bluuebunny/crossref_metadata_2025 huggingface dataset:
Luminescent Platinum(II) Terpyridyl Complexes: Effect of Counter Ions on Solvent‐Induced Aggregation and Color Changes
Authors: Yam Vivian Wing‐Wah , Chan Kenneth Hoi‐Yiu , Wong Keith Man‐Chung , Zhu Nianyong
Published: May 2005

A series of platinum(II) terpyridyl complexes [Pt(tpy)(CCCCH)]X, 1‐X (X=OTf−; PF6−; ClO4−; BF4−; BPh4−); [Pt(tpy)(CCC6H5)]X, 2‐X (X=OTf−; PF6−; ClO4−; BF4−); [Pt(tpy)(CCC6H4OCH3‐4)]OTf, 3‐OTf, and [Pt(4′‐CH3O‐tpy)(CCC6H5)]OTf, 4‐OTf (tpy=2,2′:6′,2′′‐terpyridine, OTf=trifluoromethanesulfonate) were synthesized and their photophysical properties determined. Electronic absorption and emission studies showed the formation of a new band upon increasing the diethyl ether content in an acetonitrile/diethyl ether mixture. This was ascribed to the formation of complex aggregates, the solution color of which is dependent on the nature of the anions. This indicates that counter ions play an important role in governing the degree of aggregation and the extent of interactions within these aggregates. Addition of various anions to solutions of 1‐OTf and 1‐PF6 produced anion‐induced color changes upon solvent‐induced aggregation, indicating that these complexes may serve as potential colorimetric anion probes.
Does a Stabilising Interaction Favouring theZ,ZConfiguration of S‐NSN‐S Systems Exist?
Authors: Tersago Karla , Mandado Marcos , Van Alsenoy Christian , Bagryanskaya Irina Yu. , Kovalev Mikhail K. , Makarov Alexander Yu. , Gatilov Yuri V. , Shakirov Makhmut M. , Zibarev Andrey V. , Blockhuys Frank
Published: May 2005

The existence of the orbital interaction presented in the literature as being the cause for the stabilisation of theZ,Zconfiguration of Ph‐S‐NSN‐S‐Ph (1) and its derivatives in the crystal phase, has been investigated. The results of theoretical calculations at the DFT/B3LYP/6‐311+G* level of theory suggest that such a stabilising interaction might not exist or be extremely weak and that packing forces must be the main cause of the observedZ,Zconfiguration in the solid. To reach this conclusion structural and energetic parameters were combined to study the bonding in these ‐S‐NSN‐S‐ systems. For the analogous Ph‐Se‐NSN‐Se‐Ph (2) in particular the isomeric equilibrium in solution found in the variable‐temperature77Se NMR spectrum indicates that, in the gas phase or in solution, the observedZ,Zconfiguration is not stabilised to a greater extent than theZ,Econfiguration.
Extended Structures and Magnetic Properties of Lanthanide–Copper Complexes with Picolinic Acids as Bridging Ligands
Authors: Wu A‐Qing , Guo Guang‐Hua , Yang Chun , Zheng Fa‐Kun , Liu Xi , Guo Guo‐Cong , Huang Jin‐Shun , Dong Zhen‐Chao , Takano Yoshihiko
Published: May 2005

The first examples of 3d–4f heterometallic complexes containing picolinic acid ligands were synthesized and characterized. Three series of complexes were obtained by the reaction of presynthesized “metallo ligands” Cu(pic)2 and Ln(ClO4)3 in 2:1, 3:1, and 4:1 mole ratios. Complexes 1–3 (denoted as the first series), [LnCu2(pic)4(H2O)6](ClO4)3·H2O (Ln = Sm, Nd, and Pr), are isomorphous and exhibit infinite 1D zigzag chain structures with rare earth ions in tricapped trigonal prismatic coordination. Complexes 4–10 (denoted as the second series), [Ln2Cu5(pic)10(H2O)8](ClO4)6·2H2O (Ln = Gd, Nd, Sm, Dy, Eu, Pr, and Yb), are isomorphous too, and exhibit extended 2D layered structures constituted by Cu(pic)2 moieties bridging the zigzag chains. Complex 11 (denoted as the third‐type complex), {NdCu(pic)2[CO(NH2)2]4(H2O)3}(ClO4)3·[Cu(pic)2]2, exhibits another type of nearly linear chain structure with additional Cu(pic)2 moieties trapped in the lattice by hydrogen bonds. Temperature‐dependent magnetizations of complexes 2–4, 6, and 11 indicate that these complexes follow the Curie–Weiss paramagnetic behavior down to 5 K. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2005)
Lanthanide Complexes of Disulfoxide Ligands with Varied Configurations: Influence of Lanthanide Contraction on the Structures of the Complexes
Authors: Li Jian‐Rong , Zhang Ruo‐Hua , Bu Xian‐He
Published: May 2005

