bluuebunny/crossref_metadata_2025 huggingface dataset:
Land cover change and its relation with population dynamics in Burkina Faso, West Africa
Authors: Ouedraogo I. , Tigabu M. , Savadogo P. , Compaoré H. , Odén P. C. , Ouadba J. M.
Published: March 2010

In the tropics, conversion of woodland and forest into cropland and pasture has risen drastically during the last decade. Rapid population growth and poverty are believed to be the main factors of change in land use in these zones. Southern Burkina Faso experienced rapid population growth due to massive peasants' migration from the north and central regions of the Country, exacerbated by decreasing rainfall and arable land in the area of origin. This paper assessed the impact of such increased population on land use change in the attracting zones from 1986 to 2006. Satellite images were used to measure changes in land cover types over time and national population census data were used to examine the population dynamics over the same time. Results showed that the forest land was progressively converted to croplands at an annualized rate of 0·96 per cent, while the population density shifted from 17 inhabitants per km2 in 1986 to 30 inhabitants per km2 in 2006. Pearson correlation analysis revealed the positive role of population size and distribution in explaining land cover change. Policy initiatives that will lead to better environmental management are recommended. Copyright © 2010 John Wiley & Sons, Ltd.
Effect of GroEL on Thermal Aggregation of Glycogen Phosphorylase b from Rabbit Skeletal Muscle
Authors: Eronina Tatyana B. , Chebotareva Natalia A. , Bazhina Svetlana G. , Kleymenov Sergey Y. , Naletova Irina N. , Muronetz Vladimir I. , Kurganov Boris I.
Published: March 2010

The suppression of the thermal aggregation of glycogen phosphorylase b (Phb) from rabbit skeletal muscle by the chaperonin GroEL is studied using dynamic light scattering. It is shown that the decrease in the rate of Phb aggregation under the action of GroEL is due to the transition of the aggregation process from the kinetic regime, wherein the rate of aggregation is limited by diffusion of the interacting particles, to a regime where the sticking probability for the colliding particles becomes lower than one (reaction‐limited cluster‐cluster aggregation). The analytical‐ultracentrifugation data show that elevated temperatures induce dissociation of the dimeric Phb. The formation of a complex between the denatured monomeric form of Phb and the dissociated forms of GroEL is detected during heating at 46 °C.

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Response of Human Corneal Fibroblasts on Silk Film Surface Patterns
Authors: Gil Eun Seok , Park Sang‐Hyug , Marchant Jeff , Omenetto Fiorenzo , Kaplan David L.
Published: March 2010

Transparent, biodegradable, mechanically robust, and surface‐patterned silk films were evaluated for the effect of surface morphology on human corneal fibroblast (hCF) cell proliferation, orientation, and ECM deposition and alignment. A series of dimensionally different surface groove patterns were prepared from optically graded glass substrates followed by casting poly(dimethylsiloxane) (PDMS) replica molds. The features on the patterned silk films showed an array of asymmetric triangles and displayed 37–342 nm depths and 445–3 582 nm widths. hCF DNA content on all patterned films were not significantly different from that on flat silk films after 4 d in culture. However, the depth and width of the grooves influenced cell alignment, while the depth differences affected cell orientation; overall, deeper and narrower grooves induced more hCF orientation. Over 14 d in culture, cell layers and actin filament organization demonstrated that confluent hCFs and their cytoskeletal filaments were oriented along the direction of the silk film patterned groove axis. Collagen type V and proteoglycans (decorin and biglycan), important markers of corneal stromal tissue, were highly expressed with alignment. Understanding corneal stromal fibroblast responses to surface features on a protein‐based biomaterial applicable in vivo for corneal repair potential suggests options to improve corneal tissue mimics. Further, the approaches provide fundamental biomaterial designs useful for bioengineering oriented tissue layers, an endemic feature in most biological tissue structures that lead to critical tissue functions.

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The Dirichlet problem for second order parabolic operators in non‐cylindrical domains
Authors: Argiolas Roberto , Grimaldi Anna Piro
Published: March 2010

In this paper we develope a perturbation theory for second order parabolic operators in non‐divergence form. In particular we study the solvability of the Dirichlet problem in non cylindrical domains with Lp ‐data on the parabolic boundary (© 2010 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Propagation of singularities for Cauchy problems of semilinear thermoelastic systems with microtemperatures
Authors: Yang Lin , Huang Lihong
Published: March 2010

The propagation of singularities of solutions to the Cauchy problem of a semilinear thermoelastic system with microtemperatures in one space variable is studied. First, by using a diagonalization argument of phase space analysis, the coupled thermoelastic system with microtemperatures will be decoupled microlocally. Second, using a classical bootstrap argument, the property of finite propagation speed of singularities for the semilinear thermoelastic system is obtained. Finally, it is also shown that the microlocal weak singularities propagate along the null bicharacteristics of the hyperbolic operators of the coupled semilinear system (© 2010 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Some new characterizations on spaces of functions with bounded mean oscillation
Authors: Yang Dachun , Zhou Yuan
Published: March 2010

Let X be a space of homogeneous type. The authors introduce some generalized approximations to the identity (for short, GAI) with optimal decay conditions in the sense that these conditions are the sufficient and necessary conditions for these GAI's to characterize BMO(X), the space of functions with bounded mean oscillation on X. The authors also obtain a new John‐Nirenberg‐type inequality associated with GAI's, which leads some new characterizations of BMO(X) in terms of rearrangement functions, and certain maximal functions related to GAI's. Some variants of these characterizations for BMO‐type spaces on X of Duong and Yan are also established. Moreover, the equivalence between BMO and the space of BMO type on Ahlfors n ‐regular quasimetric measure spaces is obtained, which confirms an assertion of Duong and Yan (© 2010 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
The asymptotic zero distribution of sections and tails of classical Lindelöf functions
Authors: Ostrovskii Iossif , Zheltukhina Natalya
Published: March 2010

