bluuebunny/crossref_metadata_2025_split huggingface dataset:
Design of MIMO antenna positions for mobile handset when considering nondeterministic channels
Authors: Uthansakul Peerapong , Assanuk Danai , Uthansakul Monthippa 
Published: September 2011

AbstractThe topic of practical implementation of multiple input multiple output (MIMO) systems for mobile communications has recently gained a lot of attention.Due to the area constraint on a mobile handset, the problem of how to design such a system in order to achieve the best benefit is still a huge challenge. Most researches in this area concern the algorithms to configure the best layout of multiple antennas while assume the wireless channel as the deterministic model. However, mobile users might roam from one channel condition to the others, which the benefit of deterministic antenna positions does no longer exist. In this article, the concern of channel variation has been included in the process of finding MIMO antenna positions. A genetic algorithm (GA) is employed to find the optimal antenna positions on mobile handset for 4 × 4 MIMO systems. The effects of mutual coupling based on Z‐parameter is the main factor to determine the MIMO capacity concerning as the objective function of GA search. The results suggest that the use of average positions among solutions obtained by various channels provide the most compromising benefits to practically design MIMO antenna positions on mobile handset. © 2011 Wiley Periodicals, Inc. Microwave Opt Technol Lett 53:2737–2742, 2011; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.26402
Micromachinned monopole antenna by CMOS‐Compatible deep trench technology
Authors: Wang Tao , Lu Shey‐Shi 
Published: September 2011

AbstractA monopole antenna fabricated by standard 0.18 μm CMOS technology is post‐IC processed by CMOS compatible inductively coupled plasma etching, which can remove the silicon substrate selectively under the metal strips. After substrate release, the resonance of the monopole antenna reveals owing to elimination of the energy confinement from the high‐dielectric media. Experimental results show an improvement of input return loss (S11) from −9 to –14.3 dB by such substrate release technique. The power transfer ratio also increases from 0.87 to 0.96 for better radiation efficiency. © 2011 Wiley Periodicals, Inc. Microwave Opt Technol Lett 53:2971–2973, 2011; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.26403
Wideband planar slotted radiating ground plane antenna for portable devices
Authors: Sonkki Marko , Antonino‐Daviu Eva , Ferrando‐Bataller Miguel , Salonen Erkki T. 
Published: September 2011

AbstractA method for exciting currents in a radiating ground plane over a wide frequency bandwidth is presented. Using a complementary slot in the ground plane excited by a closely spaced monopole (0.008–0.05λ) with 50 Ω input impedance, a wide frequency bandwidth can be achieved to cover multiple radio interfaces. © 2011 Wiley Periodicals, Inc. Microwave Opt Technol Lett 53:2854–2858, 2011; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.26408
A CPW‐fed annular slot‐antenna with an L‐shaped strip
Authors: Chang The‐Nan 
Published: September 2011

AbstractA slot‐ring with any type of asymmetry can support more than one mode. Based on this simple observation, a short coplanar waveguide (CPW)‐fed annular slot‐antenna backed by an L‐shaped strip is investigated in this article. On one hand, the annular slot‐ring with a backed L‐shaped strip and without the shorted stub is enough to generate a circularly polarized (CP) wave. On the other hand, the annular slot‐ring with a shorted stub and without the backed L‐shaped strip is enough to yield a broadband operation. In this article, we integrate both types of asymmetry in an annular slot‐ring. We can achieve 10 dB return loss bandwidth from 2.4 to 4.5 GHz. Within this wide band, a CP wave is observed at the 2.45 GHz band. © 2011 Wiley Periodicals, Inc. Microwave Opt Technol Lett 53:2821–2827, 2011; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.26416
Ultra‐broad and multiband 3D‐monopole antennas
Authors: Elsheakh Dalia M. , Safwat Amr M. E. 
Published: September 2011

