to Recent Land Abandonment in Murcia Region (Southeast Spain)
Authors: Alonso‐Sarría Francisco , Martínez‐Hernández Carlos , Romero‐Díaz Asunción , Cánovas‐García Fulgencio , Gomariz‐Castillo Francisco
Published: August 2015

Land abandonment is a global phenomenon whose environmental consequences are difficult to assess. The Murcia region is one of the most arid regions in southern Europe and also one of the most prone to land abandonment. This study researches which environmental features are more relevant to explain abandonment at the agricultural plot scale. Geomorphometric features were measured at different scales to investigate which scales could be more relevant. Two different models have been used: logistic regression, a statistical model that allows the interpretation of the involved features, and Random Forest, a machine learning model with a higher predictive power but lower interpretability. The combined use of both such models allows a set of predictors to be selected, which, when used with Random Forest, produce a map that is highly accurate for predicting abandonment and, when used with logistic regression, produce an interpretable model. The main conclusion is that climate is the most relevant factor to explain land abandonment. Copyright © 2015 John Wiley & Sons, Ltd.
Progression of mouse skin carcinogenesis is associated with the orchestrated deregulation of mir‐200 family members, mir‐205 and their common targets
Authors: Skourti Elena , Logotheti Stella , Kontos Christos K. , Pavlopoulou Athanasia , Dimoragka Paraskevi T. , Trougakos Ioannis P. , Gorgoulis Vassilis , Scorilas Andreas , Michalopoulos Ioannis , Zoumpourlis Vassilis
Published: August 2015

MicroRNAs are small, non‐coding RNAs which regulate post‐transcriptionally hundreds of target mRNAs. Given that their expression is deregulated in several cancer types, they represent potential diagnostic, prognostic, and predictive biomarkers, as well as next‐generation therapeutic targets. Nevertheless, the involvement of miRNAs in non‐melanoma skin cancer, a cancer type with increasing prevalence, is not extensively studied, and their comprehensive characterization as regard to the initiation, promotion, and progression stages is missing. To this end, we exploited a well‐established multistage mouse skin carcinogenesis model in order to identify miRNAs consistently implicated in different stages of skin carcinogenesis. The cell lines comprising this model were subjected to miRNA expression profiling using microarrays, followed by bioinformatics analysis and validation with Q‐PCR, as well as treatment with miRNA modulators. We showed that among all deregulated miRNAs in our system, only a functionally coherent group consisting of the miR‐200 family members and miR‐205‐5p displays a pattern of progressive co‐downregulation from the early toward the most aggressive stages of carcinogenesis. Their overlapping, co‐regulated putative targets are potentially inter‐associated and, of these, the EMT‐related Rap1a is overexpressed toward aggressive stages. Ectopic expression of miR‐205‐5p in spindle cancer cells reduces Rap1a, mitigates cell invasiveness, decreases proliferation, and delays tumor onset. We conclude that deregulation of this miRNA group is primarily associated with aggressive phenotypes of skin cancer cells. Restoration of the miR‐205‐5p member of this group in spindle cells reduces the expression of critical, co‐regulated targets that favor cancer progression, thus reversing the EMT characteristics. © 2015 Wiley Periodicals, Inc.
Therapeutic Developments for Tics and Myoclonus
Authors: Jankovic Joseph
Published: August 2015

Tics and myoclonus are phenomenologically similar given that both are jerk‐like movements, but, in contrast to myoclonus, tics are often preceded by premonitory sensations and are typically associated with a variety of behavioral comorbidities, including attention deficit and obsessive‐compulsive disorder. There are many other clinical features that help differentiate these two hyperkinetic disorders. Whereas behavioral and antidopaminergic therapies are most effective in the management of tics, clonazepam, other anticonvulsants, and serotonergic drugs are often used to control myoclonic movements. Botulinum toxin may also be helpful in focal tics and in segmental forms of myoclonus. DBS plays an increasingly important role in the treatment of these disorders, particularly when they are generalized and are disabling despite optimal medical therapy. © 2015 International Parkinson and Movement Disorder Society
Body mass index mediates inflammatory response to acute dietary challenges
Authors: Matone Alice , O'Grada Colm M. , Dillon Eugene T. , Morris Ciara , Ryan Miriam F. , Walsh Marianne , Gibney Eileen R. , Brennan Lorraine , Gibney Michael J. , Morine Melissa J. , Roche Helen M.
Published: August 2015

