bluuebunny/crossref_metadata_2025 huggingface dataset:
Resonant frequency tunable dual‐band monopole antenna with the ground shorted inset sleeve
Authors: Baik J.‐W. , Kim Y.‐S.
Published: May 2010

The simple printed monopole antenna for dual‐band operation with tunability is proposed. It uses the ground shorted inset sleeve of which the length is controlled. This type of antenna can easily produce dual‐band characteristics without any additional metal strips or radiating elements. The omni‐directional radiation patterns at both design frequencies are similar to those of a conventional monopole. Details of the proposed monopole design and experimental results are demonstrated in this letter. © 2010 Wiley Periodicals, Inc. Microwave Opt Technol Lett 52: 1731–1733, 2010; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.25308
New materials for electromagnetic shielding: Metal foams with plasma properties
Authors: Monti Giuseppina , Catarinucci Luca , Tarricone Luciano
Published: May 2010

In this article, the use of metal foams for shielding problems is investigated on the bases of an “effective medium approach.” Specifically, a shielding effectiveness analysis has been performed by modeling metal foams as a homogeneous medium described by a plasma dispersion profile.The suggested approach is experimentally validated demonstrating that metal foams behave like a plasma medium, with a plasma frequency in the microwave range. The proposed effective medium approach has also been implemented both with a proprietary and with a commercial full‐wave simulator. Results demonstrate that, by using the plasma model, general electromagnetic analysis of metal foams can be performed with common simulators and with affordable computational efforts. © 2010 Wiley Periodicals, Inc. Microwave Opt Technol Lett 52: 1700–1705, 2010; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.25309
A beam‐switchable coupled feeding network in X‐band
Authors: Im Yun‐Taek , Lee Jee‐Hoon , Jeong Yong‐Woo , Lee Sang‐Ik , Park Seong‐Ook
Published: May 2010

An antenna feeding network is proposed for a driving system.It consists of branch line couplers, Wilkinson power dividers, and asymmetric delay lines. Using an orthogonal beam property and an antenna sharing technique, its radiation patterns are measured at 10 GHz. The measured beam coverage angle was 70° (−35° to +35°) in the five input ports by using eight radiating elements. © 2010 Wiley Periodicals, Inc. Microwave Opt Technol Lett 52: 1865–1868, 2010; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.25313
Small microstrip‐fed printed monopole antenna for UWB application
Authors: Ojaroudi M. , Ebrahimian H. , Ghobadi Ch. , Nourinia J.
Published: May 2010

In this article by using the Babinet's Equivalence Principle and self‐complementary structure, we present a novel printed monopole antenna for ultra‐wideband (UWB) applications. The proposed antenna consists of a ground plane and radiating patch with a slot and a sleeve structure, which provides fractional bandwidth of more than 100%. © 2010 Wiley Periodicals, Inc. Microwave Opt Technol Lett 52: 1756–1761, 2010; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.25318
Fast inhomogeneous plane wave algorithm for scattering from PEC body of revolution
Authors: Rui Xi , Hu Jun , Liu Qing Huo
Published: May 2010

To solve large‐scale electromagnetic scattering problems for bodies of revolution, a fast inhomogeneous plane wave algorithm (FIPWA) is developed. By using the Weyl identity and designing a proper integral path, the aggregation and disaggregation factors can be computed efficiently in FIPWA. Both the memory and CPU time requirements are significantly reduced for large scale BOR problems over the method of moments. Numerical results are given to demonstrate the validity and the efficiency of the FIPWA method to perfect conductors, but the method can be extended to dielectric BORs. © 2010 Wiley Periodicals, Inc. Microwave Opt Technol Lett 52: 1915–1922, 2010; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.25319
Investigations on a multiband microstrip‐fed inverted‐F antenna with ground slots
Authors: Razali Ahmad R. , Bialkowski Marek E. , Boldaji Ashkan , Tsai Feng‐Chi E.
Published: May 2010

This article describes two designs of a Coplanar Inverted F Antenna (CIFA) which employ a microstripline as a feeding element and open‐end ground slots to obtain a multiband operation in the frequency band of 2.4 and 6 GHz.Investigations are performed with regard to two different orientations of ground slots one being parallel and the other perpendicular to CIFA. Initially, the CIFA element is designed to operate at 2.45 GHz in the absence of ground slots. Next, open‐end ground slots suitably coupled to the feeding microstripline are added to obtain operation at higher frequencies. The two configurations of multiband CIFA are fabricated and experimentally assessed in terms of return loss, radiation pattern, and gain. The radiation mechanism is studied through the simulated distributions of surface current densities. © 2010 Wiley Periodicals, Inc. Microwave Opt Technol Lett 52: 1713–1719, 2010; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.25321
Flexible V‐band optical millimeter‐wave carrier generation techniques using optical injection locked Fabry‐Pérot laser diodes
Authors: Hong Moon‐Ki , Won Yong‐Yuk , Han Sang‐Kook
Published: May 2010

