bluuebunny/crossref_metadata_2025_split huggingface dataset:
The design of printed rectangular slot antenna with a small isosceles triangle slot for Wimax applications
Authors: Chen Wen‐Shan , Kao Bao‐Hung 
Published: June 2006

AbstractPrinted rectangular slot antenna fed by a 50‐Ω microstrip line with a small isosceles triangle slot for broadband operation is presented. Both impedance and radiation characteristics of this antenna are studied. Experimental results indicate that a 1:2 VSWR bandwidth of 3.97 GHz is achieved at operating frequencies around 1.85–5.83 GHz. By the proposed design, the broadband property and excellent impedance matching lead to practical performance that are good radiation patterns and antenna gain. The design of the proposed antenna is suitable for Wimax applications, which cover the band of 2.495–2.69, 3.4–3.8, and 5.25–5.85 GHz. © 2006 Wiley Periodicals, Inc. Microwave Opt Technol Lett 48: 1821–1824, 2006; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.21792
Material reflector for cellular/PCS array applications
Authors: Lee K. W. , Rojas R. G. 
Published: June 2006

AbstractA material reflector composed of a metallic ground plane, resistive sheets and, if necessary, elongated rails along the edges of the sheet reflector is presented. The optimized design achieves a front‐to‐back ratio greater than 30 dB with minimal change in pattern beamwidth. © 2006 Wiley Periodicals, Inc. Microwave Opt Technol Lett 48: 1890–1894, 2006; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.21793
Effective constitutive parameters of structured chiral metamaterials
Authors: Ouchetto O. , Zouhdi S. , Razek A. , Miara B. 
Published: June 2006

AbstractIn this paper we present a novel procedure for predicting the effective constitutive parameters of three‐dimensional periodic materials with chiral component phases. The method combines the mathematical homogenization technique and the finite element method. The homogenization is accomplished by solving a local problem in the unit cell. © 2006 Wiley Periodicals, Inc. Microwave Opt Technol Lett 48: 1884–1886, 2006; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.21795
Radiation phenomena from pseudochiral cylinders at plane wave incidence
Authors: Polewski Michael , Lech Rafal , Mazur Jerzy 
Published: June 2006

AbstractThe influence of pseudochiral medium on the scattering patterns of cylindrical pseudochiral objects is presented. Combination of an extended iterative scattering procedure and the orthogonal expansion method is used to investigate multiple cylindrical obstacles. The far scattered field patterns as well as transmission characteristics of rectangular waveguides are presented for different configurations of pseudochiral and isotropic obstacles. © 2006 Wiley Periodicals, Inc. Microwave Opt Technol Lett 48: 1880–1884, 2006; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.21796
Electromagnetic wave scattering by a set of axially symmetric Ω‐medium cylinder
Authors: Lech Rafal , Kowalczyk Piotr , Mazur Jerzy 
Published: June 2006

AbstractThis paper presents the analysis of electromagnetic field scattering by a set of cylindrical objects made of pseudochiral material located in rectangular waveguide junctions and free space. Presented approach is based on the iterative scattering procedure (ISP) and the orthogonal expansion method. Several numerical examples for open and closed problems were presented. © 2006 Wiley Periodicals, Inc. Microwave Opt Technol Lett 48: 1876–1880, 2006; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.21797
Direct time domain solution for dielectric structure with time derivatives of the potential functions by central difference
Authors: Lee Wonwoo , Sarkar Tapan K. 
Published: June 2006

AbstractIn this article, we presented a new direct time domain solution for three‐dimensional arbitrarily shaped dielectric structures. To solve the time domain electric field integral equation (EFIE), a central differencing scheme is used to evaluate the time derivatives of the potential functions. The solution method is based on the method of moments (MoM) and marching‐on‐in‐time (MOT) technique. An implicit method with the time derivative evaluated by central difference is described to solve the EFIE, and the detailed mathematical procedures are included along with representative numerical results. © 2006 Wiley Periodicals, Inc. Microwave Opt Technol Lett 48: 1795–1801, 2006; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.21799
Equivalence between substrate‐integrated (SIRW) rectangular waveguide short‐circuit load and its equivalent rectangular waveguide short‐circuit load
Authors: Che Wenquan , Xu Lei , Wang Dapeng , Geng Liang , Deng Kuan , Chow Y. L. 
Published: June 2006