We study the asymptotic (as n → ∞) zero distribution of
In (z, μ, Γλ) = (1 ‐ μ)sn (z, Γλ) ‐ μtn +1(z, Γλ),
where μ ∈ ℂ, sn is nth section, tn is nth tail of the power series of classical Lindelöf function Γλ of order λ. Our results generalize the results by A. Edrei, E. B. Saff, and R. S. Varga for the case μ = 0 (© 2010 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Bilinear isometries on subspaces of continuous functions
Authors: Font Juan J. , Sanchis M.
Published: March 2010

Let A and B be strongly separating linear subspaces of C0(X) and C0(Y), respectively, and assume that ∂A ≠ ∅︁ (∂A stands for the set of generalized peak points for A) and ∂B ≠ ∅︁. Let T: A × B → C0(Z) be a bilinear isometry. Then there exist a nonempty subset Z0 of Z, a surjective continuous mapping h: Z0 → ∂A × ∂B and a norm‐one continuous function a: Z0 → K such that T (f, g)(z) = a (z)f (πx (h (z))g (πy (h (z)) for all z ∈ Z0 and every pair (f, g) ∈ A × B. These results can be applied, for example, to non‐unital function algebras (© 2010 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Heterogeneous “Organoclick” Derivatization of Polysaccharides: Photochemical Thiol‐ene Click Modification of Solid Cellulose
Authors: Zhao Gui‐Ling , Hafrén Jonas , Deiana Luca , Córdova Armando
Published: March 2010

A simple and direct method for derivatization of solid polysaccharides is presented. The novel methodology is based on the combination of organic acid‐catalyzed esterification or etherification and photochemical thiol‐ene click derivatization of a heterogeneous polysaccharide. The solid cellulose was “organoclick” modified with aryl, alkyl and polyester groups, respectively. The modification allows for a highly modular and metal free surface modification of solid polysaccharides.

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Shape‐Persistent, Truxene‐Based, Nano‐Sized Bisterpyridine Ruthenium(II) Complexes: Synthesis and Photophysical Properties
Authors: Wang Jin‐Liang , Chan Yi‐Tsu , Moorefield Charles N. , Pei Jian , Modarelli David A. , Romano Natalie C. , Newkome George R.
Published: March 2010

A new series of shape‐persistent metallomacromolecules G0 and G1 as well as corresponding ligands, based on thiophene‐functionalized bisterpyridine‐Ru(II) with truxene moieties, as the nodes, were developed. All new compounds were fully characterized by 1H, COSY, and 13C NMR, as well as MALDI‐TOF MS. Their photophysical properties revealed that the branched scaffold resulted in high molar absorption coefficients and broad absorption making these materials potential candidates for light‐harvesting.

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Dual Emission from Highly Conjugated 2,2′:6′:2″‐Terpyridine Complexes—A Potential Route to White Emitters
Authors: Siebert Ronald , Winter Andreas , Dietzek Benjamin , Schubert Ulrich S. , Popp Jürgen
Published: March 2010

Here, we present a new class of terpyridine complexes of the transition‐metal ions, iron(II), ruthenium(II), and osmium(II), overcoming the poor emission properties typical for this class of polypyridyl complexes. These complexes show, besides an increased room‐temperature emission quantum yield and a prolonged lifetime of the metal‐to‐ligand charge‐transfer (MLCT) states, dual emission from two well‐separated excited states of the same molecule. These experimental findings are attributed to a highly stabilized ligand chromophore, where photoinduced excited‐state planarization causes an enhancement of electron delocalization. This planarization, in turn, reduces the potential energy of the S1 state and minimizes electronic coupling to the MLCT state, which is prone to non‐radiative deactivation via metal‐centered excited states. Due to their dual emission the complexes presented here show emission covering the entire Vis spectral range upon excitation of the ππ* states in the near UV. Thus, by structurally tuning the electronic coupling of the ππ* and the MLCT states a new synthetic route toward white emitters, which can subsequently be incorporated into polymers, is opened.

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Returning to Basics: Direct Integration of the Full Molecular‐Weight Distribution Equations in Addition Polymerization
Authors: Saldívar‐Guerra Enrique , Infante‐Martínez Ramiro , Vivaldo‐Lima Eduardo , Flores‐Tlacuahuac Antonio
Published: March 2010

Direct integration of the equations describing the full MWD in addition polymerization is shown to be feasible in reasonable computing times using standard computers for a considerable number of realistic systems. This is possible if the stiffness of the system is removed (if present) by the application of the QSSA, and the use of suitable numerical methods. This communication provides the basic ideas of a general method, based on the chemical nature of the system and the structure of the MWD equations. The application of the method provides additional insight on the dynamics and the underlying chemistry of the system. Examples of free radical polymerizations including controlled radical polymerization are offered, which can be solved in less than an hour on a PC.