Novel schemes, for V‐band (60‐GHz frequency range) optical millimeter‐wave (mm‐wave) carrier generation in radio‐over‐fiber system, are proposed and experimentally demonstrated that are based on injection‐locked Fabry‐Pérot laser diodes.Dual‐parallel and cascaded structures are individually proposed to generate the mm‐wave carrier. We could improve the suppression ratio (SR) of the carrier suppressed optical signal as well as reduce RF phase noise of the mm‐wave carrier by using the proposed schemes. The SR improvement of the carrier suppressed optical signal of 20 dB was verified. 60‐GHz mm‐wave carrier of enhanced signal quality could be also achieved. Its peak power and RF phase noise were obtained as about −40 dBm and less than −95 dBm, respectively, which was suitable for 60‐GHz data transmission. © 2010 Wiley Periodicals, Inc. Microwave Opt Technol Lett 52: 1685–1691, 2010; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.25322
Three to two curve fractal folded dipole antenna for RFID application
Authors: Zhou Jianhua , Luo Yong , You Baiqiang , Lin Bin
Published: May 2010

A 3/2 curve fractal dipole antenna was proposed for radio‐frequency identification application, with mirror and photonic bandgap structure. Some properties of the antenna, such as return loss and bandwidth have been simulated and investigated. The results show that the absolute bandwidths of antenna are up to 0.28 GHz and 0.41 GHz at 2.4 GHz and 5.8 GHz, respectively accordingly the relative bandwidths up to 9.76% and 6.87%. With a prototype fabricated, we also verified the good performance of the antenna through the comparison of measured and simulated results. © 2010 Wiley Periodicals, Inc. Microwave Opt Technol Lett 52: 1827–1830, 2010; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.25324
Four‐channel fiber loop ring‐down pressure sensor with temperature compensation based on neural networks
Authors: Gao Yang , Qiu Yishen , Chen Huaixi , Huang Yan , Li Gaoming
Published: May 2010

A four‐channel fiber loop ring‐down pressure sensor with temperature compensation based on neural networks is described.This fiber ring‐down pressure sensor makes use of the principle of time division multiplexing, which consists of series and parallel fiber loops. The laser pulses from four‐channels can be acquired by only one detector and the four pressure values are measured synchronously in our experiment. Taking mode dispersion in multimode fiber into consideration, the maximum multiplexing number is discussed. In addition, temperature compensation based on neural networks has been successfully used in our experiment, to eliminate the disturbance of environmental temperature. © 2010 Wiley Periodicals, Inc. Microwave Opt Technol Lett 52: 1796–1799, 2010; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.25326
A band‐notched CPW fed antenna with ring ground for ultra‐wideband applications
Authors: Guo Qingxin , Li Zengrui , Wang Junhong , Ju Jilong
Published: May 2010

A new CPW‐fed antenna with band‐notched is proposed for ultra‐wideband antenna applications. It consists of a ring strip connecting with two triangle patches as the ground and a rectangular patch connecting with a strip as the radiator and feeding line. A narrow slot is embedded in the radiator to obtain notched‐band characteristics within bandwidth of 5–6 GHz. Simulated results gotten by FDTD method are given and compared with the experimental results. Measured results show that the antenna can cover a bandwidth from 2.5 to 10.7 GHz for VSWR < 2 except the notched‐band. © 2010 Wiley Periodicals, Inc. Microwave Opt Technol Lett 52: 1691–1694, 2010; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.25333
Design on a broadband circularly polarized slot antenna
Authors: Gao Xiang Jun , Zhu Li , Wang Guangming
Published: May 2010

In this article, a novel broadband circularly polarized (CP) slot antenna is proposed and fabricated, in which, a simple perturbation configuration with a narrow rectangular slot etched near the square slot is used for perfect CP operation. Through simulating and testing, the broad impedance bandwidth of 57.6% (VSWR < 2.0) and the 3‐dB axial ratio bandwidth of 50.2% are achieved. This slot antenna will be widely used in communication field. © 2010 Wiley Periodicals, Inc. Microwave Opt Technol Lett 52: 1912–1915, 2010; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.25337
Design and implementation of penta‐band PCB embedded antenna including LTE700 for mobile handset
Authors: Kwak Yong Soo , Park Sung Koo , Jo JaeHoon , Cho Bum Jin , Jeong Seong Tae , Byun Joon Ho , Kim Austin S.
Published: May 2010

In this article, multi‐band antenna covering LTE700/GSM850/GSM900/DCS1800/PCS1900 for mobile terminal is presented.The proposed capacitive feeding antenna is a IFA type antenna and implemented as a PCB embedded antenna (PEA). Broad bandwidth in low‐band is achieved using pattern overlapped capacitive feeding. Simulation is conducted to verify broad low‐band and multi‐band operation using HFSS and experimental results are also presented. © 2010 Wiley Periodicals, Inc. Microwave Opt Technol Lett 52: 1909–1912, 2010; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.25338
A voltage sensor based on a singlemode–multimode–singlemode fiber structure
Authors: Hatta Agus Muhamad , Semenova Yuliya , Rajan Ginu , Farrell Gerald
Published: May 2010

A voltage sensor based on a singlemode–multimode–singlemode (SMS) fiber structure, attached to a piezoelectric (PZT), used in a ratiometric optical power measurement scheme is proposed. The elongation of the PZT due to an applied voltage induces a strain on the SMS fiber structure and in turn results in a change in the transmission loss response of the SMS fiber structure. It is found that at selected wavelengths, a strong voltage dependence for the transmission loss of the SMS fiber structure can be achieved. The voltage information can be obtained from the power ratio of the system, assuming the system is calibrated. The proposed voltage sensor offers a simpler configuration when compared to other fiber optic voltage sensors. © 2010 Wiley Periodicals, Inc. Microwave Opt Technol Lett 52: 1887–1890, 2010; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.25339
Very compact coupled fed loop antenna for 2.4‐GHz WLAN applications
Authors: Su Saou‐Wen , Hong Tzi‐Chieh , Chang Fa‐Shian
Published: May 2010