AbstractSubstrate integrated rectangular waveguide (SIRW) is an artificial rectangular waveguide (RW) constructed in planar substrate with two rows of periodic metallized posts or slots. In this letter, the equivalence formula between the locations of the corresponding short circuits by cylinder walls and by the solid wall was derived, based on the former width equivalence formula of the SIRW and its equivalent RW [(11)]]. The theoretical and simulation results are given for the SIRW short load and RW short load, good agreements have been observed. Such equivalences are convenient for the design of small waveguides, of millimeter wave, in a multilayer circuit structure, such as the LTCC etc. © 2006 Wiley Periodicals, Inc. Microwave Opt Technol Lett 48: 1694–1698, 2006; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.21805
Return loss of three types of arching bond wire structures for RF and microwave circuit applications
Authors: Chen Hsing‐Yi , Tai Chen‐Hsien 
Published: June 2006

AbstractThe S‐parameters of a gold wire bonded in air to two microstrip lines are validated by measurements and HFSS software simulations at frequencies of 0.04–6 GHz. From simulation results and measurement data, it is found that an arching bond wire with a smaller arc angle can minimize the return loss. From simulations, it is also found that the return loss can be improved, and operation frequency shifts can be achieved by using multiple wires placed in parallel in bond wire arrays. © 2006 Wiley Periodicals, Inc. Microwave Opt Technol Lett 48: 1701–1704, 2006; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.21807
Compact broadband circularly polarized microstrip antenna
Authors: Zhang Jun‐Wen , Zhong Shun‐Shi , Xu Sai‐Qing 
Published: June 2006

AbstractA compact broadband circularly polarized (CP) microstrip antenna is proposed, in which a square patch printed on the dielectric substrate is fed by a Wilkinson power divider through two orthogonal H‐shaped slots. Comparing with the conventional broadband CP antenna with an air or foam layer, the size of this antenna is reduced significantly and its fabrication is easier. The 10 dB return loss bandwidth of 45.9% and 2 dB axial‐ratio CP bandwidth of 17% were measured. © 2006 Wiley Periodicals, Inc. Microwave Opt Technol Lett 48: 1730–1732, 2006; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.21808
Phase verification of compact multilayered low temperature co‐fired ceramic composite right‐/left‐handed transmission line
Authors: Rajab Khalid Z. , Mittra Raj , Lanagan Michael 
Published: June 2006

AbstractA novel compact multilayered composite right‐/left‐handed (CRLH) transmission line (TL), fabricated using low‐temperature cofired ceramic (LTCC) technology, is demonstrated. In common with the conventional planar CRLH lines, the signal in the multilayered CRLH TL propagates along a defined path; however with the use of parallel‐plate capacitors to create the series capacitances and loop inductors to create the shunt inductances, the size of the TL is significantly reduced compared to that of the planar CRLH TL. Phase‐portraits in the near‐field region as well as far‐field patterns are used to verify the operation in both the left‐ and the right‐handed frequency regions. © 2006 Wiley Periodicals, Inc. Microwave Opt Technol Lett 48: 1792–1795, 2006; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.21809
1H and 13C NMR assignments and X‐ray structures for three monocyclic benzoannelated dilactam polyethers
Authors: Smith Gary L. N. , Alguindigue Susan S. , Khan Masood A. , Powell Douglas R. , Taylor Richard W. 
Published: June 2006

AbstractThree monocyclic polyether dilactams, 17,18‐dihydro‐5H, 9H‐dibenzo[e,n]1,4,10,7,13trioxadiazacyclopentadecine‐6,10(7H,11H)‐dione (1); 9,10,20,21‐tetrahydro‐5H, 12H‐dibenzo[e,q]1,4,10,13,7,16tetraoxadiazacyclooctadecine‐6, 13(7H,14H)‐dione (2); and 6,7,9,10‐tetrahydro‐16H, 20H‐dibenzo[h,q]1,4,7,13, 10,16tetraoxadiazacyclooctadecine‐17, 21(18H,22H)‐dione (3) were isolated during the synthesis of several benzoannelated cryptands. The complete assignments of the 1H and 13C NMR spectra of 1, 2 and 3 in CDCl3 were made using gCOSY, gHMBC, gHMQC, HMQC, HSQC, and NOESY 1D techniques. The ortho (H2) benzene protons show significant downfield shifts (1.16–1.43 ppm) that are consistent with an exodentate orientation for the amide carbonyl groups. The X‐ray crystal structures of 1, 2 and 3 show that the carbonyl groups adopt an exodentate conformation in the solid state. Copyright © 2006 John Wiley & Sons, Ltd.
Hyperactivation of monkey spermatozoa is triggered by Ca2+ and completed by cAMP
Authors: Ishijima Sumio , Mohri Hideo , Overstreet James W. , Yudin Ashley I. 
Published: June 2006