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Reverse lateral supramalleolar adipofascial flap and skin grafting for one‐stage soft tissue reconstruction of foot and ankle joint
Authors: Lee Jae‐Hoon , Chung Duke‐Whan
Published: March 2010

The aim of this report is to present the clinical result and efficacy of reverse lateral supramalleolar adipofascial flap and skin grafting for one stage soft tissue reconstruction of the foot and ankle joints. Reconstruction using a reverse lateral supramalleolar adipofascial flap and skin grafting was performed in eight cases between January 2005 and March 2009. All the subjects were male with a mean age of 53 years. The mean follow‐up period was 20 months. The reasons for soft tissue defects were diabetic foot, infected bursitis, open injuries of the foot, and chronic osteomyelitis. The mean size of the flaps was 3.5 (3–4) × 4.5 (4–6) cm. The flaps were elevated in the form of an adipofascial flap and split‐thickness skin grafting was performed over the flaps and adjoining raw areas. Flaps survived in all cases. The implantation of the split‐thickness skin graft over the flap was also successful in all cases. Neither partial necrosis in the adipofascial flap nor venous congestion was observed. At the last follow‐up, there were no limited motions in the ankle and the toe. No cases complained of inconveniences in ambulation or had difficulties in selecting footwear. In cases that require a flap for the exposed bone or tendon of the foot with a small‐sized defect, reverse lateral supramalleolar adipofascial flap and skin grafting is considered a useful method as it lowers the morbidity rate of the donor site and reconstructs soft tissues. © 2010 Wiley‐Liss, Inc. Microsurgery 30:423–429, 2010.
Bioabsorbable device for small‐caliber vessel anastomosis
Authors: Ueda Kazunori , Mukai Tomokazu , Ichinose Shizuko , Koyama Yoshihisa , Takakuda Kazuo
Published: March 2010

Although the devices for large‐caliber vessel (>2‐mm diameter) anastomosis are available, there are no devices for performing anastomosis of small‐caliber vessels. We designed a hooked device composed of a bioabsorbable polymer for sutureless anastomosis of small‐caliber vessels. The efficacy of this device was evaluated by in vitro degradation and arterial‐fixation strength tests as well as in vivo transplantation experiments with common carotid arteries of growing SD rats. A nonabsorbable device without hooks served as the control in the fixation strength and animal experiments. The tensile strength of the bioabsorbable device decreased to 27 and 9% of the initial value after 8‐ and 24‐week incubation, respectively. The fixation strength was greater and the anastomotic time was shorter with this device than with the control. The transplantation experiments showed complete endothelial bridging in both devices at 2 weeks after surgery (n = 6). The control device created a considerable protrusion into the arterial lumen at 8 postoperative weeks, whereas the experimental device did not (n = 6). Arterial diameter measurements detected a significant difference between the inner diameters at the respective anastomotic sites (n = 6, P < 0.05) and demonstrated that the control device hindered the vessel growth while the experimental device did not. Therefore, the bioabsorbable hooked device was an effective tool for anastomosis of small‐caliber arteries (ca. 1‐mm diameter). © 2010 Wiley‐Liss, Inc. Microsurgery 30:494–501, 2010.
Sticky platelet syndrome as a possible cause for free flap failure—A case report
Authors: Loeffelbein Denys John , Baumann Claudia Maria , Mücke Thomas , Wolff Klaus‐Dietrich , Hölzle Frank , Kesting Marco Rainer
Published: March 2010

We report a case of a patient who developed clinical symptoms of sticky platelet syndrome (SPS) during free microvascular flap transplantation, following resection of an oral tumor. Multiple arterial thromboses of two free tissue transfers occurred as a probable result of SPS. Diagnosis and treatment of the various forms of SPS are described. © 2010 Wiley‐Liss, Inc. Microsurgery 30:466–468, 2010.
Arterialized venous flaps: A review of the literature
Authors: Yan Hede , Brooks Darrell , Ladner Raven , Jackson William D. , Gao Weiyang , Angel Michael F.
Published: March 2010

The arterialized venous flaps are highly regarded in microsurgical and reconstructive surgeries based on advantages of ease of design and harvest without the need to perform deep dissection, no sacrifice of a major artery at the donor site, no limitation of the donor sites, and less donor‐site morbidity. Many experimental investigations and clinical applications have been reported. However, their survivals are still inconsistent, and survival mechanisms remain controversial. In this review, we update the existing problems, experimental studies for survival mechanisms, clinical practices, and methods developed to improve their survivals. © 2010 Wiley‐Liss, Inc. Microsurgery 30:472–478, 2010.
Chromium dinicocysteinate supplementation can lower blood glucose, CRP, MCP‐1, ICAM‐1, creatinine, apparently mediated by elevated blood vitamin C and adiponectin and inhibition of NFκB, Akt, and Glut‐2 in livers of zucker diabetic fatty rats
Authors: Jain Sushil K. , Croad Jennifer L. , Velusamy Thirunavukkarasu , Rains Justin L. , Bull Rebeca
Published: March 2010

Chromium and cysteine supplementation can improve glucose metabolism in animal studies. This study examined the hypothesis that a cysteinate complex of chromium is significantly beneficial than either of them in lowering blood glucose and vascular inflammation markers in Zucker diabetic fatty (ZDF) rats. Starting at the age of 6 wk, ZDF rats were supplemented orally (daily gavages for 8 more weeks) with saline‐placebo (D) or chromium (400 μg Cr/Kg body weight) as chromium dinicocysteinate (CDNC), chromium dinicotinate (CDN) or chromium picolinate (CP) or equimolar L‐cysteine (LC, img/Kg body weight), and fed Purina 5008 diet for 8 wk. ZDF rats of 6 wk age before any supplementations and onset of diabetes were considered as baseline. D rats showed elevated levels of fasting blood glucose, HbA1, CRP, MCP‐1, ICAM‐1 and oxidative stress (lipid peroxidation) and lower adiponectin and vitamin C, when compared with baseline rats. In comparison to D group, CDNC group had significantly lower blood glucose, HbA1, CRP, MCP‐1, ICAM‐1 and lipid peroxidation and increased vitamin C and adiponectin levels. CDN, CP or LC showed significantly less or no effect on these biomarkers. Only CDNC lowered blood creatinine levels in comparison to D. While CDN and CP had no effect, activation of NFκB, Akt and glucose transporter‐2 levels were decreased, insulin receptor substrate 1 (IRS‐1) activation increased in livers of CDNC‐rats. CDNC effect on glycemia, NFκB, Akt and IRS‐1 in liver was significantly greater compared with LC. Blood chromium levels did not differ between Cr‐groups. Exogenous vitamin C supplementation significantly inhibited MCP‐1 secretion in U937 monocytes cultured in high‐glucose‐medium. CDNC is a potent hypoglycemic compound with anti‐inflammatory activity apparently mediated by elevated blood vitamin C and adiponectin and inhibition of NFκB, Akt, and Glut‐2 and increased IRS‐1 activation in livers of type 2 diabetic rats.
Sesamin attenuates intercellular cell adhesion molecule‐1 expression in vitro in TNF‐α‐treated human aortic endothelial cells and in vivo in apolipoprotein‐E‐deficient mice
Authors: Wu Wen‐Huey , Wang Shu‐Huei , Kuan I‐I , Kao Ya‐shi , Wu Pei‐Jhen , Liang Chan‐Jung , Chien Hsiung‐Fei , Kao Chiu‐Hua , Huang Ching‐Jang , Chen Yuh‐Lien
Published: March 2010