Four new disulfoxide‐LnIII complexes, [Ln(L)2(NO3)3]n {Ln = La (1), n = n; Ln = Gd (2), Dy (3) and Yb (4), n = 2}, have been prepared by the reaction of Ln(NO3)3·nH2O with meso‐1,3‐bis(ethylsulfinyl)propane (meso‐L) in methanol/triethylorthoformate, and their solid‐state structures were characterized by IR spectroscopy, elemental analyses and X‐ray diffraction. Complex 1 is a 1D double‐bridged chain in which the LaIII ions are ten‐coordinate and the L ligands adopt both meso and rac configurations, and a bis‐monodentate bridging coordination mode. While complexes 2–4 have isostructural dinuclear structures, in which the LnIII ions are nine‐coordinate and the ligands show two types of coordination fashions and configurations: bis‐monodentate bridging with a meso‐configuration, and monodentate coordination with a rac‐configuration. The structural differences between 1 and 2–4 indicate the influence of lanthanide contraction on the complex structures. In addition, a change in configuration of the ligand occurs when it reacts with metal ions. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2005)
The 3D Channel Framework Based on Indium(III)–btec, and Its Ion‐Exchange Properties (btec = 1,2,4,5‐Benzenetetracarboxylate)
Authors: Lin Zheng‐zhong , Jiang Fei‐long , Yuan Da‐qiang , Chen Lian , Zhou You‐fu , Hong Mao‐chun
Published: May 2005

Hydrothermal reactions of InCl3 with pyromellitic dianhydride and pyridine derivatives produce three coordination polymers: {(HL)[In3(btec)2(OH)2]·L}n [btec = 1,2,4,5‐benzenetetracarboxylate, L = 2‐picoline (1), L = 4‐picoline (2)] and {(Hdpea)[In3(btec)2(OH)2]}n [dpea = 1,2‐bis(4‐pyridyl)ethane] (3). Single crystal X‐ray diffraction and powder X‐ray diffraction analyses reveal that compounds 1–3 are isostructural and possess the same 3D framework as 1D open channels. Thermal gravimetric studies show that compounds 1–3 are stable up to 300 °C. The guests of the protonated pyridine derivatives located at the channels in 1 and 2 can be fully exchanged by Ca2+ and Ba2+ ions. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2005)
Synthesis and Structure of the First η3‐1,2‐Diphosphaallyl Complexes [(η5‐C5H5)(CO)2M{η3‐RPPC(SiMe3)2}] (M = Mo, R = tBu, Cy; M = W, R = tBu) from [(η5‐C5H5)(CO)2M=P=C(SiMe3)2] (M = Mo, W) and Inversely Polarized Phosphaalkenes RP=C(NMe2)2 (R = tBu, Cy)
Authors: Weber Lothar , Noveski Gabriel , Lassahn Ulrich , Stammler Hans‐Georg , Neumann Beate
Published: May 2005

Reaction of [(η5‐C5H5)(CO)2M=P=C(SiMe3)2] [where M = Mo (2), W (5)] with the phosphaalkene tBuP=C(NMe2)2 (1a) afforded the η3‐1,2‐diphosphaallyl complexes [(η5‐C5H5)(CO)2M{η3‐tBuPPC(SiMe3)2}], [where M = Mo (3a); M = W (6)]. Similarly, 2 and CyP=C(NMe2)2 (1b; where Cy = cyclohexyl) gave rise to the formation of [(η5‐C5H5)(CO)2Mo{CyPPC(SiMe3)2}] (3b) by a phosphinidene transfer process. Small amounts of [{η5‐C5H5)(CO)2Mo}2{η2:η2‐Cy3P5}] (4) were formed as a minor product. However, treatment of 2 and 5 with HP=C(NMe2)2 (1c) yielded the complexes [(η5‐C5H5)(CO)2M{η2‐(Me3Si)2CH–P=P–C(NMe2)2}] [where M = Mo (9), W (10)]. The novel compounds 3a, 3b, 9 and 10 were characterized by means of spectroscopy (IR, 1H, 13C{1H}, 31P{1H} NMR, MS). Moreover, the molecular structures of 3a, 3b, 4, 6 and 10 were determined by X‐ray diffraction analysis. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2005)
Facile Catalytic Decomposition at Low Temperature of Energetic Ionic Liquid as Hydrazine Substitute
Authors: Courthéoux Laurence , Amariei Dan , Rossignol Sylvie , Kappenstein Charles
Published: May 2005

