bluuebunny/crossref_metadata_2025_split huggingface dataset:
Bioactivity and Viscoelastic Characterization of Chitosan/Bioglass® Composite Membranes
Authors: Caridade Sofia G. , Merino Esther G. , Alves Natália M. , Mano João F. 
Published: June 2012

AbstractMembranes of chitosan (CTS) and composite membranes of CTS with bioglass are prepared by solvent casting. The composite membranes are shown to induce the precipitation of apatite upon immersion in SBF. The biomineralization process is followed by measuring the variation of the viscoelastic properties of the membranes immersed in SBF, both online and offline. Non‐conventional DMA is used to measure the change in the storage modulus, E′, and the loss factor, tan δ, as a function of the immersion in SBF. A simple model is used to estimate the E′ of the apatite layer formed in vitro that is about 130 MPa. This work shows that innovate mechanical tests can be useful to characterize the mechanical performance of composites under physiological conditions. magnified image
Modification of Polydimethylsiloxane Coatings by H2 RF Plasma, Xe2* Excimer VUV Radiation, and Low‐Energy Electron Beams
Authors: Swiderek Petra , Jolondz Evgeni , Bredehöft Jan Hendrik , Borrmann Tobias , Dölle Christopher , Ott Matthias , Schmüser Christoph , Hartwig Andreas , Danilov Vladimir , Wagner Hans‐Erich , Meichsner Jürgen 
Published: June 2012

AbstractThe crosslinking of thin liquid PDMS layers by three different technically relevant processes, H2 radio‐frequency plasma treatment, Xe2* excimer VUV irradiation, and low‐energy electron beam processing is investigated. The modifications to the layers due to the processing are monitored by means of RAIRS. Plasma processing of liquid PDMS leads to a direct conversion to a SiOx‐like material of the topmost layers, whereas a gradual transition from PDMS to the same product is observed upon VUV irradiation. Electron exposure does not induce oxidation. The initiating steps of the conversion induced by the interaction with VUV photons, low‐energy electrons, or their combined effect with ions and H atoms in the plasma are discussed. The latter creates a high density of damage sites. magnified image
Lycopene inhibits angiogenesis both in vitro and in vivo by inhibiting MMP‐2/uPA system through VEGFR2‐mediated PI3K‐Akt and ERK/p38 signaling pathways
Authors: Chen Man‐Ling , Lin Yu‐Hsiu , Yang Chih‐Min , Hu Miao‐Lin 
Published: June 2012

ScopeLimited in vitro data show that lycopene may be anti‐angiogenic but with unclear mechanisms. Here, we employed ex vivo and in vivo assays to substantiate the anti‐angiogenic action of lycopene and determined its molecular mechanisms in human umbilical vein endothelial cells (HUVECs).Methods and resultsThe anti‐angiogenic activity of lycopene was confirmed by ex vivo rat aortic ring and in vivo chorioallantoic membrane assays. Furthermore, the in vivo matrigel plug assay in mice demonstrated that lycopene implanted s.c. at the highest dose used (400 μg/plug) completely inhibited the formation of vascular endothelial cells induced by vascular endothelial growth factor (VEGF). As expected, lycopene inhibited tube formation, invasion, and migration in HUVECs, and such actions were accompanied by reduced activities of matrix metalloproteinase‐2, urokinase‐type plasminogen activator, and protein expression of Rac1, and by enhancing protein expression of tissue inhibitors of metalloproteinase‐2 and plasminogen activator inhibitor‐1. Moreover, lycopene attenuated VEGF receptor‐2 (VEGFR2)‐mediated phosphorylation of extracellular signal‐regulated kinase (ERK), p38, and Akt as well as protein expression of PI3K.ConclusionOur data demonstrate the anti‐angiogenic effect of lycopene both in vitro and in vivo. The anti‐angiogenic activity of lycopene may involve inhibition of MMP‐2/uPA system through VEGFR2‐mediated PI3K‐Akt and ERK/p38 signaling pathways.
Phytoestrogens genistein and daidzein affect immunity in the nematode Caenorhabditis elegans via alterations of vitellogenin expression
Authors: Fischer Malaika , Regitz Charlotte , Kahl Mareike , Werthebach Michael , Boll Michael , Wenzel Uwe 
Published: June 2012