Sesame lignans have antioxidative and anti‐inflammatory properties. We focused on the effects of the lignans sesamin and sesamol on the expression of endothelial‐leukocyte adhesion molecules in tumor necrosis factor‐α (TNF‐α)‐treated human aortic endothelial cells (HAECs). When HAECs were pretreated with sesamin (10 or 100 μM), the TNF‐α‐induced expression of intercellular cell adhesion molecule‐1 (ICAM‐1) was significantly reduced (35 or 70% decrease, respectively) by Western blotting. Sesamol was less effective at inhibiting ICAM‐1 expression (30% decrease at 100 μM). Sesamin and sesamol reduced the marked TNF‐α‐induced increase in human antigen R (HuR) translocation and the interaction between HuR and the 3'UTR of ICAM‐1 mRNA. Both significantly reduced the binding of monocytes to TNF‐α‐stimulated HAECs. Sesamin significantly attenuated TNF‐α‐induced ICAM‐1 expression and cell adhesion by downregulation of extracellular signal‐regulated kinase 1/2 and p38. Furthermore, in vivo, sesamin attenuated intimal thickening and ICAM‐1 expression seen in aortas of apolipoprotein‐E‐deficient mice. Taken together, these data suggest that sesamin inhibits TNF‐α‐induced extracellular signal‐regulated kinase/p38 phosphorylation, nuclear translocation of NF‐κB p65, cytoplasmic translocalization of HuR and thereby suppresses ICAM‐1 expression, resulting in reduced adhesion of leukocytes. These results also suggest that sesamin may prevent the development of atherosclerosis and inflammatory responses.
Vitamin D‐mediated calcium absorption in patients with clinically stable Crohn's disease: A pilot study
Authors: Kumari Meena , Khazai Natasha B. , Ziegler Thomas R. , Nanes Mark S. , Abrams Steven A. , Tangpricha Vin
Published: March 2010

Vitamin D is the critical hormone for intestinal absorption of calcium. Optimal calcium absorption is important for proper mineralization of bone in the prevention of osteoporosis and osteoporotic fractures, among other important functions. Diseases associated with gut inflammation, such as Crohn's disease (CD), may impair calcium absorption. This pilot study evaluated vitamin D‐ dependent calcium absorption in subjects with CD. Male subjects with CD (n=4) and healthy age‐matched controls (n=5) were studied. All subjects had fractional calcium absorption (FCA; by the dual calcium isotope method), serum 25‐hydroxyvitamin D, serum calcium and 24 h urinary calcium excretion measurements at baseline. The FCA in response to vitamin D therapy was re‐assessed following administration of oral calcitriol 0.25 mcg twice daily for 1 wk, followed by oral calcitriol 0.50 mcg twice daily for 1 wk. Serum calcium and 24 h urinary calcium determinations were re‐assessed after each increasing dose of calcitriol as safety measures. There was no significant difference in calcium FCA at baseline or after increasing doses of calcitriol between the CD and controls. FCA in the control and CD group was approximately 35% at baseline, which increased to 60% after calcitriol therapy. No subject developed hypercalcemia or hypercalciuria. Our results suggest that CD patients have a normal response to vitamin D in enhancing the efficacy of calcium absorption. This suggests that stable CD patients can follow calcium and vitamin D guidelines of non‐CD adults. Other factors independent of vitamin D status may impair intestinal calcium absorption in CD, including the degree and location of inflammation, presence of surgical resection and/or use of glucocorticoids.
Tocotrienols activity in MCF‐7 breast cancer cells: Involvement of ERβ signal transduction
Authors: Comitato Raffaella , Leoni Guido , Canali Raffaella , Ambra Roberto , Nesaretnam Kalanithi , Virgili Fabio
Published: March 2010

The term Vitamin E is utilized to describe eight molecules, subdivided into two groups, tocopherols and tocotrienols (TTs). It has been shown that specific TTs affect the growth of several lines of tumour cells, and that this activity is not shared by tocopherols. In agreement with these observations, a TTs‐rich fraction from palm oil (PTRF) was reported to inhibit proliferation and induce apoptosis in several cancer cells. However, the molecular mechanism involved in TTs activity is still unclear. We have recently proposed that TTs pro‐apoptotic activity involves estrogen receptor beta (ERβ) signalling. In this study, we report that, in MCF‐7 breast cancer cell, expressing both ERα and ERβ, PTRF treatment increases ERβ nuclear translocation, as demonstrated by immunofluorescence experiments and significantly inhibits ERα expression (−458.91‐fold of change) and complete disappearing of the protein from the nucleus. Moreover, PTRF treatment induces ER‐dependent genes expression (macrophage inhibitory cytokine‐1, early growth response‐1 and Cathepsin D) which is inhibited by the ER inhibitor, ICI 182.780, and induces DNA fragmentation. Finally, cDNA‐array experiments suggest that the activation of specific pathways in cells treated with γ‐TT with respect to α‐TT. Our data suggest a novel potential molecular mechanism for TTs activity.
Dietary phenolic acids attenuate multiple stages of protein glycation and high‐glucose‐stimulated proinflammatory IL‐1β activation by interfering with chromatin remodeling and transcription in monocytes
Authors: Wu Chi‐Hao , Yeh Chi‐Tai , Shih Ping‐Hsiao , Yen Gow‐Chin
Published: March 2010