AbstractNovel three‐dimensional antennas that provide either multibands or ultra‐broadband are presented. The proposed structures are based on monopole antennas loaded with meander lines. For operation of multibands, the monopole is loaded with different‐length meander lines connected in series. The proposed antenna has 55 × 66 × 130 mm3 volume and operates in the following bands: 200 MHz, 800 MHz, 1.1 GHz, 1.4 GHz, 2.45 GHz, 3 GHz, and 3.7 GHz. Ultra‐broadband is achieved by connecting four monopoles in parallel. Each monopole is loaded with two meander lines. The resulting bandwidth extends from 400 MHz to 3.5 GHz, which is suitable for digital video broadcasting‐T applications, and the size is 53 × 68 × 87 mm3. Both antennas have omnidirectional radiation patterns. © 2011 Wiley Periodicals, Inc. Microwave Opt Technol Lett 53:2843–2846, 2011; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.26417
UMTS diplexer design using the antiparallel‐coupled lines loaded with a stepped impedance resonator
Authors: Ho Min‐Hua , Lin Wei‐Chen 
Published: September 2011

AbstractWe present a novel UMTS diplexer design using the filters of antiparallel‐coupled lines structure loaded with a stepped impedance microstrip resonator. The diplexer is composed of two filters. And a microstrip line of quarter‐wavelength is used to links each filter to the common port. The composing filters exhibit two tunable transmission zeros which are used to implement the mid‐passband zero implantation for improving the isolation between the transmitting (Tx) and the receiving (Rx) ports. A pair of spurlines is used in the coupled lines of the Tx‐filter to further increase the isolation. An experiment is conducted to assure the diplexer's performance and to verify the circuit design. © 2011 Wiley Periodicals, Inc. Microwave Opt Technol Lett 53:2988–2990, 2011; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.26421
Frequency‐tunable terahertz electromagnetic‐pulses generation based on an optical Fabry–Perot microresonator with variable birefringence material
Authors: Chen Ming 
Published: September 2011

AbstractA frequency‐tunable terahertz (THz)‐frequency electromagnetic‐pulses generation method is proposed based on an optical Fabry–Perot (FP) microresonator with variable birefringence materials. At the output FP microcavity, polarization mode beat with high‐frequency can be achieved due to the phase mismatch effect of the two polarization modes in the birefringence materials in the FP cavity. One can generate frequency‐tunable electromagnetic pulse radiation through changing the birefringence of the materials. When the birefringence changed from 3.7355 × 10−4 to 7.4710 × 10−2, electromagnetic‐pulses with frequencies from 0.05 to 10.0 THz can be obtained. © 2011 Wiley Periodicals, Inc. Microwave Opt Technol Lett 53:2879–2882, 2011; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.26422
Optical millimeter‐wave generation based on an external modulator
Authors: Zhu Jia Hu , Huang Xu Guang 
Published: September 2011

AbstractOptical millimeter‐wave (mm‐wave) generation based on an external modulator is proposed and simulately demonstrated.Both theoretical analysis and simulation results reveal that doubling‐frequency, quadrupling‐frequency, sextupling‐frequency, octupling‐frequency, decupling‐frequency, 12‐fold‐frequency, dual quadrupling‐frequency, or dual octupling‐frequency mm‐waves can be generated in this scheme. The frequency of local oscillator signal is largely reduced because frequency octupling, frequency decupling, or frequency 12‐fold mm‐wave is generated. The overall cost of the system is largely reduced. © 2011 Wiley Periodicals, Inc. Microwave Opt Technol Lett 53:2902–;2907, 2011; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.26432
A dual‐band RF front end for DVB‐H direct conversion receiver
Authors: Jung Seung Hwan , Eo Yunseong 
Published: September 2011

AbstractA dual‐band RF front end for the DVB‐H direct conversion receiver is implemented using 0.18‐μm CMOS technology. To achieve the low‐NF and high‐IIP3 performance, the LO stage of the passive mixer is optimized with respect to the transistor size and gate bias. The measured results show that the NF is below 4.8 dB and the IIP3 at low‐noise amplifier off state is above +3.5 dBm all over the bands. The chip size is 0.75 mm2 excluding pads and the current consumption is 5.6 and 6 mA at 1.8 V supply, respectively. © 2011 Wiley Periodicals, Inc. Microwave Opt Technol Lett 53:2796–2799, 2011; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.26438
Allowing for missing outcome data and incomplete uptake of randomised interventions, with application to an Internet‐based alcohol trial
Authors: White Ian R. , Kalaitzaki Eleftheria , Thompson Simon G. 
Published: September 2011