ScopePhytoestrogens, such as the soy isoflavones genistein and daidzein, are suggested to beneficially affect lipid metabolism in humans and thereby contribute to healthy ageing. New evidences show that phytoestrogens might slow ageing processes also by affecting immune processes.Methods and resultsWe tested in the nematode Caenorhabditis elegans the effects of 17β‐estradiol, genistein, and daidzein on resistance versus the nematode pathogen Photorhabdus luminescens with focus on vitellogenins, which are invertebrate estrogen‐responsive genes that encode homologues to ApoB100 with impact on immune functions. Here, we show that the estrogen 17β‐estradiol increases the resistance of C. elegans versus P. luminescens by enhancing vitellogenin‐expression at the mRNA and protein level. Knockdown of single out of five functional vits by RNA‐interference blunted the life‐extending effects under heat‐stress of 17β‐estradiol, demonstrating a lack of redundancy for the vitellogenins. RNAi for nhr‐14, a suggested nuclear hormone receptor for estrogens, displayed no influence on 17β‐estradiol effects. The soy isoflavone genistein reduced vitellogenin‐expression and also resistance versus P. luminescens whereas daidzein increased resistance versus the pathogen in a vitellogenin‐dependent manner.ConclusionOur studies show that induction of estrogen‐responsive vitellogenin(s) by the phytoestrogen daidzein potently increases resistance of C. elegans versus pathogenic bacteria and heat whereas genistein acts in an antiestrogenic manner.
Dietary rice bran component γ‐oryzanol inhibits tumor growth in tumor‐bearing mice
Authors: Kim Sung Phil , Kang Mi Young , Nam Seok Hyun , Friedman Mendel 
Published: June 2012

ScopeWe investigated the effects of rice bran and components on tumor growth in mice.Methods and resultsMice fed standard diets supplemented with rice bran, γ‐oryzanol, Ricetrienol®, ferulic acid, or phytic acid for 2 weeks were inoculated with CT‐26 colon cancer cells and fed the same diet for two additional weeks. Tumor mass was significantly lower in the γ‐oryzanol and less so in the phytic acid group. Tumor inhibition was associated with the following biomarkers: increases in cytolytic activity of splenic natural killer (NK) cells; partial restoration of nitric oxide production and phagocytosis in peritoneal macrophages increases in released the pro‐inflammatory cytokines tumor necrosis factor‐α, IL‐1β, and IL‐6 from macrophages; and reductions in the number of blood vessels inside the tumor. Pro‐angiogenic biomarkers vascular endothelial growth factor (VEGF), cyclooxygenase‐2 (COX‐2), and 5‐lipoxygenase‐5 (5‐LOX) were also significantly reduced in mRNA and protein expression by tumor genes. ELISA of tumor cells confirmed reduced expression of COX‐2 and 5‐LOX up to 30%. Reduced COX‐2 and 5‐LOX expression downregulated VEGF and inhibited neoangiogenesis inside the tumors.ConclusionInduction of NK activity, activation of macrophages, and inhibition of angiogenesis seem to contribute to the inhibitory mechanism of tumor regression by γ‐oryzanol.
Integration of miniaturized balun and low‐noise amplifier for single‐in differential‐out applications
Authors: Yang Chin‐Lung , Chiang Ming‐Jeng , Chiang Yi‐Chyun 
Published: June 2012

AbstractA low‐noise module comprises a low‐noise amplifier and a new type of passive balun, which consists of two λ/8 broadside‐coupled lines and a short redundant line, is presented. The on‐chip balun is not only low lossy and compact size but also provides good amplitude and phase balances at output ports over a quite wide frequency range. The method of designing the new‐type balun fabricated with CMOS IC technology is proposed. An experimental prototype operated at K‐band was designed and fabricated with a commercial 0.18‐μm CMOS technology to verify the effectiveness of the proposed design method. The measured results show the single‐to‐differential gain is about 9 dB, the amplitude imbalance of the output ports is less than 1.0 dB associated with the phase difference of 181 ± 3° over the frequency range of 20–40 GHz. The area of the prototype including the RF probe pads is about 0.73 × 1.28 mm2. © 2012 Wiley Periodicals, Inc. Microwave Opt Technol Lett 54:2117–2121, 2012; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.26987
A planar CPW‐fed patch antenna on thin substrate for broadband operation of ISM‐band applications
Authors: Yoon Cheol , Kim Woo‐Su , Jeong Gye‐Taek , Choi Sun‐Ho , Lee Hwa‐Choon , Park Hyo‐Dal 
Published: June 2012