Platinum supported on doped alumina catalysts were prepared and evaluated for the decomposition of NH3OHNO3/water energetic liquid. Powdered and shapedcatalysts remain active after 23 injections at 45 °C. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2005)
Facile and Sensitive Spectrophotometric Determination of Propoxur in Formulations and Environmental Samples
Authors: Kumar Kailasa Suresh , Suvardhan Kanchi , Rekha Dasari , Jayaraj B. , Chiranjeevi Pattium
Published: May 2005

A facile, rapid, and sensitive spectrophotometric method for the determination of propoxur in insecticidal formulations, fortified water, vegetables, agricultural wastewater, and agricultural soil samples has been elaborated. The proposed method is based on the hydrolysis of propoxur under basic conditions, followed by instantaneous azo coupling of the resulting 2‐isopropoxyphenol with the anilines 2a–c. This yielded the orange‐red chromophore 3a (λmax=at 470 nm), the pale‐red coupling product 3b (490 nm), or the red derivative 3c (478 nm), which are stable for 46 h, 38 h, and 24 h, respectively, and could be readily analyzed spectrophotometrically.
Novel, Complex Flavonoids from Mallotus philippensis (Kamala Tree)
Authors: Furusawa Miyuki , Ido Yoshimi , Tanaka Toshiyuki , Ito Tetsuro , Nakaya Ken‐ichi , Ibrahim Iliya , Ohyama Masayoshi , Iinuma Munekazu , Shirataka Yoshiaki , Takahashi Yoshikazu
Published: May 2005

One new flavanone, 4′‐hydroxyisorottlerin (2), and two new chalcone derivatives, kamalachalcones C (3) and D (4), were isolated from Mallotus philippensis (kamala tree). The largest compound (4; Mr 1098 g/mol) was shown to possess a unique, fused‐ring system made of two hydroxy‐chalcone units, giving rise to eight fused benzene/pyran units. From the same plant, the following six known compounds were also isolated: kamalachalcone A (5) and B (6), isoallorottlerin (7), isorottlerin (8), 5,7‐dihydroxy‐8‐methyl‐6‐prenylflavanone (9); 6,6‐dimethylpyrano(2″,3″: 7,6)‐5‐hydroxy‐8‐methylflavanone (10), and rottlerin (1). The structures of the new compounds were confirmed by in‐depth spectral analyses, including 2D‐NMR techniques, and the full 13C‐NMR assignments of the known flavanones 1 and 7–10 are published for the first time.
Chromium‐Mediated Dearomatization: Application to the Synthesis of Racemic 15‐Acetoxytubipofuran and Asymmetric Synthesis of Both Enantiomers
Authors: Kündig E. Peter , Laxmisha Mundruppady S. , Cannas Rita , Tchertchian Sylvie , Ronggang Liu
Published: May 2005

An efficient dearomatization process of [Cr(arene)(CO)3] complexes initiated by a nucleophilic acetaldehyde equivalent is detailed. It generates in a one‐pot reaction three CC bonds and two stereogenic centers. This process allowed a rapid assembly of a cis‐decalin ring system incorporating a homoannular diene unit in just two steps starting from aromatic precursors (Scheme 2). The method was applied to the total synthesis of the eudesmane‐type marine furanosesquiterpene (±)‐15‐acetoxytubipofuran (2). Two routes were successfully used to synthesize the γ‐lactone precursor of the furan ring. The key step in the first approach was a Pd‐catalyzed allylic substitution (Scheme 3), while in the second approach, an Eschenmoser–Claisen rearrangement was highly successful (Scheme 4). The Pd‐catalyzed allylic substitution could be directed to give either the (normal) product with overall retention as major diastereoisomer or the unusual product with inversion of configuration (see Table). For the synthesis of the (−)‐enantiomer (R,R)‐2 of 15‐acetoxytubipofuran, an enantioselective dearomatization in the presence of a chiral diether ligand was implemented (Scheme 7), while the (+)‐enantiomer (S,S)‐2 was obtained via a diastereoselective dearomatization of an arene‐bound chiral imine auxiliary (Scheme 8). Chiroptical data suggest that a revision of the previously assigned absolute configuration of the natural product is required.
Diterpenoid Alkaloids from Aconitum tanguticum
Authors: Wang Yu‐Bo , Huang Rong , Zhang Hong‐Bin , Li Liang
Published: May 2005