Missing outcome data and incomplete uptake of randomised interventions are common problems, which complicate the analysis and interpretation of randomised controlled trials, and are rarely addressed well in practice. To promote the implementation of recent methodological developments, we describe sequences of randomisation‐based analyses that can be used to explore both issues. We illustrate these in an Internet‐based trial evaluating the use of a new interactive website for those seeking help to reduce their alcohol consumption, in which the primary outcome was available for less than half of the participants and uptake of the intervention was limited.For missing outcome data, we first employ data on intermediate outcomes and intervention use to make a missing at random assumption more plausible, with analyses based on general estimating equations, mixed models and multiple imputation. We then use data on the ease of obtaining outcome data and sensitivity analyses to explore departures from the missing at random assumption. For incomplete uptake of randomised interventions, we estimate structural mean models by using instrumental variable methods.In the alcohol trial, there is no evidence of benefit unless rather extreme assumptions are made about the missing data nor an important benefit in more extensive users of the intervention. These findings considerably aid the interpretation of the trial's results. More generally, the analyses proposed are applicable to many trials with missing outcome data or incomplete intervention uptake. To facilitate use by others, Stata code is provided for all methods. Copyright © 2011 John Wiley & Sons, Ltd.
Locally Advanced Mid/Low Rectal Cancer with Synchronous Liver Metastases
Authors: Viganò Luca , Karoui Mehdi , Ferrero Alessandro , Tayar Claude , Cherqui Daniel , Capussotti Lorenzo 
Published: September 2011

AbstractBackgroundManagement of patients with T3/4 and/or N+ mid/low rectal cancer with synchronous liver metastases is not codified. The aim of this study was to analyze outcomes of our approach which consists of neoadjuvant chemotherapy or chemoradiotherapy, according to liver disease extension, followed by simultaneous rectal and liver resection.MethodsBetween 2000 and 2009, 354 patients underwent hepatectomy for synchronous metastases. Thirty‐six consecutive patients who underwent rectal and liver resection for metastatic T3/4 and/or N+ mid/low rectal cancer were analyzed.ResultsLiver metastases were multiple in 27 patients, bilobar in 22, and >5 cm in six. Up‐front treatment was chemotherapy in 15 patients, chemoradiotherapy in seven, chemotherapy followed by chemoradiotherapy in six, and surgery in eight (five symptomatic tumors). After chemotherapy alone (median number of cycles = 6), primary tumor response was observed in 11 patients (three complete responses). After chemoradiotherapy, only one patient had liver disease progression. Eighty‐nine percent of patients underwent simultaneous rectal and hepatic resection. Mortality and morbidity rates were 2.8% (one pulmonary embolism) and 36%, respectively. After a mean follow‐up of 39 months, 5‐year overall and disease‐free survival were 59.3 and 39.6%, respectively. Twenty‐one patients had recurrence, including three pelvic recurrences (8.3%). No pelvic recurrence occurred among patients who correctly completed treatment strategy. All patients who received neoadjuvant chemoradiotherapy were alive and disease‐free; 5‐year overall and disease‐free survival of patients receiving neoadjuvant chemotherapy were 59.3 and 25%, respectively.ConclusionsFor patients with metastatic T3/4 and/or N+ mid/low rectal cancer, the present strategy was safe and effective. Good disease control was achieved by neoadjuvant treatments, low morbidity rates were associated with simultaneous resection, and excellent long‐term outcomes with low local relapse rate were obtained.
Robotic Versus Open Pancreaticoduodenectomy: A Comparative Study at a Single Institution
Authors: Buchs Nicolas Christian , Addeo Pietro , Bianco Francesco Maria , Ayloo Subhashini , Benedetti Enrico , Giulianotti Pier Cristoforo 
Published: September 2011

AbstractBackgroundMinimally invasive pancreaticoduodenectomy (PD) remains one of the most challenging abdominal procedures, and its application is poorly reported in the literature so far. To date, few data are available comparing a minimally invasive approach to open PD. The aim of the present study is to compare the robotic and open approaches for PD at a single institution.MethodsData from 83 consecutive PD procedures performed between January 2002 and May 2010 at a single institution were retrospectively reviewed. Patients were stratified into two groups: the open group (n = 39; 47%) and the robotic group (n = 44; 53%).ResultsPatients in the robotic group were statistically older (63 years of age versus 56 years; p = 0.04) and heavier (body mass index: 27.7 vs. 24.8; p = 0.01); and had a higher American Society of Anesthesiologists (ASA) score (2.5 vs. 2.15; p = 0.01) when compared to the open group. Indications for surgery were the same in both groups. The robotic group had a significantly shorter operative time (444 vs. 559 min; p = 0.0001), reduced blood loss (387 vs. 827 ml; p = 0.0001), and a higher number of lymph nodes harvested (16.8 vs. 11; p = 0.02) compared to the open group. There was no significant difference between the two groups in terms of complication rates, mortality rates, and hospital stay.ConclusionsThe authors present one of the first studies comparing open and robotic PD. While it is too early to draw definitive conclusions concerning the long‐term outcomes, short‐term results show a positive trend in favor of the robotic approach without compromising the oncological principles associated with the open approach.
Value creation and pricing in buyouts: Empirical evidence from Europe and North America
Authors: Achleitner Ann‐Kristin , Braun Reiner , Engel Nico 
Published: September 2011