AbstractDigital image analysis of the flagellar movements of cynomolgus macaque spermatozoa hyperactivated by caffeine and cAMP was carried out to understand the change in flagellar movements during hyperactivation. The degree of flagellar bending increased remarkably after hyperactivation, especially at the base of the midpiece. Mainly two beating patterns were seen in the hyperactivated monkey sperm flagella: remarkably asymmetrical flagellar bends of large amplitude and relatively symmetrical flagellar bends of large amplitude. The asymmetrical bends were often seen in the early stage of hyperactivation, whereas the symmetrical bends executed nonprogressive, figure‐of‐eight movement. Beat frequency of the hyperactivated spermatozoa significantly decreased while wavelength of flagellar waves roughly doubled. To determine the conditions under which the axonemes of hyperactivated sperm flagella have asymmetrical or symmetrical bends, the plasma membranes of monkey spermatozoa were extracted with Triton X‐100 and motility was reactivated with MgATP2− under various conditions. The asymmetrical flagellar bends were brought about by Ca2+, whereas the symmetrical flagellar bends resulted from low levels of Ca2+ and high levels of cAMP. Under these conditions, beat frequency and wavelength of flagellar waves of demembranated, reactivated spermatozoa were similar to those of the hyperactivated spermatozoa. These results suggest that during hyperactivation of monkey spermatozoa intracellular Ca2+ concentrations first rise, and then decrease while cAMP concentrations increase simultaneously. Mol. Reprod. Dev. 1129–1139, 2006. © 2006 Wiley‐Liss, Inc.
Induction of meiotic maturation in mouse oocytes by adenosine analogs
Authors: Downs Stephen M. , Chen Jing 
Published: June 2006

AbstractIn this study we have examined the meiosis‐inducing influence of adenosine analogs in mouse oocytes. When a varied group of nucleosides and nucleotides were tested on overnight cultures of hypoxanthine‐arrested, cumulus cell‐enclosed oocytes (CEO), halogenated adenosine nucleosides, but not native adenosine, exhibited a significant meiosis‐inducing capability. When tested under a variety of conditions, meiotic induction by 8‐bromo‐adenosine (8‐Br‐Ado) and a second adenosine analog, methylmercaptopurine riboside (MMPR), was especially potent in denuded oocytes (DO) compared to CEO and was not dependent on the type of inhibitor chosen to maintain meiotic arrest. Germinal vesicle breakdown (GVB) was stimulated with rapid kinetics and was preceded by an increase in AMP‐activated protein kinase (AMPK) activity. Moreover, compound C, an inhibitor of AMPK, blocked the meiosis‐inducing activities of both adenosine analogs. When tested for an effect on meiotic progression to metaphase II (MII) in spontaneously maturing CEO, 8‐Br‐Ado and the AMPK activator, 5‐aminoimidazole‐4‐carboxamide 1‐β‐D‐ribofuranoside (AICAR), increased the percentage of MII‐stage oocytes, but MMPR decreased this number. Adenosine and inhibitors of de novo purine synthesis had no effect on the completion of maturation, while compound C suppressed this process. These results support the proposition that oocyte AMPK mediates the positive influence of AICAR and 8‐Br‐Ado on both the initiation and completion of meiotic maturation. The role of AMPK in MMPR action is less clear. Mol. Reprod. Dev. 1159–1168, 2006. © 2006 Wiley‐Liss, Inc.
Molecular cloning and characterization of SRG‐L, a novel mouse gene developmentally expressed in spermatogenic cells
Authors: Ma Quanhong , Wang Haikun , Guo Rui , Wang Huizhen , Ge Yehua , Ma Jing , Xue Shepu , Han Daishu 
Published: June 2006