A new 19,21‐secohetisan diterpenoid alkaloid, tangutisine B (1), was isolated from the aerial parts of Aconitum tanguticum (Maxim.) Stapf., together with pacidine, 14‐deacetylajadine. The structure of 1 was determined by an interpretation of 1D‐ and 2D‐NMR together with X‐ray crystallographic data. Bioactivities of the isolates were tested in the P‐388, Bel‐7402, Cox‐2, and caspase‐3 assays.
Evidence for Interchange Ligand‐Exchange Processes on Solvated Beryllium Cations
Authors: Puchta Ralph , van Eikema Hommes Nico , van Eldik Rudi
Published: May 2005

The ligand‐exchange mechanism of solvated Be2+ cations has been studied by means of DFT calculations (RB3LYP/6‐311+G**). Ligand exchange around [BeL4]2+, where L=H2O, NH3, CO2, formaldehyde (H2CO), HCN, N2, and CO, was found to follow an associative interchange (Ia) process in all cases. The size of the activation barrier is almost independent of the type of donor atom, and depends mainly on the hybridization undergone by the donor atom. This, in turn, suggests that steric effects play a major role in solvent‐ and ligand‐exchange reactions in Be2+ systems.
Tris(perfluoroalkyl)silyl Entities as Unexpectedly Potent Tags for the Noncovalent Immobilization of Catalysts by Fluorous–Fluorous Interactions: Application to the Synthesis of Several Perfluoro‐Tagged Ligands
Authors: Andrushko Vasyl , Schwinn Dominik , Tzschucke Carl Christoph , Michalek Florian , Horn Joachim , Mössner Christian , Bannwarth Willi
Published: May 2005

Unexpectedly high retention times were obtained in HPLC investigations for compounds equipped with (C8F17CH2CH2)3Si tags on C8F17‐modified silica gel (Fig. 4). Hence, these tags have a high potential for the noncovalent immobilization of catalysts to be applied in organic solvents, allowing for an easy separation and re‐use of the catalyst by filtration and reapplication. The tris(perfluoroalkyl)silyl tag could be incorporated in a straightforward manner into ligands as demonstrated by the synthesis of several prominent classes of ligands (Schemes 4–6).
Facile Syntheses of the Three Major Metabolites of Thioridazine
Authors: Morrow Ryan J. , Millership Jeff S. , Collier Paul S.
Published: May 2005

Efficient, mild syntheses of the three major metabolites 2–4 of the important antipsychotic drug thioridazine (1) have been developed. The cardiotoxic metabolite 2 with a ring sulfoxide moiety was prepared in 96% yield by oxidation of 1 with NaIO4 under acidic conditions. Four different procedures were elaborated for the selective side‐chain sulfide oxidation of 1 to mesoridazine (3), giving rise to yields of up to 91%. Finally, sulforidazine (4) was synthesised via oxidation of the sulfoxide 3 in the presence of either KMnO4 or t‐BuOOH under basic conditions. Except for the oxidation with t‐BuOOH, all reactions took place under mild conditions within a few minutes, were nicely reproducible, and afforded medium‐to‐high yields of the desired products, which could be readily purified by column chromatography.
Secoatisane‐ and Isopimarane‐Type Diterpenoids from the Chinese Mangrove Excoecaria agallocha L.
Authors: Wang Ji‐Dong , Li Zhen‐Yu , Guo Yue‐Wei
Published: May 2005

Phytochemical investigations of the stems and leaves of the Chinese mangrove Excoecaria agallocha L. yielded one new secoatisane‐type diterpenoid, agallochaol C (1), three new isopimarane‐type diterpenoids, agallochaols D–F (2–4), along with four known diterpenoids 5–8. The structures of new compounds 1–4 were determined on the basis of spectroscopic‐data interpretation and chemical evidence.
Polymer‐Supported Ionic‐Liquid‐Catalyzed Synthesis of 1,2,3,4‐Tetrahydro‐ 2‐oxopyrimidine‐5‐carboxylates via Biginelli Reaction
Authors: Wang Zong‐Ting , Wang Shu‐Chao , Xu Li‐Wen
Published: May 2005