AbstractUsing a unique proprietary data set of 1980 realized and unrealized buyouts completed between 1986 and 2010, we examine entry and exit pricing in buyouts and its influence on private equity (PE) sponsors' returns. We find that besides leverage and operational improvements, EBITDA multiple expansion (i.e. the difference between entry and exit pricing) is a fundamental factor in explaining equity returns and the result of skill rather than pure luck. We also provide evidence that more experienced PE sponsors use more debt to finance a PE transaction and debt is positively related to entry buyout pricing. However, for a transaction with a given leverage level, more experienced PE sponsors are able to negotiate lower prices. In addition, our results show that deals conducted by first time funds which are realized in a later stage of a fund's life cycle are associated with lower exit prices which can be explained by the increased exit pressure for the PE sponsor.
Predictive validity of pharmacologic interventions in animal models of neuropathic pain
Authors: Honoré Per Hartvig , Basnet Anna , Kristensen Pernille , Andersen Lene Munkholm , Neustrup Signe , Møllgaard Pia , Eljaja Laila , Bjerrum Ole J. 
Published: September 2011

Abstract

Introduction
The pathophysiologic and neurochemical characteristics of neuropathic pain must be considered in the search for new treatment targets. Breakthroughs in the understanding of the structural and biochemical changes in neuropathy have opened up possibilities to explore new treatment paradigms. However, long term sequels from the damage are still difficult to treat.

Aim of the study
To examine the validity of pharmacological treatments in humans and animals for neuropathic pain.

Method
An overview from the literature and own experiences of pharmacological treatments employed to interfere in pain behavior in different animal models was performed.

Results
The treatment principles tested in animal models of neuropathic pain may have predictive validity for treatment of human neuropathies. Opioids, neurotransmitter blockers, drugs interfering with the prostaglandin syntheses as well as voltage gated sodium channel blockers and calcium channel blockers are treatment principles having efficacy and similar potency in humans and in animals. Alternative targets have been identified and have shown promising results in the validated animal models. Modulators of the glutamate system with an increased expression of glutamate re-uptake transporters, inhibition of pain promoters as nitric oxide and prostaglandins need further exploration. Modulation of cytokines and neurotrophins in neuropathic pain implies new targets for study. Further, a combination of different analgesic treatments may as well improve management of neuropathic pain, changing the benefit/risk ratio.

Implications
Not surprisingly most pharmacologic principles that are tested in animal models of neuropathic pain are also found to be active in humans. Whereas many candidate drugs that were promising in animal models of neuropathic pain turned out not to be effective or too toxic in humans, animal models for neuropathic pain are still the best tools available to learn more about mechanisms of neuropathic pain. Better understanding of pathogenesis is the most hopeful approach to improve treatment of neuropathic pain.
A novel triazolic naphthofuranquinone induces autophagy in reservosomes and impairment of mitosis in Trypanosoma cruzi
Authors: FERNANDES M. C. , DA SILVA E. N. , PINTO A. V. , DE CASTRO S. L. , MENNA-BARRETO R. F. S. 
Published: September 2011