AbstractThis article presents the design and fabrication of three ISM‐bands coplanar waveguide (CPW)‐fed patch antenna on a thin substrate for applications within 2.400–2.484, 5.150–5.350, and 5.725–5.825 GHz bandwidths. The prototype consists of a thin substrate and a CPW‐fed patch. To obtain sufficient bandwidth with −10 dB return loss, a thin substrate layer is inserted under the ground plate and the radiator. A thin substrate CPW‐fed patch that has three ISM‐bands is used. Important design parameters are the radiator's construction, width, length, the substrate height, and the CPW‐fed gaps. From these optimized parameters, a CPW‐fed patch antenna is fabricated and measured. The measured results of the fabricated antenna are obtained from operating bands at 4.23‐GHz bandwidths with a −10 dB return loss referenced to the center frequency, and the peak gain at 3.82 dBi. The experimental radiation efficiency in both the E‐plane and H‐plane is shown to be a pass band total of 50–82%. It is capable of covering three ISM bands at 2.400–2.484 and 5.150–5.350/5.725–5.825 GHz, which is ideally suitable for short‐range wireless applications. © 2012 Wiley Periodicals, Inc. Microwave Opt Technol Lett 54:2199–2202, 2012; View this article online at wileyonlinelibrary.com.). DOI 10.1002/mop.26994
Novel dual‐mode patch band‐pass filters with slot structures
Authors: La Dong‐sheng , Ma Xue‐lian , Chen Haiyan , Wu Ya‐ping 
Published: June 2012

AbstractTwo novel microstrip band‐pass filters using dual‐mode patch resonators with slot structures are proposed and optimized in this article. By using etched slot defected structures in the circle patch resonator and the regular hexagon patch resonator, the filters have remarkable advantages, such as compact size, high selectivity, and simple structure. The proposed band‐pass filters are simulated, fabricated, and measured. Each of the band‐pass filters has two transmission zeros. The measured results prove to be largely consistent with the simulated results. © 2012 Wiley Periodicals, Inc. Microwave Opt Technol Lett 54:2130–2133, 2012; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.27002
Dielectric probes for submillimeter and terahertz‐wave range instrumentation and characterizations
Authors: Bayat Khadijeh , Chaudhuri Sujeet K. , Safavi‐Naeini Safieddin 
Published: June 2012

AbstractIn this letter, a new set of silicon probes, at submillimeter and terahertz frequency range, for I/O connectivity and instrumentation applications are introduced.The designed probes are optimized for testing of planar silicon‐based integrated circuits using newly introduced network analyzers, e.g., a PNA‐X. The probes have been optimized for different frequency windows matched to the standard metallic rectangular waveguides (WR‐2, WR‐4, and WR‐6) corresponding to the frequency band of 110–500 GHz and higher. The probes comprised of highly resistive silicon channel waveguides, which are tapered on both sides laterally and vertically. The side of the probes which is coupled to the WR waveguide is tapered laterally and the other end which is used to couple the signal to or out of the sample under the test is tapered vertically with an angle of 54.6°. The probes are pressed (side‐coupled) on the sample under the test. The probing system consisting of the input and output tapers and a channel silicon waveguide as the sample under the test are designed and simulated using HFSS v.12 for three windows of frequencies including 110–170, 170–260, and 325–500 GHz. The simulation results show that the insertion loss and return loss are lower than 3 dB and higher than 15 dB, respectively; which are much better than the losses of commercially available high frequency probes. © 2012 Wiley Periodicals, Inc. Microwave Opt Technol Lett 54:2095–2098, 2012; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.27003
Scalable optical serial to parallel converter based on prechirped pulse probe and cross‐phase modulation in fiber
Authors: Yu Jinlong , Luo Jun , Wang Wenrui , Guo Jingzhong , Yang Enze 
Published: June 2012

AbstractWe proposed and demonstrated 40–4 × 10 Gb/s optical serial to parallel converter based on the prechirped pulse probe and the fiber cross‐phase modulation‐based optical gate. We further show the potential to extend the demonstrated scheme to larger than 8 parallelization scale. © 2012 Wiley Periodicals, Inc. Microwave Opt Technol Lett 54:2108–2110, 2012; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.27006
Broadband series‐fed two dipole array antenna with an integrated balun for mobile communication applications
Authors: Yeo Junho , Lee Jong‐Ig 
Published: June 2012

AbstractA broadband series‐fed two dipole array antenna is presented for mobile‐base station applications covering the frequency bands for 2G, 3G, and long‐term evolution systems.Two printed‐strip dipole antennas with different lengths backed by a ground reflector are connected through a coplanar stripline, and an integrated balun consisting of a microstrip line and slot line is used to match the input impedance of the antenna to the 50 Ω feed line. Experimental results show that for a voltage standing wave ratio < 2, the proposed antenna presents a 49% bandwidth in the range of 1.7–2.8 GHz, a stable gain of 5.5–6.3 dBi, and a front‐to‐back ratio of 12–17 dB. Thus, the proposed antenna is suitable as a broadband base station element antenna, covering all mobile frequency bands. © 2012 Wiley Periodicals, Inc. Microwave Opt Technol Lett 54:2166–2168, 2012; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.27009
Circularly polarized slot antenna design and analysis using magnetic current distribution for rfid reader applications
Authors: Chen Hua‐Ming , Chiu Kuo‐Yung , Lin Yi‐Fang , Yeh Shu‐An 
Published: June 2012