This study examined the effects of dietary phenolic acids on individual stages of protein glycation and utilized monocyte cultures to assess whether these phytochemicals modulate the activation of proinflammatory cytokine under high glucose (HG, 15 mmol/L) conditions mimicking diabetes. In vitro glycation assays showed that a number of phenolic acids exerted inhibitory effects on the glycation reaction and its subsequent crosslinking. Phenolic acids, especially methoxyphenolic acids, prevented increase in both levels of the interleukin‐1β (IL‐1β) and oxidative stress caused by HG. The effect appeared to be mediated by modulation of the protein kinase C/nuclear factor‐κB axis. Chromatin immunoprecipitation demonstrated for the first time that HG increased the recruitment of nuclear factor‐κB p65 and CREB‐binding protein to the IL‐1β promoter. Interestingly, HG also increased histone acetylation and methylation within the IL‐1β promoter and decreased histone deacetylase activities in monocytes, thus facilitating chromatin remodeling and transcription. Such inappropriate inflammatory responses were found to be controlled effectively by treatment with methoxyphenolic compounds. In conclusion, this study suggests that phenolic acids could exert their anti‐inflammatory activities as antiglycation agents and as modifiers of signaling pathways. It provides evidence for a novel mechanism by which phenolics supplementation might have additional protective effects against diabetic complications.
Structure–affinity relationship of flavones on binding to serum albumins: Effect of hydroxyl groups on ring A
Authors: Xiao Jianbo , Cao Hui , Wang Yuanfeng , Yamamoto Koichiro , Wei Xinlin
Published: March 2010

Four flavones (flavone, 7‐hydroxyflavone, chrysin, and baicalein) sharing the same B‐ and C‐ring structure but a different numbers of hydroxyl groups on the A‐ring were studied for their affinities for BSA and HSA. The hydroxylation on ring A of flavones increased the binding constants (Ka) and the number of binding sites (n) between flavones and serum albumins. The affinities of 7‐hydroxyflavone for BSA and HSA were about 800 times and 40 times higher than that of flavone, respectively. It appears that the optimal number of hydroxyl groups introduced to the ring A of flavones is one. As more hydroxyl groups were introduced to positions at C‐5, C‐6, and/or C‐7 of flavones, the affinities for serum albumins decrease. The critical energy transfer distances (R0) between the hydroxylated flavones (1–3 OH on the ring A) and serum albumins decreased with the increasing affinities for serum albumins.
Experimental characterization of a planar transmission‐line transformer in multilayered high dielectric constant film structure
Authors: Demenicis Luciene S. , Conrado Luiz Fernando M. , Margulis Walter , Carvalho Maria Cristina R.
Published: March 2010

This article describes the complete experimental characterization of a 10‐mm long planar transmission‐line transformer (TLT) in a multilayered high dielectric constant film structure. The multilayered configuration was obtained by deposition of a high dielectric constant BaTiO3(BTO) film over the conductors printed on conventional alumina bulk substrates. A transformation impedance level from 50 to 10 Ω could be achieved with comfortable transversal dimensions using this TLT. Frequency and time domain experimental results have confirmed theoretical predictions for this wideband compact device. © 2010 Wiley Periodicals, Inc. Microwave Opt Technol Lett 52: 1337–1340, 2010; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.25154
Evaluation of the effect of channel add/drop impact on power transients on the performance of a 10‐GB/S DWDM transmission system with hybrid EDFA/Raman amplification
Authors: Neto B. , Ferreira J. M. , Wada N. , Pinto A. N. , André P. S.
Published: March 2010

We experimentally assess the impact of the transient effect in the bit error rate of a 30 km 10 × 10 Gb/s DWDM transmission system with hybrid amplification.For that purpose, the analyzed hybrid system is composed by a counter‐pumped Raman fiber amplifier followed by an Erbium doped fiber preamplifier. The results show that the channels adding and drooping have a significant impact on the signal quality, in the worst case scenario a 8‐dB power penalty was obtained. © 2010 Wiley Periodicals, Inc. Microwave Opt Technol Lett 52: 1225–1228, 2010; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.25155
A printed antenna with constant gain over a wide bandwidth for ultra‐wideband applications
Authors: Ranga Y. , Esselle Karu P. , Weily A.R. , Verma A. K.
Published: March 2010

A constant‐gain printed circular monopole antenna (PCMA) is presented that operates from 4 to 12 GHz. The gain of the PCMA is enhanced with the use of surface‐wave excited, proximity‐coupled (SW‐PC), conductor‐backed, twin‐slot radiators. A significant improvement in 2 and 3 dB peak gain bandwidth in the XY plane (θ = 90°) is achieved, and the peak measured gain of the antenna is nearly constant (5.5 dBi ± 1.5 dB) from 3 to 10 GHz. It has a very broad radiation pattern in the azimuth plane and a typical figure of eight pattern in the elevation plane. The antenna is also compact, robust, and easy to fabricate. © 2010 Wiley Periodicals, Inc. Microwave Opt Technol Lett 52: 1261–1264, 2010; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.25157
Insertion loss of lensed fiber collimator with larger gradient‐index lens diameter
Authors: Lin Yu‐Cheng
Published: March 2010