Scope

Acute metabolic challenges provide an opportunity to identify mechanisms of metabolic and nutritional health. In this study, we assessed the transcriptomic response to oral glucose and lipid challenges in a cohort of individuals ranging in age and BMI. The main goal is to identify whether BMI can mediate the metabolic and transcriptional response to dietary challenges, and the differences between lipid and glucose tests.

Methods and results

Two hundred fourteen healthy adults were assigned to the challenges and twenty‐three individuals were selected for further transcriptomic proofing, using microarray analysis of peripheral blood mononuclear cells. Through linear‐mixed models and network analysis, different sets of transcripts and pathways were identified that responded to the challenges depending on BMI. Different transcripts that responded to the lipid and glucose tests, independently of BMI, were also identified. In the network analysis, inflammatory and adhesion processes were strongly represented for both challenges.

Conclusion

Our results indicate that BMI is strongly linked to the transcriptomic and metabolic response to acute challenges. The emerging biological processes are mainly inflammation‐related pathways, highlighting an interconnection between obesity, inflammation/adhesion, and response to nutritional challenge. The comparison between lipid and glucose challenges shows how these trigger a substantially different molecular response.
A compact multiband reject inverted double‐E microstrip filter on textile substrate
Authors: Cavalcante Gustavo A. , Minervino Diego R. , D'Assunção Adaildo G. , Neto Valdemir P. Silva , D'Assunção Adaildo G.
Published: August 2015

This article presents the development of textile compact microstrip filters using jeans fabric dielectric substrates and pure copper polyester taffeta fabric conducting strips. Microstrip circuits such as antennas, filters, and frequency selective surfaces on textile materials exhibit some advantages over the traditional ones on microwave dielectric substrates, such as high flexibility, low weight, low cost, and easy fabrication. The proposed textile filter with inverted double‐E geometry is analyzed using the wave concept iterative procedure (WCIP), a full‐wave method, and through Ansoft Designer software. Filters with multiband reject performance are designed. For the purpose of validation, prototypes are manufactured and measured. Simulation (WCIP and Ansoft Designer) and measurement results are in excellent agreement. © 2015 Wiley Periodicals, Inc. Microwave Opt Technol Lett 55:2543–2548, 2015
A compact antenna with frequency and pattern reconfigurable characteristics
Authors: Pan Yong , Ma Yongta , Xiong Jiang , Hou Ziye , Zeng Yue
Published: August 2015

This article proposes a compact printed frequency and pattern reconfigurable antenna. The antenna has a low profile, low cost, and small size of 58.0 × 40.0 × 1.2 mm3, and mainly consists of dual symmetrical radiators, two rectangle parasitic elements and one inverted T‐shape ground plane which may acts as a reflector. By loading the parasitic elements and selecting different radiators to connect to the feed, the proposed antenna can switch among three operating frequencies (2.01–2.26 GHz, 2.28–2.52 GHz, and 3.73–4.02 GHz) and select patterns between two kinds of radiating patterns with main lobe directions of
and
in the xoy plane. Comparing the expected results with measured results, a good agreement is obtained. © 2015 Wiley Periodicals, Inc. Microwave Opt Technol Lett 55:2467–2471, 2015
Semifractal antenna with dual‐bands filtering and circular polarization properties using SCBP and MDGS structures
Authors: Naser‐Moghadasi M. , Sedgeechongaraluye‐Yekan T.
Published: August 2015