The Biginelli reaction between an aromatic aldehyde, ethyl acetoacetate, and urea – catalyzed by polymer‐supported, re‐usable, room‐temperature ionic liquids (RTIL) such as 1b – was shown to efficiently proceed in glacial AcOH at 100° to afford the corresponding pyrimidine‐5‐carboxylates 3 in yields up to 99% within 2 h (Table 2). The catalyst(s) could be reused at least five times, basically without loss of activity, which makes this transformation not only straight‐forward, but also considerably less expensive compared to methods involving classical RTIL catalysts.
Normal cirulant graphs with noncyclic regular subroups
Authors: Marušič Dragan , Morris Joy
Published: May 2005

We prove that any circulant graph of order n with connection set S such that n and the order of ℤ(S), the subgroup of ℤ that fixes S set‐wise, are relatively prime, is also a Cayley graph on some noncyclic group, and shows that the converse does not hold in general. In the special case of normal circulants whose order is not divisible by 4, we classify all such graphs that are also Cayley graphs of a noncyclic group, and show that the noncyclic group must be metacyclic, generated by two cyclic groups whose orders are relatively prime. We construct an infinite family of normal circulants whose order is divisible by 4 that are also normal Cayley graphs on dihedral and noncyclic abelian groups. © 2005 Wiley Periodicals, Inc. J Graph Theory
An improvement of the crossing number bound
Authors: Montaron Bernard
Published: May 2005

The crossing number cr(G) of a simple graph G with n vertices and m edges is the minimum number of edge crossings over all drawings of G on the ℝ2 plane. The conjecture made by Erdős in 1973 that cr(G) ≥ Cm3/n2 was proved in 1982 by Leighton with C = 1/100 and this constant was gradually improved to reach the best known value C = 1/31.08 obtained recently by Pach, Radoicčić, Tardos, and Tóth [4] for graphs such that m ≥ 103n/16. We improve this result with values for the constant in the range 1/31.08 ≤ C &< 1/15 where C depends on m/n2. For example, C > 1/25 for graphs with m/n2 > 0.291 and n > 22, and C > 1/20 for dense graphs with m/n2 ≥ 0.485. © 2005 Wiley Periodicals, Inc. J Graph Theory
13C‐ and 14C‐labelling of N‐[1‐(4‐chlorophenyl)‐1H‐pyrrol‐2‐yl‐methyleneamino] guanidinium acetate
Authors: Almeida Maria , Johannesson Petra , Boman Arne , Lundstedt Torbjörn
Published: May 2005

N‐[1‐(4‐chlorophenyl)‐1H‐pyrrol‐2‐yl‐13C4‐methyleneamino]guanidinium acetate has been synthesized by a four‐step procedure. This involved reduction of the Weinreb amide N,N′‐dimethyl‐N,N′‐dimethyloxybutane‐1,4‐diamide‐1,2,3,4‐13C4 by Dibal‐H to give the corresponding unstable dialdehyde which is reacted in situ with 4‐chloroaniline to form 1‐(4‐chlorophenyl)‐1H‐pyrrole‐13C4. This pyrrole analogue underwent a Vilsmeyer acylation with POCl3/DMF followed by final reaction with aminoguanidine bicarbonate to produce the desired labelled compound with 99% atom 13C. By using DMF [α‐14C] a radio‐labelled analogue was synthesized with a specific activity of 60 mCi/mmol. Copyright © 2005 John Wiley & Sons, Ltd.
Occurrence of heavy metal‐resistance in microflora from serpentine soil of Andaman
Authors: Pal Arundhati , Dutta Suman , Mukherjee P. K. , Paul A. K.
Published: May 2005