The insertion loss of lensed fiber collimator using gradient‐index fiber of 140‐μm diameter spliced to single‐mode fiber is investigated. The power transmission equation is applied for theoretical analysis of the insertion loss between a lensed fiber pair. Both numerical and experimental data are presented in axial and lateral displacement. The optimum coupling position 600 μm for 0.29‐pitch lensed fiber and the maximum working distance 1027 μm for 0.27‐pitch lensed fiber are demonstrated. © 2010 Wiley Periodicals, Inc. Microwave Opt Technol Lett 52: 1235–1238, 2010; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.25171
Synthesis of compact UWB bandpass filter with improved performances
Authors: Chen Chun‐Ping , Nihei Hiroshige , Ma Zhewang , Anada Tetsuo
Published: March 2010

This article presents a synthesis of the ultra‐wideband bandpass (UWB) filters consisting of two short‐circuited stubs combined with two stages of stepped impedance resonators (SIRs).The practical and theoretical transfer functions of the proposed UWB filters are derived. An example filter is firstly theoretically‐designed by the proposed synthesis procedure, then optimized by EM simulator, fabricated in microstrip line and finally characterized by a network analyzer. A good agreement between the theoretical and experimental results validates the proposed synthesis procedure successfully. In addition, the results of the designed filter show that the characteristics of the new filter is even better than those of a conventional filter composed of three‐stage of SIRs but without stubs. This means the proposed filters have compact sizes compared with the conventional ones. The designed filter also exhibits good characteristics of low insertion losses, quite sharp skirts, a flat group delay, deep attenuations in stopband (especially in lower one), and satisfies even FCC outdoor specifications. © 2010 Wiley Periodicals, Inc. Microwave Opt Technol Lett 52: 1268–1271, 2010; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.25172
Displacement sensing with two asymmetrical inclined fibers
Authors: Yang H. Z. , Harun S. W. , Ahmad H.
Published: March 2010

Fiber optic displacement sensor (FODS) with two asymmetrical inclined fibers is demonstrated using an intensity modulation technique. Compared to the sensor with two symmetrical inclined fibers, the sensitivities of proposed FODS are improved by 64.7%, 40.8%, and 31.8% at inclination angles of 10°, 20°, and 30°, respectively. The analysis also shows that the increment of inclination angle increases the output sensitivity but reduces the linear range of the sensor. Compared to the case of parallel fibers, sensitivity can be improved by 3.6, 8.5, and 16 times for inclination angles of 10°, 20°, and 30° respectively. However, the corresponding linear ranges are decreased by 67%, 55%, and 33% for inclination angles of 10°, 20°, and 30°, respectively. © 2010 Wiley Periodicals, Inc. Microwave Opt Technol Lett 52: 1271–1274, 2010; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.25173
Full‐duplex OFDM‐ROF architecture based on millimeter‐wave generated by optical phase modulator
Authors: Tao Yao , Chen Lin , Goto Satoshi
Published: March 2010

We proposed and experimentally demonstrate a bidirectional orthogonal frequency‐division multiplexing‐radio‐over‐fiber (OFDM‐ROF) system by using an optical phase modulator and a fiber Bragger gating (FBG) to generate millimeter‐wave.The downstream date is 2.5‐Gb/s OFDM signals and the downstream wavelength is reused without signal erasure. © 2010 Wiley Periodicals, Inc. Microwave Opt Technol Lett 52: 1335–1337, 2010; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.25175
Design of a novel elliptical monopole UWB antenna with dual band‐notched function
Authors: Niu Shu‐Fei , Gao Guo‐Ping , Li Ming , Hu Yan‐Sheng , Li Bo‐Nian
Published: March 2010

In this article, a novel compact elliptical monopole ultra‐wideband antenna with dual notched bands is proposed and investigated. The dual‐notched characteristic is realized by an elliptic arc‐shaped slot inserted in the elliptical monopole and a compact coplanar waveguide resonant cell in the feed line. The measured results show that the frequency band of VSWR ≤2 covers 3.1 to 10.6 GHz UWB band, while the notched frequency bands are 3.45–3.75 GHz which covers 3.5 GHz WIMAX and 5–6 GHz which covers 5.15–5.85 GHz WLAN band, and the two notched bands are separately achieved. The proposed antenna has a monopole‐like radiation patterns. Gain of the proposed antenna and transfer function study show that dual band‐notched characteristics achieved which conforms with the results of VSWR. © 2010 Wiley Periodicals, Inc. Microwave Opt Technol Lett 52: 1306–1310, 2010; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.25176
A new balance‐fed disc‐slit monopole antenna for modern wireless systems
Authors: Chiu Cheng‐Nan , Lin Ya‐Jing
Published: March 2010

This article proposes a novel balance‐fed disc‐slit monopole antenna for modern wireless systems.The compact antenna is realized by merging a single‐ended disc‐slit monopole antenna with a defected‐ground balun. The resulting antenna has the special merits of high immunity against electromagnetic interference from nearby circuits and less sensitivity to size variation of the corresponding ground plane. A prototype was created and examined, and the results obtained demonstrate the promising performance of the newly proposed antenna. © 2010 Wiley Periodicals, Inc. Microwave Opt Technol Lett 52: 1239–1240, 2010; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.25182
A novel tri‐band rat race coupler with T‐shape step impedance transformers
Authors: Chu Qing‐Xin , Lin Feng
Published: March 2010