AbstractFull‐length cDNA of a novel mouse gene upregulated in late stages of spermatogenic cells was cloned from mouse testis using overlapping RT‐PCR and RACE. The mRNA of the gene was expressed mainly in diplotene/pachytene spermatocytes, round and elongating spermatids. We named this gene as SRG‐L (Spermatogenesis Related Gene expressed in late stages of spermatogenic cells, GenBank Accession No. AY352586). The tissue‐specific analysis showed a higher expression level in testis and spleen. The gene is mapped on chromosome 8q33.1 and contains 18 exons. The full‐length of cDNA is 2,843 bp with an open reading frame (ORF) of 2,625 bp that encodes a 104 kDa protein (874 amino acids) with a putative transmembrane region. The bioinformatics analysis revealed that the SRG‐L has two conserved regions, transglutaminase‐like homologues domain and D‐serine dehydratase domain, rich phosphorylation sites and methylation sites. The SRG‐L protein was detected in diplotene/pachytene spermatocytes and spermatids by immunohistochemical staining and Western blot. The results suggest that SRG‐L may play definite roles regulating differentiation of germ cells during spermatogenesis, particularly during meiosis and spermiogenesis. Mol. Reprod. Dev. 1075–1083, 2006. © 2006 Wiley‐Liss, Inc.
Adenylyl cyclases in oocyte maturation: A characterization of AC isoforms in bovine cumulus cells
Authors: Lastro Michele , Collins Sarah , Currie W. Bruce 
Published: June 2006

AbstractMammalian oocytes are arrested at the G2/M transition in the meiotic cell cycle. It is well known that a decrease in intraoocyte cAMP concentrations accompanies resumption of meiosis, but the precise trigger of this decrease remains a mystery. Follicular somatic cells are intimately coupled to the oocyte and are thought to transmit maturation signals to the oocyte in response to hormonal stimulation. Here, we investigate the nature of the follicular somatic cell response to hormonal stimulation by identifying and characterizing the adenylate cyclase isoforms present in bovine cumulus cells. RT‐PCR and Western blot analysis revealed the presence of multiple adenylyl cyclase isoforms in bovine granulosa and cumulus cells. Pharmacological manipulation of the AC isoforms showed that multiple isoforms were indeed active. Our data indicate that the PKC inhibited adenylate cyclases IV and VI and the calcium‐stimulated isoform I predominate in bovine cumulus cells. Mol. Reprod. Dev. 1202–1210, 2006. © 2006 Wiley‐Liss, Inc.
Effects of cord motion on diffusion imaging of the spinal cord
Authors: Kharbanda Hardave S. , Alsop David C. , Anderson Adam W. , Filardo Giovanni , Hackney David B. 
Published: June 2006

AbstractMeasurement of diffusion and its dependence on direction has become an important tool for clinical and research studies of the brain. Diffusion imaging of the spinal cord may likewise prove useful as an indicator of tissue damage and axonal integrity; however, it is more challenging to perform diffusion imaging in the cord than in the brain. Here we report a study of the effects of motion on single‐shot fast spin echo (FSE) diffusion tensor imaging (DTI) of the spinal cord. Diffusion imaging was performed at four different times in the cardiac cycle both without and with velocity compensation of the diffusion gradients. Uncompensated diffusion images demonstrated substantial signal loss artifacts in the cord that were strongly dependent on the delay after the pulse‐oximeter trigger. Quantitative diffusion analysis was also strongly affected by this motion artifact. The use of flow‐compensated gradients helped to restore normal signal in the cord, especially at particular trigger delays. Theoretical arguments suggest that improved spatial resolution may help eliminate this signal loss. Even with higher spatial resolution, motion‐related signal attenuation may still occur in diffusion imaging of pathologies that alter the motion of the cord. However, this same cord motion may contain diagnostically valuable information when probed using appropriate diffusion imaging approaches. Magn Reson Med, 2006. © 2006 Wiley‐Liss, Inc.
On extended formulations for the precedence constrained asymmetric traveling salesman problem
Authors: Gouveia L. , Pesneau P. 
Published: June 2006

AbstractIn this article we study the use of formulations with precedence relation variables for the Precedence Constrained Asymmetric Travelling Salesman (PCATS) problem. Contrary to previous articles, the emphasis of this article is on formulations involving exponential sized sets of inequalities and on the development of a cutting plane method together with polynomial routines for separating the new inequalities. Our computational results, taken from a set of benchmark instances, show that our methods improve significantly on most of the best previously known lower bound values. © 2006 Wiley Periodicals, Inc. NETWORKS, Vol. 48(2), 77–89 2006
Deformation mechanism of polystyrene toughened with sub‐micrometer monodisperse rubber particles
Authors: Gao Guanghui , Zhang Jingshu , Yang Haidong , Zhou Chao , Zhang Huixuan 
Published: June 2006