A novel, coupled fed loop antenna with a small form factor for wireless local area network operation in the 2.4 GHz band is presented.The antenna has a very compact structure with the dimensions 29.75 mm × 5 mm and consists of a half‐wavelength loop and a coupling feed, all printed in a coplanar configuration on a 0.4‐mm thick FR4 substrate. The antenna was easily fed by using a 50‐Ω minicoaxial cable, allowing it to have much flexibility in the placement in a defined location. The results show that good input matching over the 2400–2484 MHz band can be achieved by tuning the coupling‐pad size and the loop width. Good omnidirectional radiation patterns were also observed. Details of a design prototype are described and discussed. © 2010 Wiley Periodicals, Inc. Microwave Opt Technol Lett 52: 1883–1887, 2010; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.25340
Study of the effect of the slot dimension on the properties of a planar ultra‐wideband antenna
Authors: Barbarino Sebastiano , Consoli Fabrizio
Published: May 2010

The effect of the slot dimension on the features of a typical planar antenna for UWB communications is described here. Many prototypes, each having slot of different width, have been studied and realized, and the comparison between simulations and measurements is shown. © 2010 Wiley Periodicals, Inc. Microwave Opt Technol Lett 52: 1813–1817, 2010; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.25343
Composite right/left‐handed band‐pass filters with wide fractional bandwidth based on dual‐metal‐plane structure
Authors: Lin Shih‐Cheng
Published: May 2010

Composite right/left‐handed band‐pass filters with wide fractional bandwidth are implemented based on the proposed dual‐metal‐plane configuration.With proper design of the symmetric composite right/left‐handed unit cell composed with arbitrarily adjustable lumped‐elements, the passband and the fractional bandwidth can be constructed. Specifically, the implemented filters possess relatively achievable wide bandwidth in comparison with the conventional filters. For demonstration, two dual‐plane filters at different center frequencies with distinct factional bandwidth are designed and fabricated. These two filters exhibit good frequency selectivity around the passband. In addition, the measured results show good agreement with the simulated ones. © 2010 Wiley Periodicals, Inc. Microwave Opt Technol Lett 52: 1810–1813, 2010; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.25344
Artificial magnetic surface for circular polarization improvement
Authors: Carrubba E. , Monorchio A. , Manara G.
Published: May 2010

A novel approach to improve the circular polarization properties of a small elliptically polarized (EP) radiating element is presented. The enhancement in circular polarization is obtained by mounting the radiating element close to an artificial magnetic conductor (AMC). To explain the antenna operating principle, two different typologies of radiating element have been initially considered, i.e., a small spiral antenna and a dipole. Both antennas are EP, but the excited current distribution on the AMC screen are circular and linear, respectively. We inferred that only a circular current distribution determines the XPD improvement in correspondence of the AMC resonances. The prototype of the small spiral antenna in the vicinity (λ0/18) of the AMC screen has been manufactured and tested. Measurements confirmed a remarkable improvement in spiral cross polarization discrimination (XPD) in correspondence of the two AMC resonances. The dual‐band behavior of the AMC could be exploited in applications where multifrequency operation is required. The low profile structure is characterized by an overall thickness of 1.1 cm, which corresponds to ∼λ0/12 at the centre of the operating band. © 2010 Wiley Periodicals, Inc. Microwave Opt Technol Lett 52: 1782–1786, 2010; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.25345
An embedded multilayer LTCC band‐pass filter using U‐type stepped impedance resonator
Authors: Wang Zhigang , Wu Peng , Yan Bo , Guo Yunchuan , Xu Ruimin , Lin Weigan
Published: May 2010

This article proposes a compact multilayer band‐pass filter based on low‐temperature co‐fired ceramic (LTCC) technology.The filter is constructed using U‐type stepped impedance resonators (SIR) with microstrip input and output ports. To validate the proposed filter, a three‐order X‐band Chebyshev band‐pass filter is developed and verified by full‐wave simulation. The proposed filter is fabricated using multilayer LTCC technology and measured using vector network analyzer (VNA). Covering area of the fabricated band‐pass filter is only 15.3 × 6.7 mm2 (including via fences). The filter exhibits an insertion loss of lower than 1.8 dB with a 3.2% bandwidth at a center frequency of 9.5 GHz, and the return loss is better than 10 dB in the pass‐band. © 2010 Wiley Periodicals, Inc. Microwave Opt Technol Lett 52: 1877–1880, 2010; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.25352
Wideband CPW‐fed elliptical monopole antenna
Authors: Sun Xu‐Bao , Cao Mao‐Yong
Published: May 2010

An elliptical monopole antenna with a wide bandwidth is proposed, which is composed of an elliptical monopole patch and a ground plane by uniting a quarter of a disc and a rectangular structure, both printed on the same side of a substrate and fed by a coplanar waveguide (CPW) feeder.The simulated and experimental results demonstrate that this antenna achieves an impedance bandwidth covering 2.6–13.9 GHz for VSWR ≤ 2 and also shows a nearly omnidirectional radiation pattern, which indicates that the proposed antenna performance is suitable for UWB applications. © 2010 Wiley Periodicals, Inc. Microwave Opt Technol Lett 52: 1774–1776, 2010; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.25358
Broadband microwave gas sensor: A coaxial design
Authors: Rossignol J. , Stuerga D. , Jouhannaud J.
Published: May 2010