AbstractA microstrip‐to‐slotline transition technique is presented, for the coupling of a circularly polarized circular slot antenna in the ultrahigh frequency band.The fundamental TE11 mode of the circular slot antenna is investigated, using the magnetic current flow in the slot. In the proposed design, circular polarization (CP) is generated using a proper c‐strip metal, within the circular slot structure, and connecting a strip metal to the circular slot edge, at −45° to the feeding slotline. The direct slotline feed is coupled to a 50‐Ω microstrip line, on the opposite side of the substrate. Simulated and measured results indicate that the proposed structure achieves good CP radiation, in the TE11 mode. The impedance bandwidth and the 3‐dB axial‐ratio bandwidth for the design are approximately 22.1% and 2.5%, respectively. © 2012 Wiley Periodicals, Inc. Microwave Opt Technol Lett 54:2016–2023, 2012; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.27013
Novel dual‐band RFID antenna configuration with independent tuning adjustment
Authors: Grilo M. , Arnold F. J. , Gonçalves M. S. , Bravo‐Roger L. L. , Moretti A. , Lima I. T. 
Published: June 2012

AbstractWe propose a novel dual‐band radio frequency identification (RFID) microstrip antenna that has a similar performance in dual bands that can be independently tuned. The return loss of the dual‐band antenna is less than −10 dB between 890 and 965 MHz and 2.33 and 2.51 GHz. The simplicity of this microstrip dual band antenna layout makes it particularly suitable for low‐cost RFID production. © 2012 Wiley Periodicals, Inc. Microwave Opt Technol Lett 54:2214–2217, 2012; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.27025
Influence of device dimension and gate recess on the characteristics of AlGaN/GaN high electron mobility transistors
Authors: Lee Jong‐Min , Yoon Hyung‐Sup , Min Byoung‐Gue , Mun Jae‐Kyoung , Nam Eunsoo 
Published: June 2012

AbstractIn this article, a gate recessed AlGaN/GaN high electron mobility transistor (HEMT) was developed using 4‐in. compound semiconductor process. We designed and fabricated four types of AlGaN/GaN HEMT to characterize the performance of devices. The effects of the gate recess depth and the device dimension of AlGaN/GaN HEMT are demonstrated. We present the scaling effect of the source‐gate and the drain‐gate enhancing the drain current and the transconductance. In addition, the current collapse was measured to estimate the trap effect in the surface and the buffer layer. Moreover, the comparison of RF performance of HEMT with different structure designs was performed. Based on these results, the optimization and the improvement of gate recessed GaN devices can be defined. © 2012 Wiley Periodicals, Inc. Microwave Opt Technol Lett 54:2103–2106, 2012; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.27036
Temperature influence on polarization effects in optical fibers
Authors: Bessa dos Santos A. , Borghi G. , de Faria G. Vilela 
Published: June 2012

AbstractThe differential group delay (DGD) behavior of single‐mode optical fibers was analyzed with regards to temperature variation. It was observed that the DGD curve shape along the wavelength axis could change if the fiber was submitted to high‐temperature values. The study was carried out under laboratory conditions. © 2012 Wiley Periodicals, Inc. Microwave Opt Technol Lett 54:2070–2074, 2012; View this article online at wileyonlinelibrary.com.). DOI 10.1002/mop.27038
The Impact of Appearance Concerns on Depression and Anxiety in Rheumatoid Arthritis
Authors: McBain Hayley , Shipley Michael , Newman Stanton ,   members of the Appearance Research Collaboration (ARC)
Published: June 2012