Serpentine soils collected from Saddle Hills, Chidyatapu and Rutland of Andaman Islands, India were analyzed for physico‐chemical and microbiological characteristics and compared with those from adjacent non‐serpentine localities. The serpentine soils contained high levels of nickel (1740.0–8033.4 mg/kg dry soil), cobalt (93.2–533.4 mg/kg dry soil) and chromium (302.9–4437.0 mg/kg dry soil), in addition to 62–152 g of iron and 37–60 g of magnesium per kg dry soil. Characteristically the serpentine soils showed low microbial density (6.2–11.3 × 106colony forming unit/g soil) and activity (1.7–3.5 µg fluorescein/g dry soil/h) than non‐serpentine outcrops. Serpentine microbial population was dominated by bacteria which represented 5.12 to 9.5 × 106cfu/g of soil, while the fungal population ranged from 0.17 to 3.21 × 106cfu/g of soil. A total of 342 (200 from serpentine and 142 from non‐serpentine soils) isolates were compared for Ni, Co and Cr resistance. Serpentine microflora was in general, highly resistant than non‐serpentine ones and showed a metal‐resistance profile of Cr > Ni > Co. Amongst the serpentine isolates, 8 and 11 bacteria tolerated >12.0 mMNi and >16.0 mMCr respectively, while 6 fungal isolates showed a minimum inhibitory concentration (MIC) value >8.0 mMCo. These 25 serpentine strains also showed co‐resistance to Cu, Zn and Mn but were sensitive to Hg and Cd. The selected bacterial isolates were resistant to ampicillin, penicillin G and polymyxin B, whereas fungal strains showed resistance to amphotericin B, nystatin and fusidic acid. (© 2005 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Influence of culture conditions on laccase production and isozyme patterns in the white‐rot fungus Trametes gallica
Authors: Dong Jia Li , Zhang Yong Wei , Zhang Ren Huai , Huang Wei Zhao , Zhang Yi Zheng
Published: May 2005

Laccase production by the white‐rot fungus Trametes gallica was studied, using twelve different media under static or shaking condition. The results indicated that organic nitrogen sources such as tryptone and peptone strongly improved laccase production. The application of an amino acid mixture and a lignin preparation also increased the formation of laccase, which was not observed in the presence of potato extract. Native polyacryl amide gel electrophoresis (PAGE) followed by laccase activity staining using guaiacol as the substrate was performed to analyze the laccase isozyme patterns under the different culture conditions employed. Zymograms revealed a total of twenty different laccase activity bands that appeared in individual patterns, dependent on the respective culture condition applied. This indicates that both the medium composition and the mode of incubation (static or shaking) influenced the laccase isozyme gene expression. This was the first time to report so many laccase isozymes in a fungus. Native PAGE with silver staining showed that laccases were the main protein productions in several media providing a potentially convenient way in purifying laccases from T. gallica. (© 2005 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Fungal endophytes in five medicinal plant species from Kudremukh Range, Western Ghats of India
Authors: Raviraja N. S.
Published: May 2005

Eighteen species of endophytic fungi were isolated from bark, stem and leaf segments of five medicinal plant species growing within the Kudremukh range in the Western Ghats of India. The dominant endophytic fungal species isolated from these plant species were Curvularia clavata, C. lunata, C. pallescens and Fusarium oxysporum. The highest species richness as well as frequency of colonization of endophytic fungi was found in the leaf segments, rather than the stem and bark segments, of the host plant species. The greatest number of endophytic fungal species were found within Callicarpa tomentosa (11 species), whereas Lobelia nicotinifolia harbored the lowest number of fungal endophytes (5 species). This study provides evidence that fungal endophytes are host and tissue specific. (© 2005 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Tannic acid resistance in ruminal streptococcal isolates
Authors: Goel Gunjan , Puniya Anil Kumar , Singh Kishan
Published: May 2005

Tannin degrading isolates of Streptococcus spp. from rumen of non‐adaptive cattle, when grown in BHI broth, were able to tolerate tannic acid upto a level of 50 g/l. An increase in lag period from 1.5 to 6 h was observed for the isolates in presence of increased concentration of tannic acid. In addition, the morphology of gram positive diplococci converted to an elongated chain of 40–50 cells with increasing tannic acid from 1 to 4%. Qualitatively, the tannase activity was found to be present in the isolates tested, indicating their potential of being a tannin degrader. (© 2005 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Experimental study of a high-power CW diode-side-pumped Nd:YAG rod laser
Authors: Hajiesmaeilbaigi F , Razzaghi H , Esfahani M M , Moghaddam M R A , Sabbaghzadeh J
Published: May 2005