The method of gas detection by a broadband microwave gas sensor is presented in this article. The principle of this method is to use a sensitive material as substrate of a transmission coaxial line. The sensor represents an open line with an extreme surface in contact with gas. The interaction with the gas and the surface induces a dielectric variation of the substrate. From experimental results, the interaction between the sensitive material and each tested gas present a specific frequency spectrum of the reflection coefficient at the input of the line. The proposed method has the advantage of a compact size, wide bandwidth, simple structure, and capable with all sensitive materials. © 2010 Wiley Periodicals, Inc. Microwave Opt Technol Lett 52: 1739–1741, 2010; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.25359
Charcot–marie–tooth disease with intermediate conduction velocities caused by a novel mutation in the MPZ gene
Authors: Banchs Isabel , Casasnovas Carlos , Montero Jordi , Volpini Victor , Martínez‐matos Juan Antonio
Published: May 2010

Charcot–Marie–Tooth (CMT) disease is a heterogeneous group of inherited sensory and motor neuropathies. Mutations in the gene that encodes for myelin protein zero (MPZ) can produce different phenotypes: CMT1 (with low conduction velocities), CMT2 (less frequent and with unaffected conduction velocities), and CMTID (with intermediate conduction velocities). We report a study of seven patients from a four‐generation family. All the affected members of the family had a typical CMT phenotype, but three of them had calf hypertrophy. The nerve conduction velocities (NCV) in all of them were between 35 and 43 m/s. Molecular study revealed the novel mutation Lys214Met in the MPZ gene. Molecular study of the MPZ gene would be useful in cases of CMT in families with intermediate NCV, especially if no mutations in the GJB‐1 gene are found or there is male‐to‐male transmission. Muscle Nerve, 2010
Characterization of skeletal muscle effects associated with daptomycin in rats
Authors: Kostrominova Tatiana Y. , Hassett Cheryl A. , Rader Erik P. , Davis Carol , Larkin Lisa M. , Coleman Scott , Oleson Frederick B. , Faulkner John A.
Published: May 2010

Daptomycin is a lipopeptide antibiotic with strong bactericidal effects against Gram‐positive bacteria and minor side effects on skeletal muscles. The type and magnitude of the early effect of daptomycin on skeletal muscles of rats was quantified by histopathology, examination of contractile properties, Evans Blue Dye uptake, and effect on the patch repair process. A single dose of daptomycin of up to 200 mg/kg had no effect on muscle fibers. A dose of 150 mg/kg of daptomycin, twice per day for 3 days, produced a small number of myofibers (≤0.22%) with loss of plasma membrane integrity and/or infiltration by neutrophils and/or macrophages. Multiple doses of daptomycin are required for a quantifiable effect on skeletal muscles of rats. Some fibers were Evans Blue Dye–positive but were not yet infiltrated by neutrophils. This suggests that the sarcolemma may be the primary target for the observed effects. Muscle Nerve, 2010
Sequencing protocols to genotype mdx, mdx4cv, and mdx5cv mice
Authors: Banks Glen B. , Combs Ariana C. , Chamberlain Jeffrey S.
Published: May 2010

Currently available polymerase chain reaction (PCR) genotyping methods for point mutations in the mouse dystrophin gene can lead to false positives and result in wasted time and money due to breeding or treating the wrong mice. Here we describe a simple and accurate method for sequencing the point mutations in mdx, mdx4cv, and mdx5cv mice. This method clearly distinguishes between wildtype, heterozygous, and mutant transcripts, and thereby time and money can be saved by avoiding false positives. Muscle Nerve, 2010
Photogeneration of free charge carriers in tenuously packed π conjugated polymer chains
Authors: Menšík Miroslav , Pfleger Jiří , Rybak Andrzej , Jung Jaroslaw , Ulański Jacek , Halašová Klára , Vohlídal Jiří
Published: May 2010

A new theoretical insight into the process of free charge carrier photogeneration in polymers is introduced, based on the fact that increasing intensity of electric field may change the charge dynamics during the dissociation process of geminate pairs of photogenerated charge carriers. These changes are reflected in the model by the variation of internal parameters such as permittivity and effective mass of the hole. We used this approach to modify the model recently designed by Arkhipov, Emelianova and Baessler, describing a thermally activated escape of a hole from a quantum well in a Coulombic field of a localized electron. Our approach is particularly suitable for the description of the charge carrier photogeneration process in a polymer consisted of tenuously packed π conjugated polymer chains, as documented by its application to the experimental results of charge carrier photogeneration in poly{1‐[4‐(trimethylsilyl)phenyl]‐2‐phenylacetylene} measured by the photoinduced discharge (PID) technique. Namely, we have observed that the photogeneration yield of free charge carriers does not exhibit a transition to a plateau at the low electric field limit but a steep slope of its dependence on electric field is found. Compared to previously published models, that even consider a limited dimensionality of the process or charge carrier trapping, a marked improvement of the consistency of calculated values with experimental data was achieved. Copyright © 2010 John Wiley & Sons, Ltd.
Restoring assembly and activity of cystathionine β‐synthase mutants by ligands and chemical chaperones
Authors: Kopecká Jana , Krijt Jakub , Raková Kateřina , Kožich Viktor
Published: May 2010