AbstractCore–shell polybutadiene‐graft‐polystyrene (PB‐g‐PS) rubber particles with different ratios of polybutadiene to polystyrene were prepared by emulsion polymerization through grafting styrene onto polybutadiene latex. The weight ratio of polybutadiene to polystyrene ranged from 50/50 to 90/10. These core‐shell rubber particles were then blended with polystyrene to prepare PS/PB‐g‐PS blends with a constant rubber content of 20 wt%. PB‐g‐PS particles with a lower PB/PS ratio (≤70/30) form a homogeneous dispersion in the polystyrene matrix, and the Izod notched impact strength of these blends is higher than that of commercial high‐impact polystyrene (HIPS). It is generally accepted that polystyrene can only be toughened effectively by 1–3 µm rubber particles through a toughening mechanism of multiple crazings. However, the experimental results show that polystyrene can actually be toughened by monodisperse sub‐micrometer rubber particles. Scanning electron micrographs of the fracture surface and stress‐whitening zone of blends with a PB/PS ratio of 70/30 in PB‐g‐PS copolymer reveal a novel toughening mechanism of modified polystyrene, which may be shear yielding of the matrix, promoted by cavitation. Subsequently, a compression‐induced activation method was explored to compare the PS/PB‐g‐PS blends with commercial HIPS, and the result show that the toughening mechanisms of the two samples are different. Copyright © 2006 Society of Chemical Industry
Tokamak und Stellarator – zwei Wege zur Fusionsenergie: Fusionsforschung
Authors: Milch Isabella 
Published: June 2006

AbstractIm Laufe der Fusionsforschung haben sich zwei Bautypen für ein zukünftiges Kraftwerk als besonders aussichtsreich erwiesen: Tokamak und Stellarator. Mit dem geplanten Tokamak‐Experimentalreaktor ITER steht die internationale Fusionsforschung vor der Demonstration eines Energie liefernden Plasmas. Parallel soll die in Greifswald entstehende Forschungsanlage Wendelstein 7‐X die Kraftwerkstauglichkeit des alternativen Bauprinzips der Stellaratoren zeigen.
Sandsturm kontra Wassersturm: Physik im Alltag
Authors: Müller Andreas 
Published: June 2006

AbstractSandstürme ereignen sich oft, “Wasserstürme” hingegen so gut wie nie. Eine Abschätzung zeigt, dass man beim Herauslösen eines Wassertropfens beispielsweise aus dem Meer eine sehr große Kraft benötigt und sehr viel Arbeit verrichten muss. Das scheint die Erklärung zu sein. Führt man eine entsprechende Energiebetrachtung durch, so könnte es durchaus Wasserstürme geben. Diese Überlegung ist zwar mathematisch richtig, aber unvollständig.
Hochtemperatur‐Supraleiter in der Technik: 20 Jahre Hochtemperatur‐Supraleitung
Authors: Malozemoff Alex , Mannhart Jochen , Scalapino Doug 
Published: June 2006

AbstractZwanzig Jahre nach ihrer Entdeckung halten Hochtemperatur‐Supraleiter Einzug in kommerzielle Anwendungen. Elektromotoren und Generatoren, etwa für Schiffe, supraleitende Strombegrenzer und Schwungradsysteme werden gegenwärtig entwickelt. Solche elektrischen Maschinen sind kompakter und leichter als konventionelle und besitzen ein großes Marktpotenzial. Die häufigsten kommerziellen Anwendungen sind gegenwärtig Mikrowellenfilter für Mobilfunk‐Basisstationen, Synchronmotoren zur dynamischen Regelung der Blindleistung in Stromnetzen sind auf dem Markt, erste Maschinen wurden schon kommerziell vertrieben.
Wenn Nudeln fingerhakeln
Authors: Vilgis Thomas 
Published: June 2006

AbstractGekochte Pasta klebt gern zusammen, weil sie ihren eigenen Klebstoff mitbringt. Dieser kann durch die Weißfärbung des Kochwassers gesichtet werden. Die Trübung und ebenfalls die Schaumbildung sind stets auf gelöste beziehungsweise an die Oberfläche getragene Proteine und Stärke zurückzuführen. Je länger Pasta gekocht wird, desto mehr treten derartige Polymerketten aus den Nudeln aus und gehen baden. Aber nicht nur, denn auch die Oberfläche der Nudeln gestaltet sich, hätten wir die Möglichkeit genauer hinzusehen, recht haarig.