AbstractObjectivesIncreased levels of anxiety and depression are commonly reported by patients with rheumatoid arthritis (RA) in comparison to the general population. Rather than the clinical features of the disease, this difference has been attributed to psychosocial factors. Patients with RA can develop joint swelling and disfigurement as a direct result of the disease, and experience concerns about their altered appearance. This study aimed to identify if appearance‐specific issues contribute to our understanding of mood in RA, over and above demographic, functional and generalized psychosocial measures.MethodsA total of 89 patients with RA completed a series of psychosocial questionnaires measuring demographics, physical function, general cognitive processes and a number of appearance‐specific concepts, to determine the contribution of appearance concerns to mood.ResultsHierarchical linear regression suggested that living status, optimism, social support and appearance‐related social anxiety and avoidance are associated with levels of depression. The relationship between social support and depression was found to be mediated by appearance‐related social anxiety and avoidance. Optimism remained the only variable significantly associated with anxiety.ConclusionThese findings confirm the role of optimistic cognitions and a supportive environment in determining the mood of patients with RA and also establishes a possible link between depression and appearance concerns in this population. Interventions targeting social support, optimism and social anxiety and avoidance in relation to appearance are key in the improvement of depression in this patient group. Copyright © 2012 John Wiley & Sons, Ltd.
Electrophysiological subtypes and prognosis of Guillain–Barré syndrome in Northeastern China
Authors: Ye Yuqin , Wang Keren , Deng Fang , Xing Yingqi 
Published: June 2012

AbstractIntroduction:The purpose of this study was to assess the electrophysiological subtypes and prognosis of Guillain–Barré syndrome (GBS) in northeastern China.Methods:Ninety‐nine patients with GBS were recruited between 2006 and 2010 and retrospectively reviewed.Results:Sixty‐seven percent of patients had acute inflammatory demyelinating polyneuropathy (AIDP). Patients with acute motor axonal neuropathy (AMAN) had more severe symptoms at onset of GBS, and intravenous immunoglobulin (IVIg) was less effective in these patients. The prognosis may have been associated with the severity of the illness and did not differ between AMAN and AIDP patients. Abnormal motor nerve conduction studies (NCS) of the lower limbs and sensory NCS of the upper limbs with normal sural sensory nerve studies were the main electrophysiological features of AIDP.Conclusions:AIDP is the main subtype of GBS, and it has specific electrophysiological characteristics in northeastern China. The prognosis of patients with AMAN was similar to that of patients with AIDP. Moreover, IVIg was more effective in patients with AIDP. Muscle Nerve, 2013
Fatigue and daytime sleepiness scale in myotonic dystrophy type 1
Authors: Hermans Mieke C.E. , Merkies Ingemar S.J. , Laberge Luc , Blom Eveline W. , Tennant Alan , Faber Catharina G. 
Published: June 2012

AbstractIntroduction: Fatigue and excessive daytime sleepiness are frequent complaints in myotonic dystrophy type 1 (DM1) that often overlap. We aimed to construct a combined fatigue and daytime sleepiness rating scale for DM1 using the Rasch measurement model. Methods: Questionnaires, including the Epworth Sleepiness Scale, Fatigue Severity Scale, and Daytime Sleepiness Scale, were completed by 354 patients. Data were subjected to Rasch analyses and tested for required measurement issues such as appropriate response categories, absence of item bias, local independence, and unidimensionality. Results: The initial 22 items did not meet Rasch model expectations. After rescoring and removing misfitting items, the final 12‐item scale showed good model fit and unidimensionality. High internal consistency (person separation index = 0.80) and validity were demonstrated. Conclusions: The Rasch‐built Fatigue and Daytime Sleepiness Scale, developed specifically for DM1 patients, provides interval measures on a single continuum. Its use is suggested for future clinical trials and therapeutic follow‐up. Muscle Nerve, 2013
An invariant subspace‐based approach to the random eigenvalue problem of systems with clustered spectrum
Authors: Ghosh Debraj , Ghanem Roger 
Published: June 2012

SUMMARYThe repeated or closely spaced eigenvalues and corresponding eigenvectors of a matrix are usually very sensitive to a perturbation of the matrix, which makes capturing the behavior of these eigenpairs very difficult. Similar difficulty is encountered in solving the random eigenvalue problem when a matrix with random elements has a set of clustered eigenvalues in its mean. In addition, the methods to solve the random eigenvalue problem often differ in characterizing the problem, which leads to different interpretations of the solution. Thus, the solutions obtained from different methods become mathematically incomparable. These two issues, the difficulty of solving and the non‐unique characterization, are addressed here. A different approach is used where instead of tracking a few individual eigenpairs, the corresponding invariant subspace is tracked. The spectral stochastic finite element method is used for analysis, where the polynomial chaos expansion is used to represent the random eigenvalues and eigenvectors. However, the main concept of tracking the invariant subspace remains mostly independent of any such representation. The approach is successfully implemented in response prediction of a system with repeated natural frequencies. It is found that tracking only an invariant subspace could be sufficient to build a modal‐based reduced‐order model of the system. Copyright © 2012 John Wiley & Sons, Ltd.