Misfolding and aggregation of mutant enzymes have been proposed to play role in the pathogenesis of homocystinuria due to cystathionine β‐synthase (CBS) deficiency. Chemical chaperones have been recently shown to facilitate proper assembly of several CBS mutants. To asses the number of patients that may respond to chaperone therapy, we examined the effect of selected CBS ligands and osmolytes on assembly and activity of 27 CBS mutants that represent 70% of known CBS alleles. The mutant enzymes were expressed in a bacterial system, and their properties were assessed by native Western blotting and sensitive liquid chromatography tandem mass spectrometry (LC‐MS/MS) assay, respectively. We studied the chaperoning activity of δ‐aminolevulinic acid (δ‐ALA)—a heme precursor—and of three osmolytes betaine, 2‐aminoethanesulfonic acid (taurine), and glycerol. Fourteen mutants responded by at least 30% increase in the amount of correctly assembled tetramers and enzymatic activity to the coexpressional presence of either 0.5 mM δ‐ALA, 100 mM betaine, and/or 750 mM glycerol. Eight of these mutants (p.R266K, p.P49L, p.R125Q, p.K102N, p.R369C, p.V180A, p.P78R, p.S466L) were rescuable by all of these three substances. Four mutants showed increased formation of tetramers that was not accompanied by changes in activity. Topology of mutations appeared to determine the chaperone responsiveness, as 11 of 14 solvent‐exposed mutations were substantially more responsive than three of 13 buried mutations. This study identified chaperone‐responsive mutants that represent 56 of 713 known patient‐derived CBS alleles and may serve as a basis for exploring pharmacological approaches aimed at correcting misfolding in homocystinuria.
The birth prevalence of lysosomal storage disorders in the Czech Republic: comparison with data in different populations
Authors: Poupětová Helena , Ledvinová Jana , Berná Linda , Dvořáková Lenka , Kožich Viktor , Elleder Milan
Published: May 2010

The aim of this retrospective study was to determine the prevalence of lysosomal storage disorders (LSDs) in the Czech Republic. The data on cases diagnosed between 1975 and 2008 were collected and analyzed. The overall prevalence of LSDs in the Czech population (12.25 per 100,000) is comparable to that reported for the countries with well‐established and advanced diagnostics of LSDs such as the Netherlands (14 per 100,000), Australia (12.9 per 100,000) and Italy (12.1 per 100,000). Relatively higher prevalence of LSDs was reported in the north of Portugal (25 per 100,000). Thirty‐four different LSDs were diagnosed in a total of 478 individuals. Gaucher disease was the most frequent LSD with a birth prevalence of 1.13 per 100,000 births. The most frequent LSD groups were lipidoses, mucopolysaccharidoses, and neuronal ceroid lipofuscinoses, with combined prevalences of 5.0, 3.72, and 2.29 per 100,000 live births, respectively. Glycoproteinoses (0.57 per 100,000 live births), glycogenosis type II (0.37), and mucolipidoses (0.31) rarely occur in the Czech population, and a range of other LSDs have not been detected at all over the past three decades. Knowledge of the birth prevalence and carrier frequency of particular disorders is important in genetic counselling for calculation of the risk for the disorder in the other members of affected families. Earlier diagnosis of these disorders will permit timely intervention and may also result in lowering of the number of newborns with LSDs.
Clone lineages of grape phylloxera differ in their performance onVitis vinifera
Authors: Herbert K.S. , Umina P.A. , Mitrovski P.J. , Powell K.S. , Viduka K. , Hoffmann A.A.
Published: May 2010

Grape phylloxera,Daktulosphaira vitifoliaeFitch, is an important pest of grapevines (Vitis viniferaL.) (Vitaceae). The distribution and frequency of phylloxera clone lineages vary within infested regions of Australia, suggesting the introduction of separate lineages ofD. vitifoliaewith host associations. Virulence levels of particular phylloxera clones may vary onV. vinifera, but much of this evidence is indirect. In this study, we directly tested the performance of phylloxera clones onV. viniferausing an established excised root assay and a new glasshouse vine assessment. In the root assay, grape phylloxera clones differed in egg production and egg to adult survivorship. In the vine assay, clones differed in the number of immature and adult life stages on roots. In addition vine characteristics, including mean stem weight, root weight, leaf chlorophyll and leaf area, were affected by different phylloxera clones. The two most widespread clones displayed high levels of virulence. These results point to only some phylloxera clones being highly virulent onV. vinifera, helping to explain patterns of field damage, phylloxera distributions and continued survival and production ofV. viniferavines in some infested areas.
Global Environmental Encounters in Southwest China: Fleeting Intersections and “Transnational Work”
Authors: Hathaway Michael J.
Published: May 2010