This article proposes the novel design of a coplanar waveguide fed (CPW‐Fed) monopole ultra wideband (UWB) semifractal antenna with dual band‐notched specification and circular polarization (CP) attributes at ITU‐R (7.725–8.5 GHz). The semifractal patch of antenna is composed of unitcell which unitcell patterns form branchs of tree. The fractal geometry in radiator leads to have an effective impedance matching over the UWB spectrum. The Dual‐band filtering property can be adjusted finely by embedding a pair of L‐strips length inside the slotted conductor‐backed‐plane (SCBP) and mirrored defected ground structure (MDGS). Beside that, the length and position of L‐strips have great role in achieving CP in ITU‐R band. The actual size of the miniature and fabricated antenna is limited to 15 × 15 × 1 mm3 and it operates across 2.2–12.52 GHz for S11<−10dB, except the bandwidths of 3.1–3.6 for WiMAX and 5–6 GHz for WLAN. The antenna has CP bandwidth from 7.5 to 8.5 GHz for axial ratio less than 3 dB. The antenna's parameters were investigated to fully understand their affects. Main parameters achieved from this analysis enabled the optimization of the antenna's entire performances. The prototype was fabricated, to validate the performance of antenna, through simulations and measurements. The measured results certify the antenna radiates omnidirectionally and has a large impedance bandwidth, dual‐band rejection and CP property. © 2015 Wiley Periodicals, Inc. Microwave Opt Technol Lett 55:2483–2487, 2015
Miniature low SAR printed monopole antenna for mobile phone
Authors: Hossain M. I. , Faruque M. R. I. , Islam M. T.
Published: August 2015

A multiband compact printed monopole antenna is proposed for mobile phone. In this configuration, the antenna comprises a slotted rectangular‐shaped radiator, microstrip‐fed line, and a slotted ground plane on FR‐4 substrate. The total antenna dimensions with ground plane are 78 × 40 × 0.8 mm3. The measured results show that the proposed antenna has an impedance bandwidth 358.4 MHz (0.60–0.95 GHz, lower band), and 1 GHz (1.7–2.7 GHz, upper band), which can cover GSM 900 MHz, DCS 1800 MHz, PCS 1900 MHz, GSM 1900 MHz, UMTS 2100 MHz, Bluetooth 2400 MHz, WLAN II.b (2400 MHz), and LTE (2300–2400 MHz) bands. The proposed antenna shows very good radiation efficiencies and gain values and near omnidirectional radiation patterns at those frequency bands. Moreover, the proposed antenna produces lower specific absorption rate values in the human head than that of a dipole antenna, helical antenna, and planar inverted‐F antenna. © 2015 Wiley Periodicals, Inc. Microwave Opt Technol Lett 55:2471–2475, 2015
UWB loop antenna with stable broadside radiation characteristics
Authors: Yeo Junho , Lee Jong‐Ig
Published: August 2015

In this article, a circular loop antenna with stable broadside radiation characteristics for ultrawideband (UWB) applications is proposed. It consists of a circular loop and circular sectors, and the circular sectors are used to directly match a 50‐Ω feed line over a UWB frequency band. The geometry of the proposed antenna is optimized to cover the 3.1–10.6 GHz UWB frequency band with stable broadside radiation patterns. The input impedance and voltage standing wave ratio (VSWR) characteristics of three different structures (a center‐fed circular loop with thin strips, a structure with circular sectors as an end‐truncated semicircular dipole, and the proposed loop antenna with circular sectors) are compared. The optimized proposed antenna is fabricated on a Teflon substrate. It exhibits a measured impedance frequency band of 3.08–12.27 GHz (120%) for a VSWR < 2, which ensures operation in the UWB band. Measured broadside gain is 3.0–7.0 dBi, and stable broadside radiation patterns are observed in the entire UWB band. Measured group delay remains almost constant with a variation of less than ±0.5 ns for the face‐to‐face orientation, and this indicates good time domain performance of the antenna. © 2015 Wiley Periodicals, Inc. Microwave Opt Technol Lett 55:2515–2519, 2015
A novel tunable microwave filter integrated power dividers using liquid crystal
Authors: Jiang Di , Chen Hui , Li Xiang , He Zhaosheng , Shen Mengkui
Published: August 2015