In this paper we report on the characterization of a diode-side-pumped Nd:YAG rod laser operating at 300 W CW output power. The simulated and measured pump energy distributions in the crystal are compared. The thermal lens effect of the Nd:YAG have been experimentally investigated, and its influence on the performance of the laser are discussed. Output power and the beam quality of the laser under different resonator mirrors and rod end-face curvatures have been experimentally studied. The optical-to-optical and electrical-to-optical efficiencies are 28.5% and 11%, respectively. The beam parameter product is 40 mm⋅mrad and the instability of laser is about 3%.
Epoxies Modified by Palmitic Acid: From Hot‐Melt Adhesives to Plasticized Networks
Authors: Hoppe Cristina E. , Galante María J. , Oyanguren Patricia A. , Williams Roberto J. J.
Published: May 2005

Summary: Reactions taking place in a homogeneous solution of an epoxy monomer based on the diglycidyl ether of bisphenol A (DGEBA) and palmitic acid (PA), in the presence of benzyldimethylamine (BDMA), were investigated using Fourier‐transformed infrared spectroscopy (FTIR) and size exclusion chromatography (SEC). In the stoichiometric formulations prepared with equal molar ratios of epoxy (E) to carboxyl groups, E/PA = 1, the main reaction was the carboxyl addition to the epoxy giving a β‐hydroxy ester. This reaction was followed by transesterification that occurred to a very small extent. In the formulations prepared with an epoxy excess, E/PA > 1, the transesterification reactions were very significant as well as the homopolymerization of the epoxy excess that took place to an almost complete conversion. Reaction products synthesized in the range of 1 < E/PA < 2 were solids at room temperature due to the crystallization of a fraction of fatty acid chains. Above the melting temperature, reaction products recovered the liquid state. The formulation synthesized with E/PA = 2 exhibited a good behavior as a hot‐melt adhesive of steel sheets with a single lap‐shear strength of 2.5 MPa and an interfacial‐cohesive failure. For E/PA > 3, the gelation took place leading to the networks exhibiting a single glass transition temperature (Tg) without any evidence of crystallization or phase separation. Tg varied from 90 °C for the neat epoxy to 0 °C for the formulation with E/PA = 3.

Single lap‐shear strength values of hot‐melt adhesives corresponding to reaction products synthesized with E/PA = 1.6, 1.8, and 2.

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Single lap‐shear strength values of hot‐melt adhesives corresponding to reaction products synthesized with E/PA = 1.6, 1.8, and 2.
Some design criteria for UWB planar monopole antennas: Application to a slotted rectangular monopole
Authors: Valderas D. , Meléndez J. , Sancho I.
Published: May 2005

A method to increase the bandwidth of planar monopoles is presented. Following the provided design criteria, a simple rectangular‐shaped monopole is fit to operate at ultra‐wide‐band (UWB) frequency. The process involves two steps: (i) optimizing the perimeter and feeding dimensions and (ii) conducting a suitable slot. This causes the difference between the upper and lower frequency limits to nearly double. The exhibited bandwidth ratio is 1:3.75. The measured radiation patterns are presented and observed to be stable. © 2005 Wiley Periodicals, Inc. Microwave Opt Technol Lett 46: 6–11, 2005; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.20885
A slotted strip as a key element of the simplest notch and bandstop filters
Authors: Kirilenko Anatoly A. , Mospan Lyudmyla P.
Published: May 2005

In this paper, a new notch and bandstop filters are proposed and investigated. A rejection section, based on a thin slotted H‐plane strip, provides a symmetric frequency response with very low insertion loss out of the stopband. The rejection phenomenon is explained by the simultaneous excitation of two eigenoscillations with low and highQ‐factors. The results of numerical design and measurement data are given for a 3% notch filter and a 2% three‐section bandstop one. Such a notch filter is probably the simplest one due to its easy fabrication and has the potential to be incorporated in a waveguide circuit by placing it between the waveguide flanges. © 2005 Wiley Periodicals, Inc. Microwave Opt Technol Lett 46: 20–24, 2005; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.20889
Large antenna array remoting using radio‐over‐fiber techniques for radio astronomical application
Authors: Montebugnoli S. , Boschi M. , Perini F. , Faccin P. , Brunori G. , Pirazzini E.
Published: May 2005

A field‐trial system is presented in this paper to demonstrate that radio‐over‐fiber (RoF) techniques can be successfully applied to the remoting of a large antenna array for radio astronomical applications. © 2005 Wiley Periodicals, Inc. Microwave Opt Technol Lett 46: 48–54, 2005; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.20898
Printed short‐circuited wideband monopole antenna with band‐notched operation
Authors: Wong Kin‐Lu , Chou Liang‐Che , Chang Fa‐Shian
Published: May 2005