This paper engages with the critical literature on development through a study of transnational environmentalism in China. Within the last decade, international development efforts have become increasingly important in shaping China's encounters with global sensibilities, funds, and projects. The author builds on scholarship that approaches China as a transnational entity and examines the emerging politics of the environment in China. Based on an ethnographic case study of a conservation and development project in Yunnan Province, the paper argues against conceptions that international development agendas can be unilaterally imposed. Rather, it suggests that in order to gain traction, agendas require a variety of agents. These agents create convergences through forms of “transnational work,” by and through particular social engagements. Finally, this paper reveals how such convergences remain tenuous and fleeting, and can be quickly dissolved when one side or another changes its orientation.
Response surface optimization of the cultivation conditions and medium components for the production of folate by Streptococcus thermophilus
Authors: Iyer Ramya , Tomar Sudhir Kumar , Singh Ashish Kumar
Published: May 2010

Optimization of the cultivation conditions and medium components for folate production by the highest folate producing Streptococcus thermophilus strain RD102 was carried out using a 23 central composite design and surface modelling method of response surface methodology. As folate production was observed to be growth-associated, hence the desired responses selected for the optimization were both folate production and growth. The selected factors based on preliminary investigations were incubation period, concentrations of p-amino benzoic acid (PABA) the growth precursor, and lactose as carbon source. The optimum concentrations of PABA and lactose were found to be 300 μm and 3% respectively at 72 h incubation. The optimized conditions resulted in an increase in folate production by 26% compared with control conditions (0% PABA and lactose at 37°C). Using the method of experimental factorial design and response surface analysis, it was possible to determine optimal operating conditions to obtain a higher folate production by Strep. thermophilus. Therefore, this study constitutes a step in developing strategies to modulate the folate level to a higher level.
Transfer of linoleic and linolenic acid from feed to milk in cows fed isoenergetic diets differing in proportion and origin of concentrates and roughages
Authors: Khiaosa-ard Ratchaneewan , Klevenhusen Fenja , Soliva Carla R , Kreuzer Michael , Leiber Florian
Published: May 2010

The transfer of ingested α-linolenic acid (ALA) and linoleic acid (LA) determines the nutritional quality of milk, but the factors determining this transfer are unclear. The present experiment investigated the influence of roughage to concentrate proportions and the effect of concentrate types on milk fat composition. Respectively, six lactating dairy cows were fed one of three isoenergetic (5·4±0·05 MJ net energy for lactation/kg dry matter; DM) and isonitrogenous (215±3·5 g crude protein/kg DM) diets, consisting of ryegrass hay only (33 g fatty acids/kg DM; ALA-rich, no concentrate), maize (straw, whole maize pellets and gluten; 36 g fatty acids/kg DM; LA-rich; 560 g concentrate/kg DM), or barley (straw and grain plus soybean meal; 19 g fatty acids/kg DM; LA-rich; 540 g concentrate/kg DM). The fatty acid composition of feeds and resulting milk fat were determined by gas chromatography. The ALA concentration in milk fat was highest (P<0·001) with the hay-diet, but the proportionate transfer of ALA from diet to milk was lower (P<0·001) than with the maize- or barley-diets. The LA concentration in milk fat was highest with the maize-diet (P<0·05, compared with hay) but relative transfer rate was lower (P=0·01). The transfer rates of ALA and LA were reciprocal to the intake of individual fatty acids which thus contributed more to milk fat composition than did roughage to concentrate proportions. The amount oftrans-11 18:1 in milk fat was lowest with the barley-diet (P<0·001) and depended on the sum of ALA and LA consumed. The milk fat concentration ofcis-9,trans-11 18:2 (rumenic acid) was more effectively promoted by increasing dietary LA (maize) than ALA (hay). Amounts of 18:0 secreted in milk were four (maize) to seven (hay) times higher than the amounts ingested. This was suggestive of a partial inhibition of biohydrogenation in the maize-diet, possibly caused by the high dietary LA level.
Influence of milk quality and production protocol on proteolysis and lipolysis in Monti Dauni Meridionali Caciocavallo cheese
Authors: Albenzio Marzia , Santillo Antonella , Russo Donatella Esterina , Caroprese Mariangela , Marino Rosaria , Sevi Agostino
Published: May 2010

The aim of this study was to assess the effect of milk source and of cheese production protocol on proteolytic and lipolytic pattern of cheese during ripening. The study involved six dairy factories located in Monti Dauni Meridionali area of Southern Italy; three dairy factories processed the milk produced by their own cow herds, while the other three dairy factories processed the milk collected in other dairy farms located in the neighbouring area. Cow milk processed to cheese had different nutritional parameters and hygienic quality. Caciocavallo cheese showed differences in the evolution of proteolysis during ripening and in the intensity of the lipolytic process detected at the end of ripening. The main factors influencing Caciocavallo cheese features were the quality of the starting milk, differences in technological steps such as milk heating, type of starter cultures and coagulant used.
Mechanics of liquid–liquid interfaces and mixing enhancement in microscale flows
Authors: VERGUET STÉPHANE , DUAN CHUANHUA , LIAU ALBERT , BERK VEYSEL , CATE JAMIE H. D. , MAJUMDAR ARUN , SZERI ANDREW J.
Published: May 2010