This article presents design considerations of a tunable microwave filter integrated power divider based on highly anisotropic liquid crystals (LCs), which helps to reduce the circuit size. The proposed device comprising a thin LC layer between a ground plane and a directly coupled inverted microstrip line exhibits the equal power splitting function with a tunable bandpass response. The integrated device results in sharp rejection and smaller circuit area, as compared with the cascaded connection of an equal power divider and tunable microwave filter. © 2015 Wiley Periodicals, Inc. Microwave Opt Technol Lett 55:2539–2543, 2015
A 60 GHz transformer‐coupled neutralized low power CMOS power amplifier
Authors: Chen Bo , Shen Li , Gao Jianjun
Published: August 2015

A 60 GHz transformer‐coupled class AB 3‐stage low power amplifier (PA) has been implemented in a 130 nm standard RF‐CMOS process. The transformer, featuring direct impedance transformation and power combining is suitable for 60 GHz power amplifier design. This power amplifier operates from 1.2 V supply with 9.9 dB gain at 62 GHz, dissipates 58 mW DC power, and the reverse isolation is better than 39 dB from 50 to 67 GHz. © 2015 Wiley Periodicals, Inc. Microwave Opt Technol Lett 55:2487–2491, 2015
Band‐notched CPW‐FED UWB antenna using V‐shaped fractal elements
Authors: Esmati Zahra , Moosazadeh Mahdi
Published: August 2015

A simple procedure for designing a new fractal CPW‐fed monopole antenna with band‐notch function for ultrawideband applications has been proposed. The proposed antenna consists of V‐shaped patch with circular‐shaped elements and an elliptically‐shaped tapered ground plane. To create band‐notch function, V‐shaped structure is extruded on the patch from the throat of the feed. By cutting a pair of a quarter ellipse‐shaped slots in the ground plane, proper impedance matching is obtained; as a result much wider impedance bandwidth can be achieved, especially at the higher frequencies. The antenna is small in size (25 × 25 mm2) and has wide usable fractional bandwidth of more than 143% (3.15–19 GHz) defined by VSWR < 2, except at frequency band‐notched of 4.90–6.04 GHz. Moreover, Omnidirectional radiation pattern and acceptable antenna gain are obtained over the operating band. © 2015 Wiley Periodicals, Inc. Microwave Opt Technol Lett 55:2533–2536, 2015
A compact CPW‐FED wideband metamaterial antenna with EBG loading
Authors: Gupta Ashish , Chaudhary Raghvendra Kumar
Published: August 2015

Two wideband CPW‐fed metamaterial antenna structures based on CRLH resonant approach are proposed and developed in this article. Antenna‐1 is basically an asymmetric CPW‐fed antenna, comprises of meandered line inductor, which is connected between patch and one of the CPW ground plane. Antenna‐2 is modified form of Antenna‐1 where conventional uniplanar electromagnetic bandgap (EBG) structures have been incorporated to enhance bandwidth of the antenna. It has been observed that Antenna‐2 is operating at 4.84–10.64 GHz equivalent to 74.9% measured fractional bandwidth with respect to Antenna‐1 with operating frequency 5.03–8.39 GHz equivalent to 50.1% fractional bandwidth. It is demonstrated that surface waves are suppressed effectively in the extended band. The radiation patterns of the Antenna‐2 are not influenced significantly with the incorporation of EBG and offers consistent radiation patterns throughout the operational bandwidth. © 2015 Wiley Periodicals, Inc. Microwave Opt Technol Lett 55:2632–2636, 2015
An accurate effective radius formula based on taguchi method for calculating resonant frequency of electrically thin and thick circular patch antennas
Authors: Li Xiaofeng , Wang Zhongbao , Fang Shaojun
Published: August 2015

A novel effective radius formula is proposed for accurately calculating the resonant frequency of circular patch antennas with electrically thin and thick substrates. The formula is optimized and obtained using the Taguchi method. It is widely suitable to circular patch antennas with the electrical substrate thickness h/λd range from 0.001 to 0.2 and the dielectric constants range from 1.0 to 10.2. Compared with previous resonant frequency analysis formulae, the resonant frequency results calculated using the proposed effective radius formula are in a better agreement with the simulated and measured results. © 2015 Wiley Periodicals, Inc. Microwave Opt Technol Lett 55:2567–2572, 2015
Hybrid dual‐antenna for the 3.6‐GHz LTE operation in the tablet computer
Authors: Wong Kin‐Lu , Chang Hsuan‐Jui
Published: August 2015