SUMMARYChagas' disease, caused by the protozoan Trypanosoma cruzi, represents a serious health problem in Latin America, and the available chemotherapy, which is based on 2 nitro-derivatives, is not satisfactory. In folk medicine, natural products including naphthoquinones have been employed for the treatment of different parasitic diseases. In the pursuit of alternative drugs for Chagas' disease, we investigated the mechanism of action of the triazolic naphthoquinone (TN; 2,2-dimethyl-3-(4-phenyl-1H-1,2,3-triazol-1-yl)-2,3-dihydronaphtho[1,2-b]furan-4,5-dione), which is the most active compound against T. cruzi trypomastigotes among a series of naphthofuranquinones. TN was active against the 3 parasite forms producing a dose-dependent inhibitory effect. In epimastigotes, TN induced reservosome disruption, flagellar blebbing, Golgi disorganization, the presence of cytosolic concentric membrane structures and abnormal multiflagellar parasites. The treatment also led to the appearance of well-developed endoplasmic reticulum profiles surrounding organelles that associated with an increase in monodansylcadaverine labelling, suggesting autophagy as part of the TN mechanism of action. Interestingly, no ultrastructural damage was detected in the mitochondria of naphthoquinone-treated epimastigotes. Flow cytometric analysis demonstrated an impairment of mitosis, an increase in ROS production and the maintenance of mitochondrial membrane potential. TN could be a good starting point in the investigation of a chemotherapeutic approach for the treatment of Chagas' disease.
Effective elements of cognitive behaviour therapy for psychosis: results of a novel type of subgroup analysis based on principal stratification
Authors: Dunn G. , Fowler D. , Rollinson R. , Freeman D. , Kuipers E. , Smith B. , Steel C. , Onwumere J. , Jolley S. , Garety P. , Bebbington P. 
Published: September 2011

BackgroundMeta-analyses show that cognitive behaviour therapy for psychosis (CBT-P) improves distressing positive symptoms. However, it is a complex intervention involving a range of techniques. No previous study has assessed the delivery of the different elements of treatment and their effect on outcome. Our aim was to assess the differential effect of type of treatment delivered on the effectiveness of CBT-P, using novel statistical methodology.MethodThe Psychological Prevention of Relapse in Psychosis (PRP) trial was a multi-centre randomized controlled trial (RCT) that compared CBT-P with treatment as usual (TAU). Therapy was manualized, and detailed evaluations of therapy delivery and client engagement were made. Follow-up assessments were made at 12 and 24 months. In a planned analysis, we applied principal stratification (involving structural equation modelling with finite mixtures) to estimate intention-to-treat (ITT) effects for subgroups of participants, defined by qualitative and quantitative differences in receipt of therapy, while maintaining the constraints of randomization.ResultsConsistent delivery of full therapy, including specific cognitive and behavioural techniques, was associated with clinically and statistically significant increases in months in remission, and decreases in psychotic and affective symptoms. Delivery of partial therapy involving engagement and assessment was not effective.ConclusionsOur analyses suggest that CBT-P is of significant benefit on multiple outcomes to patients able to engage in the full range of therapy procedures. The novel statistical methods illustrated in this report have general application to the evaluation of heterogeneity in the effects of treatment.
Spatial receptive field properties of rat retinal ganglion cells
Authors: HEINE WALTER F. , PASSAGLIA CHRISTOPHER L. 
Published: September 2011

AbstractThe rat is a popular animal model for vision research, yet there is little quantitative information about the physiological properties of the cells that provide its brain with visual input, the retinal ganglion cells. It is not clear whether rats even possess the full complement of ganglion cell types found in other mammals. Since such information is important for evaluating rodent models of visual disease and elucidating the function of homologous and heterologous cells in different animals, we recorded from rat ganglion cells in vivo and systematically measured their spatial receptive field (RF) properties using spot, annulus, and grating patterns. Most of the recorded cells bore likeness to cat X and Y cells, exhibiting brisk responses, center-surround RFs, and linear or nonlinear spatial summation. The others resembled various types of mammalian W cell, including local-edge-detector cells, suppressed-by-contrast cells, and an unusual type with an ON–OFF surround. They generally exhibited sluggish responses, larger RFs, and lower responsiveness. The peak responsivity of brisk-nonlinear (Y-type) cells was around twice that of brisk-linear (X-type) cells and several fold that of sluggish cells. The RF size of brisk-linear and brisk-nonlinear cells was indistinguishable, with average center and surround diameters of 5.6 ± 1.3 and 26.4 ± 11.3 deg, respectively. In contrast, the center diameter of recorded sluggish cells averaged 12.8 ± 7.9 deg. The homogeneous RF size of rat brisk cells is unlike that of cat X and Y cells, and its implication regarding the putative roles of these two ganglion cell types in visual signaling is discussed.