Experimental work on mixing in microfluidic devices has been of growing importance in recent years. Interest in probing reaction kinetics faster than the minute or hour time scale has intensified research in designing microchannel devices that would allow the reactants to be mixed on a time scale faster than that of the reaction. Particular attention has been paid to the design of microchannels in order to enhance the advection phenomena in these devices. Ultimately, in vitro studies of biological reactions can now be performed in conditions that reflect their native intracellular environments. Liau et al. (Anal. Chem., vol. 77, 2005, p. 7618) have demonstrated a droplet-based microfluidic mixer that induces improved chaotic mixing of crowded solutions in milliseconds due to protrusions (‘bumps’) on the microchannel walls. Liau et al. (2005) have shown it to be possible to mix rapidly plugs of highly concentrated protein solutions such as bovine hemoglobin and bovine serum albumin. The present work concerns an analysis of the underlying mechanisms of shear stress transfer at liquid–liquid interfaces and associated enhanced mixing arising from the protrusions along the channel walls. The role of non-Newtonian rheology and surfactants is also considered within the mixing framework developed by Aref, Ottino and Wiggins in several publications. Specifically, we show that proportional thinning of the carrier fluid lubrication layer at the bumps leads to greater advection velocities within the plugs, which enhances mixing. When the fluid within the plugs is Newtonian, mixing will be enhanced by the bumps if they are sufficiently close to one another. Changing either the rheology of the fluid within the plugs (from Newtonian to non-Newtonian) or modifying the mechanics of the carrier fluid-plug interface (by populating it with insoluble surfactants) alters the mixing enhancement.
On the boundary-layer structure of high-Prandtl-number horizontal convection
Authors: DANIELS P. G.
Published: May 2010

This paper describes the boundary-layer structure of the steady flow of an infinite Prandtl number fluid in a two-dimensional rectangular cavity driven by differential heating of the upper surface. The lower surface and sidewalls of the cavity are thermally insulated and the upper surface is assumed to be either shear-free or rigid. In the limit of large Rayleigh number (R → ∞), the solution involves a horizontal boundary layer at the upper surface of depth of order R−1/5 where the main variation in the temperature field occurs. For a monotonic temperature distribution at the upper surface, fluid is driven to the colder end of the cavity where it descends within a narrow convection-dominated vertical layer before returning to the horizontal layer. A numerical solution of the horizontal boundary-layer problem is found for the case of a linear temperature distribution at the upper surface. At greater depths, of order R−2/15 for a shear-free surface and order R−9/65 for a rigid upper surface, a descending plume near the cold sidewall, together with a vertically stratified interior flow, allow the temperature to attain an approximately constant value throughout the remainder of the cavity. For a shear-free upper surface, this constant temperature is predicted to be of order R−1/15 higher than the minimum temperature of the upper surface, whereas for a rigid upper surface it is predicted to be of order R−2/65 higher.
Fully nonlinear periodic internal waves in a two-fluid system of finite depth
Authors: CAMASSA R. , RUSÅS P.-O. , SAXENA A. , TIRON R.
Published: May 2010

Periodic travelling wave solutions for a strongly nonlinear model of long internal wave propagation in a two-fluid system are derived and extensively analysed, with the aim of providing structure to the rich parametric space of existence of such waves for the parent Euler system. The waves propagate at the interface between two homogeneous-density incompressible fluids filling the two-dimensional domain between rigid planar boundaries. The class of waves with a prescribed mean elevation, chosen to coincide with the origin of the vertical (parallel to gravity) axis, and prescribed zero period-average momentum and volume-flux is studied in detail. The constraints are selected because of their physical interpretation in terms of possible processes of wave generation in wave-tanks, and give rise to a quadrature formula which is analysed in parameter space with a combination of numerical and analytical tools. The resulting model solutions are validated against those computed numerically from the parent Euler two-layer system with a boundary element method. The parametric domain of existence of model periodic waves is determined in closed form by curves in the amplitude–speed (A, c) parameter plane corresponding to infinite period limiting cases of fronts (conjugate states) and solitary waves. It is found that the existence domain of Euler solutions is a subset of that of the model. A third closed form relation between c and A indicates where the Euler solutions cease to exist within the model's domain, and this is related to appearance of ‘overhanging’ (multiple valued) wave profiles. The model existence domain is further partitioned in regions where the model is expected to provide accurate approximations to Euler solutions based on analytical estimates from the quadrature. The resulting predictions are found to be in good agreement with the numerical Euler solutions, as exhibited by several wave properties, including kinetic and potential energy, over a broad range of parameter values, extending to the limiting cases of critical depth ratio and extreme density ratios. In particular, when the period is sufficiently long, model solutions show that for a given supercritical speed waves of substantially larger amplitude than the limiting amplitude of solitary waves can exist, and are good approximations of the corresponding Euler solutions. This finding can be relevant for modelling field observations of oceanic internal waves, which often occur in wavetrains with multiple peaks.
Rapid granular flows down inclined planar chutes. Part 1. Steady flows, multiple solutions and existence domains
Authors: WOODHOUSE MARK J. , HOGG ANDREW J. , SELLAR ALISTAIR A.
Published: May 2010

The highly agitated flow of grains down an inclined chute is modelled using a kinetic theory for inelastic collisions. Solutions corresponding to steady, fully developed flows are obtained by solving numerically a nonlinear system of ordinary differential equations using a highly accurate pseudospectral method based on mapped Chebyshev polynomials. The solutions are characterized by introducing macroscopic, depth-integrated variables representing the mass flux of flowing material per unit width, its centre-of-mass and the mass supported within the flowing layer, and the influence of the controlling parameters on these solutions is investigated. It is shown that, in certain regions of parameter space, multiple steady solutions can be found for a specified mass flux of material. An asymptotic analysis of the governing equations, appropriate to highly agitated flows, is also developed and these results aid in the demarcation of domains in parameter space where steady solutions can be obtained.
Rapid granular flows down inclined planar chutes. Part 2. Linear stability analysis of steady flow solutions
Authors: WOODHOUSE MARK J. , HOGG ANDREW J.
Published: May 2010