A hybrid dual‐antenna formed by an inverted‐F antenna (IFA) and an open‐slot antenna (OSA) for the 3.6‐GHz LTE operation (3.4–3.8 GHz) in the tablet computer is presented. The dual‐antenna is printed on a 0.8‐mm thick FR4 substrate and has a compact planar structure of 4 × 30 mm2. The dual‐antenna comprises a clearance region wherein the IFA is disposed and a metal pad wherein the OSA is embedded. The IFA's shorting strip is grounded through the metal pad to the device ground plane, so that an integrated compact dual‐antenna structure is obtained. As the IFA and OSA have different excitation mechanisms (electric‐current excitation on the IFA vs. magnetic‐current excitation on the OSA), the two antennas are expected to have different near‐field characteristics, thereby leading to decreased coupling. The proposed dual‐antenna has a measured isolation of better than about 12 dB over the operating band. The IFA and OSA have measured antenna efficiencies of about 72%–86% and 57%–78%, respectively. Good envelope correlation coefficient of less than 0.1 is obtained. Over the operating band, the ergodic capacity of the dual‐antenna is calculated to be about 9.8–10.6 bps/Hz. Details of the proposed dual‐antenna are presented. © 2015 Wiley Periodicals, Inc. Microwave Opt Technol Lett 55:2592–2598, 2015
A design of single‐ended to differential‐ended power divider for X band application
Authors: Yu Yongxia , Sun Liguo
Published: August 2015

A five‐port power divider with single‐ended input and two differential‐ended outputs is proposed. The frequency ranges from 9 to 11 GHz with a central frequency of 10 GHz. A stepped impedance line with open stubs is used between differential pairs for broadening the bandwidth and miniaturization of the divider. The divider is fabricated and the measurement results comply with the simulation. A proper performance for differential mode signal is achieved. The insertion loss is within 1.8 dB, the isolation is more than 15 dB, and the return loss is more than 11 dB. In addition, the common mode suppression is reached as well. © 2015 Wiley Periodicals, Inc. Microwave Opt Technol Lett 55:2669–2673, 2015
Wideband double‐negative reconfigurable metamaterial using a complementary split‐ring resonator with a via‐hole
Authors: Choi Jung Han , Jung Chang Won
Published: August 2015

We demonstrate a wideband reconfigurable double‐negative metamaterial using a complementary split‐ring resonator with a via‐hole in a planar microstrip line. The resonator is made of quad‐rings, which are grounded using the via‐hole. By tailoring the quad‐rings with switches, reconfigurability was implemented and the isotropic nature was investigated. The equivalent circuit was proposed. The effective permittivity and permeability were extracted using the Ziolkowski method. Excellent agreements between the developed circuit model and experiment results were achieved. © 2015 Wiley Periodicals, Inc. Microwave Opt Technol Lett 55:2687–2690, 2015
A compact hut‐shaped printed antenna for super‐wideband applications
Authors: Tahir Farooq A. , Naqvi Aqeel H.
Published: August 2015

In this article, a novel super‐wideband planar microstrip‐fed monopole antenna is investigated and designed. The antenna consists of a well‐optimized hut‐shaped radiating patch having a diamond‐shaped slot window at its center. To achieve nearly omnidirectional pattern, a partial ground plane consisting of an optimized slit exactly on the opposite of the feed line is used. Measurement results show that the impedance bandwidth for |S11|dB ≤ 10 dB is enhanced largely to 184.5% with a ratio bandwidth more than 24.8:1 (0.9 − 22.35 GHz). This, together with its nearly constant measured gain of 3.35 dBi ±1 dB over this entire band makes it a potential candidate for both ultra‐wideband and super‐wideband applications. Moreover, the proposed antenna has a compact size of 40 × 25 mm2 on 1.6 mm thick FR4 substrate with dielectric constant of 4.4. Details of the proposed antenna are described, and both theoretical and experimental results are presented. © 2015 Wiley Periodicals, Inc. Microwave Opt Technol Lett 55:2645–2649, 2015
Low cost electronic beam tilting of microstrip antennas by the use of tunable parasites
Authors: Dias Mauricio Henrique Costa , Freitas Vitor , Vuong Tan‐Phu
Published: August 2015