A novel tri‐band 3‐dB rat race coupler operating at two arbitrary frequencies and their mean frequency is presented through replacing quarter‐wavelength impedance transformers in a conventional rat race coupler by T‐shape step impedance transformers, which can be equivalent to quarter‐wavelength impedance transformers at the three frequencies. Closed‐form design equations are derived. For verification, a microstrip tri‐band 3‐dB rat race coupler operating at 1.5/3.5/5.5 GHz is fabricated, aimed to cover the 1.5 GHz GPS band, and the 3.5/5.5 GHz WiMAX bands. Simulated and measured results are in good agreement. © 2010 Wiley Periodicals, Inc. Microwave Opt Technol Lett 52: 1240–1244, 2010; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.25186
Usage of an automated three‐stub water‐loaded impedance generator for RBF calibration of a waveguide ten‐port reflectometer
Authors: Monzó‐Cabrera Juan , Pedreño‐Molina Juan Luis , Lozano‐Guerrero Antonio José , Clemente‐Fernández Francisco Javier , Díaz‐Morcillo Alejandro
Published: March 2010

In this work, a waveguide impedance generator based on the use of three motor‐controlled metallic stubs, a monomode cavity loaded with water and PTFE cylinders is used to calibrate a waveguide ten‐port reflectometer.Radial basis function neural networks are used to learn the relationship between the actual reflection coefficient and the power detectors' output. Results indicate that this impedance generator can be successfully used to calibrate the ten‐port reflectometer. © 2010 Wiley Periodicals, Inc. Microwave Opt Technol Lett 52: 1274–1277, 2010; Published online in Wiley InterScience (www.interscience. wiley.com). DOI 10.1002/mop.25187
Analog predistortion linearization of Doherty power amplifiers using bandwidth reduction of error signal
Authors: Lee Yong‐Sub , Lee Mun‐Woo , Kam Sang‐Ho , Jeong Yoon‐Ha
Published: March 2010

This article represents analog predistortion linearization of Doherty power amplifier (DPA) using bandwidth reduction of error signal. To verify our methods, two DPAs are implemented using a push‐pull GaN HEMT and a push‐pull Si LDMOS at 2.14 GHz and tested using the memory‐compensated analog predistorter with transistor‐based error generators and three‐branch nonlinear paths. From the measured four‐carrier WCDMA results, the proposed analog predistortion DPAs show the significant linearity improvement. © 2010 Wiley Periodicals, Inc. Microwave Opt Technol Lett 52: 1313–1316, 2010; Published online in Wiley InterScience (www.interscience. wiley.com). DOI 10.1002/mop.25190
Bandwidth enhancement of internal WWAN antenna using an inductively coupled plate in the small‐size mobile phone
Authors: Chang Chih‐Hua , Wong Kin‐Lu
Published: March 2010

By adding a small inductively coupled plate of size 10 × 45 mm2 to the system ground plane of the mobile phone with a short length of 60 mm only, wide lower and upper bands of its internal WWAN antenna (a printed monopole slot antenna in this study) to respectively cover the GSM850/900 and GSM1800/1900/UMTS bands can be obtained. The coupled plate is connected and vertically oriented to the system ground plane through a 10‐nH chip inductor, which effectively causes the small coupled plate to resonate at about 925 MHz. A new resonant mode contributed by the coupled plate is hence provided to enhance the bandwidth of the antenna's lower band, which is quickly decreased with decreasing ground plane length of the mobile phone. With the coupled plate added to the ground plane of length 60 mm, the obtained lower‐band bandwidth is about the same as that of the internal WWAN antenna for the ground plane of length 105 mm and without the coupled plate. Further, the antenna's upper band for the short ground plane of length 60 mm can still have wide bandwidth for both the cases with and without the coupled plate. Detailed effects of the inductively coupled plate on the bandwidth enhancement of the internal WWAN antenna are analyzed. © 2010 Wiley Periodicals, Inc. Microwave Opt Technol Lett 52: 1247–1253, 2010; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.25196
CPW‐fed compact slot antenna for WLAN operation in a laptop computer
Authors: Naser‐Moghadasi M. , Sadeghi Fakhr R. , Danideh A.
Published: March 2010

A rectangular slot antenna fed by a coplanar waveguide is proposed for dual‐band operations.The measured −10 dB bandwidth for return loss is from 2.05 to 2.65 GHz and 5.1 to 5.4 GHz, covering all the 2.4/5.2 GHz WLAN bands. A multi‐feed 12‐element planar array was designed and simulated. It shows that the features of small size, uniplanar structure, good radiation characteristics, and small mutual coupling are promising for multi‐input multi‐output applications in laptops. © 2010 Wiley Periodicals, Inc. Microwave Opt Technol Lett 52: 1280–1282, 2010; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.25198
A novel versatile multiband rectangular patch antenna
Authors: Singh L. Lolit Kumar , Gupta Bhaskar , Sarkar Partha P. , Yoshitomi K. , Yasumoto K.
Published: March 2010

A novel simple single‐layer single‐feed asymmetric cross‐slot rectangular patch antenna with air dielectric (εr = 1) substrate providing hexa, penta, quad, and tri frequency bands operation is proposed and experimentally studied.The same antenna is giving hexa, penta, quad, and tri frequency bands of operation by changing the feed position only. The measured hexa frequency bands of operations are at 1.11, 1.89, 2.61, 3.12, 3.52, and 3.84 GHz. The measured penta frequency bands of operations are at 1.12, 1.89, 2.58, 3.49, and 3.82 GHz. The measured quad frequency bands of operations are at 1.47, 2.44, 3.49, and 3.85 GHz. The measured tri frequency bands of operations are at 1.92, 2.62, and 3.14 GHz. These values are in good agreement with simulation results. The measured radiation patterns at each measured frequency are also shown. © 2010 Wiley Periodicals, Inc. Microwave Opt Technol Lett 52: 1348–1353, 2010; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.25202
Novel printed CPW‐FED slot antenna for wireless applications
Authors: Shanmuganantham T. , Raghavan S.
Published: March 2010