The linear stability of steady solutions for a rapid granular flow down an inclined chute, modelled using a kinetic theory continuum model, is analysed. The previous studies of Forterre & Pouliquen (J. Fluid Mech., vol. 467, 2002, p. 361) and Mitarai & Nakanishi (J. Fluid Mech., vol. 507, 2004, p. 309) are extended by considering fully three-dimensional perturbations, allowing variations in both the cross-slope and downslope directions, as well as normal to the base. Our results demonstrate the existence of three qualitatively different unstable perturbations, each of which can be the most rapidly growing instability for different steady flows. By considering the linear stability of many steady solutions along macroscopic flow curves, we show that linear stability occurs in only a small part of parameter space, and furthermore the regions of linear instability do not correlate with density inversion of the underlying steady solutions. Our results suggest that inelastic clustering is the dominant instability mechanism.
Three-dimensional direct numerical simulation of a turbulent lifted hydrogen jet flame in heated coflow: a chemical explosive mode analysis
Authors: LU T. F. , YOO C. S. , CHEN J. H. , LAW C. K.
Published: May 2010

A chemical explosive mode analysis (CEMA) was developed as a new diagnostic to identify flame and ignition structure in complex flows. CEMA was then used to analyse the near-field structure of the stabilization region of a turbulent lifted hydrogen–air slot jet flame in a heated air coflow computed with three-dimensional direct numerical simulation. The simulation was performed with a detailed hydrogen–air mechanism and mixture-averaged transport properties at a jet Reynolds number of 11000 with over 900 million grid points. Explosive chemical modes and their characteristic time scales, as well as the species involved, were identified from the Jacobian matrix of the chemical source terms for species and temperature. An explosion index was defined for explosive modes, indicating the contribution of species and temperature in the explosion process. Radical and thermal runaway can consequently be distinguished. CEMA of the lifted flame shows the existence of two premixed flame fronts, which are difficult to detect with conventional methods. The upstream fork preceding the two flame fronts thereby identifies the stabilization point. A Damköhler number was defined based on the time scale of the chemical explosive mode and the local instantaneous scalar dissipation rate to highlight the role of auto-ignition in affecting the stabilization points in the lifted jet flame.
Deformation of soap films pushed through tubes at high velocity
Authors: DOLLET BENJAMIN , CANTAT ISABELLE
Published: May 2010

The behaviour of soap films pushed through tubes at large velocities, up to several metres per second, is investigated in this paper. The film shape deviates from its equilibrium configuration perpendicular to the walls and gets curved downstream. A simple model relates the radius of curvature of the film to the friction in the lubrication films touching the wall, and the scaling of Bretherton (J. Fluid Mech., vol. 10, 1961, pp. 166–188) holds up to surprisingly high velocities, at which the capillary and Weber numbers are no longer small parameters. The tube geometry is varied and accounted for through the notion of hydraulic diameter. A limit of stability of the films, beyond which they burst or evolve unsteadily, is predicted, and it quantitatively captures the observations. The new questions raised by our results on the dissipation in soap films are discussed, especially the role of Plateau borders and inertial effects.
Spatial structure of a turbulent boundary layer with irregular surface roughness
Authors: WU Y. , CHRISTENSEN K. T.
Published: May 2010

Particle image velocimetry experiments were performed to study the impact of realistic roughness on the spatial structure of wall turbulence at moderate Reynolds number. This roughness was replicated from an actual turbine blade damaged by deposition of foreign materials and its features are quite distinct from most roughness characterizations previously considered as it is highly irregular and embodies a broad range of topographical scales. The spatial structure of flow over this rough surface near the outer edge of the roughness sublayer is contrasted with that of smooth-wall flow to identify any structural modifications due to roughness. Hairpin vortex packets are observed in the outer layer of the rough-wall flow and are found to contribute heavily to the Reynolds shear stress, consistent with smooth-wall flow. While similar qualitative consistency is observed in comparisons of smooth- and rough-wall two-point correlations, some quantitative differences are also apparent. In particular, a reduction in the streamwise extent of two-point correlations of streamwise velocity is noted which could be indicative of a roughness-induced modification of outer-layer vortex organization. Proper orthogonal decomposition analysis reveals the streamwise coherence of the larger scales to be most sensitive to roughness while the spatial characteristics of the smaller scales appear relatively insensitive to such effects.
‘The Kenyas we don't want’: popular thought over constitutional review in Kenya, 2002
Authors: Diepeveen Stephanie
Published: May 2010

Evidence of political instability in Kenya emerged through the organised and spontaneous violence following the 2007 elections. Understanding the underlying reasons for popular contestations of power and involvement in violence depends on understanding Kenyans' perceptions of existing and desirable political institutions. By analysing recommendations made in the Constitution of Kenya Review Commission public hearings in each province in 2002, this article explores the viewpoints of those outside high politics in Kenya, teasing out the continuities and divergences in popular thought about political relations in Kenya at the end of the Moi years, and thus providing insights into how Kenyans understand their relationship with those in power, revealing that amidst diverse experiences, disillusionment pervades Kenyans' perceptions of political relations.