In this work, parasitic elements are combined with inserted capacitances to tilt the radiated beam of a microstrip patch antenna. An application case at 2.45 GHz was considered for discussion. Realized gains up to 8 dBi and tilts within ±15° were achieved by the proposed configuration. © 2015 Wiley Periodicals, Inc. Microwave Opt Technol Lett 55:2710–2713, 2015
Zero‐biased diode Schottky detector for low cost preamplified millimeter‐wave imaging
Authors: Yang Fei , Wang Zongxin , Dou WenBin , Sun Zhongliang
Published: August 2015

Development of a sensitive Schottky detector using zero‐biased diode (ZBD) for preamplified millimeter‐wave imaging is presented. Low noise amplifier gain and detector responsivity, key parameters to the imaging module, are analyzed to get the sensitivity performance characterization. The detector integrates one ZBD, stripline filtering and matching elements, and finline transition on a thin Rogers substract. Methodology used to detector design is described here, including the determination and optimization of the circuit geometrical and electrical parameters. A relatively good agreement between the simulations and the measurements has been found. At 92 GHz, linearity of 0.998 and detection responsivity of 4000 mV/mW dB are measured, respectively. © 2015 Wiley Periodicals, Inc. Microwave Opt Technol Lett 55:2690–2693, 2015
Isolated facial diplegia in Guillain–Barré syndrome: Bifacial weakness with paresthesias
Authors: Wakerley Benjamin R. , Yuki Nobuhiro
Published: August 2015

Bifacial weakness with paresthesias (BFP) is a subtype of Guillain–Barré syndrome defined by rapidly progressive bilateral facial weakness in the absence of other cranial neuropathies, ataxia, or limb weakness. Many patients also complain of distal limb paresthesias and display diminished or absent deep tendon reflexes. BFP is a localized form of Guillain–Barré syndrome and is thought to be caused exclusively by demyelinating‐ rather than axonal‐type neuropathy. Patients with BFP do not display anti‐ganglioside IgG antibodies. Since it is rare, many physicians are unfamiliar with BFP, as bilateral facial weakness is more commonly associated with sarcoidosis, Lyme disease, or meningeal pathology. Many patients diagnosed with bilateral Bell palsy may instead have BFP. In this review, we highlight the clinical features of BFP and outline diagnostic criteria. Muscle Nerve 52: 927–932, 2015
Balance and coordination training, but not endurance training, enhances synaptophysin and neurotrophin‐3 immunoreactivity in the lumbar spinal cord after sciatic nerve crush
Authors: Bonetti Leandro Viçosa , Ilha Jocemar , Schneider Ana Paula Krauthein , Barbosa Silvia , Faccioni‐Heuser Maria Cristina
Published: August 2015

Introduction: Numerous rehabilitation treatments have been shown to be useful for peripheral and central restoration after (PNI). Methods: After sciatic nerve crush, we investigated 4 weeks of endurance training (ET) and balance and coordination training (BCT) with sciatic function index, hind‐paw stride length, and spinal cord dorsal horn synaptophysin and neurotrophin‐3 immunoreactivity. Results: Our results demonstrated no significant differences between the non‐trained (NT), ET, and BCT groups in sciatic functional index, and in stride‐length analysis, but the ET showed higher values compared with the NT group. Synaptophysin immunoreactivity was higher in the BCT group compared with the NT group, and neurotrophin‐3 immunoreactivity in the BCT group was greater compared with the other groups. Conclusion: BCT can positively affect spinal cord plasticity after a (PNI), and these modifications are important in the rehabilitation process. Muscle Nerve 53: 617–625, 2016