A novel design of compact coplanar waveguide (CPW)‐fed slot antenna for wireless applications is presented. It can operate in the IEEE 802.11a frequency band from 5 GHz to 5.5 GHz. The antenna is designed on a RT/duroid 5880 substrate with a permittivity 2.22 and with the size of 18.8 mm × 12.3 mm × 3.175 mm. The antenna has a 5% voltage standing wave ratio (VSWR) (2.3:1) bandwidth around 5.24 GHz. The fundamental parameters of the antenna, such as impedance, return loss, VSWR, and polarization are obtained. All meets the acceptable antenna standards. Simulation tool, based on the method of moments (ZELAND IE3D version 12.0), has been used to analyze and optimize the antenna. © 2010 Wiley Periodicals, Inc. Microwave Opt Technol Lett 52: 1258–1261, 2010; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.25210
Polyimide core 3D rectangular micro coaxial transmission lines
Authors: Natarajan Saravana P. , Hoff Andrew M. , Weller Thomas M.
Published: March 2010

This article introduces a 20‐μm tall, 75‐μm wide rectangular polyimide core micro coaxial transmission line that can be realized using a simplified fabrication procedure. Measurements of a 4‐bend, meandered micro coaxial line demonstrate an 8% increase in the insertion loss and a 2% variation in the phase compared with a straight line of equivalent length. Cross‐coupling below 30 dB up to 65 GHz has been measured between two micro coaxial lines separated by 175 μm. These properties make the structures as useful building blocks for highly miniaturized and integrated microwave circuitry. © 2010 Wiley Periodicals, Inc. Microwave Opt Technol Lett 52: 1291–1293, 2010; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.25212
Q‐factor investigation of antennas over metamaterials substrates
Authors: Collardey S. , Sharaiha A. , Abdouni W. , Niamien C. , Tarot A.‐C.
Published: March 2010

In this article, antennas over metamaterials substrates are investigated with the radiatingQfactor determined by using a time‐domain method.The main objective is to illustrate the electromagnetic behavior of this kind of complex structure by calculating its energy budget (stored and radiated energies). An example of a patch antenna using such materials is analyzed and experimental results are presented. © 2010 Wiley Periodicals, Inc. Microwave Opt Technol Lett 52: 1321–1325, 2010; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.25213
A 5‐bit CMOS phase shifter with low phase and amplitude error using a new 180° phase shifter featuring process‐variation immunity
Authors: Kang Dong‐Woo , Hong Songcheol
Published: March 2010

In this letter, a high‐performance 5‐bit CMOS phase shifter using a newly proposed 180° bit is presented for a Ku‐band mobile satellite phased array receiver. The 180° phase shifter exhibits good tolerance to substrate parasitic capacitances when compared with a conventional high‐pass/low‐pass type one. The designed 5‐bit CMOS phase shifter demonstrates a typical 11.7 dB ± 0.5 dB insertion loss and a 2.1° rms phase shift error at 12.2 GHz. © 2010 Wiley Periodicals, Inc. Microwave Opt Technol Lett 52: 1325–1328, 2010; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.25214
1H and 13C NMR spectral data of bioactive cage‐like polycyclic compounds
Authors: Salles Roberta C. , Lacerda Valdemar , Beatriz Adilson , Ito Felicia M. , dos Santos Reginaldo B. , Greco, Sandro J. , de Castro Eustáquio V. R. , de Lima Dênis P.
Published: March 2010

Bioactive cage‐like polycyclic compounds have attracted the attention of several research groups because of their unique appearance and their biological activities. Their structures were established on the basis of 1H NMR and 13C NMR spectroscopic data. The 1H and 13C signal assignments and most homonuclear hydrogen coupling constants were assigned by use of techniques such as 1D 1H and 13C NMR and 2D gCOSY, non‐edited gHSQC and gHMBC. The gNOESY experiments proved the endo‐stereochemistry. Copyright © 2010 John Wiley & Sons, Ltd.
Mechanism and Kinetics of the Spontaneous Thermal Copolymerization of Styrene/Maleic Anhydride. Experimental and Simulation Studies in the Presence of 4‐oxo‐TEMPO
Authors: Mota‐Morales Josué D. , Quintero‐Ortega Iraís , Saldívar‐Guerra Enrique , Luna‐Bárcenas Gabriel , Albores‐Velasco Martha , Percino Judith , Chapela Víctor , Ocampo Miguel A.
Published: March 2010

The mechanism and kinetics of the spontaneous copolymerization of styrene (S) and maleic anhydride (MA) in the presence of 4‐oxo‐TEMPO nitroxide (N) were studied. Experiments were performed at 125 °C varying the S/MA and the N/S ratios and the evolution of conversion was measured by dilatometry up to 20% conversion. Clean induction periods or severe retardation in the initial stage of the reaction were observed. From a proposed kinetic mechanism a mathematical model was built, which was used for fitting the relevant kinetic constants for the self‐initiation steps, and the ratio ${{\bar {k}_{\rm p} } \mathord{\left/ {\vphantom {{\bar {k}_{\rm p} } {\bar {k}_{\rm t}^{{1 \mathord{\left/ {\vphantom {1 2}} \right. \kern-\nulldelimiterspace} 2}} }}} \right. \kern-\nulldelimiterspace} {\bar {k}_{\rm t}^{{1 \mathord{\left/ {\vphantom {1 2}} \right. \kern-\nulldelimiterspace} 2}} }}$. The model performs well in certain concentration regimes, but it remains a challenge to completely understand this complex system in other concentration regimes.

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