This paper presents the band‐notched operation of a printed short‐circuited wideband monopole antenna. The notched or rejected band within a wide operating bandwidth is obtained by embedding an inverted U‐shaped slot close to the shorting point of the antenna, where strong excited surface currents in the antenna are usually present. The notched band is controllable by adjusting the lengths of the inner and outer perimeters of the embedded U‐shaped slot. A constructed prototype of the antenna is demonstrated, and a parametric study of the embedded slot used for band‐notched operation is also presented. © 2005 Wiley Periodicals, Inc. Microwave Opt Technol Lett 46: 58–61, 2005; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.20900
Microwave dielectric properties of polybutylene terephtalate (PBT) with carbon black particles
Authors: Costa L. C. , Devesa S. , André P. , Henry F.
Published: May 2005

The synthesis of composites based on polymers containing carbon as additives is rather relevant because it has been found that applications in several industries are increasing, particularly due to their unusual mechanical and electrical properties. By choosing the adequate doping concentrations, we can precisely control the electrical properties in the microwave frequencies, in order to tailor the desired behavior. In this study, we present the results of the complex‐permittivity measurements, ϵ* = ϵ′ − í ϵ″, at 2.7, 5, and 12.8 GHz, on polybutylene terephtalate (PBT), with different concentration of black carbon particles, using the resonant‐cavity method. Measuring the shift in the resonant frequency of the cavity, Δf, caused by the insertion of the sample, we can calculate to the real part of the complex permittivity, ϵ′, while the measure of the change in the inverse of the quality factor of the cavity, Δ(1/Q), allow us to calculate the imaginary part, ϵ″. Maxwell–Wagner–Sillars (MWS) and Looyenga mixture laws are applied to the obtained results. © 2005 Wiley Periodicals, Inc. Microwave Opt Technol Lett 46: 61–63, 2005; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.20901
A 5‐GHz injection‐locked phase‐locked loop
Authors: Plessas Fotis , Kalivas Grigorios
Published: May 2005

In this paper, we introduce a 5‐GHz injection‐locked phase‐locked loop (ILPLL). A new method is presented for accurate analysis of the phase‐noise performance of the proposed system. Furthermore, comparison with other phase‐noise‐estimation techniques demonstrates that our method provides an accurate characterization of any ILPLL topology. The theoretical and calculation results show an improved performance for phase noise, locking range, and power consumption compared to conventional phase‐locked loops (PLLs) and injection‐locked oscillators (ILOs). Furthermore, we demonstrate the pulling behavior of the injected oscillator and examine the obtained results. To verify the presented analysis, a 5‐GHz prototype has been implemented, which achieves −119‐dBc/Hz at 100‐KHz frequency offset, producing +4.5 dBm of output power and consuming 9 mA at 3 V. © 2005 Wiley Periodicals, Inc. Microwave Opt Technol Lett 46: 80–84, 2005; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.20907
InGaP/GaAs HBT power amplifier with CMRC structure
Authors: Poek C. K. , Yan B. P. , Yang E. S.
Published: May 2005

An InGaP/GaAs heterojunction bipolar transistor (HBT) power amplifier is developed for WCDMA user equipment, specifically, band‐1‐power class‐2 application. The HBT power amplifier demonstrates maximum output power Poutof 29.4 dBm and power‐added efficiency (PAE) of 48% at a frequency of 1.95 GHz. When operated according to the WCDMA standard, it achieves Poutof 27 dBm and PAE of 32.4%. The adjacent channel leakage power ratio (ACLR) is −33 dBc. A compact microstrip resonant cell (CMRC) circuit is implemented on the HBT amplifier in order to further improve the PAE, ACLR, and IM3 performances. This results in improvements of 8 dB and 6% for the ACLR and PAE, respectively. © 2005 Wiley Periodicals, Inc. Microwave Opt Technol Lett 46: 84–88, 2005; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.20908
Two‐stage S‐band erbium‐doped fiber amplifier using a depressed‐cladding fiber
Authors: Harun S. W. , Saat N. K. , Ahmad H.
Published: May 2005

A two‐stage short‐wavelength‐band erbium‐doped fiber amplifier (S‐band EDFA) is demonstrated using a depressed‐cladding erbium‐doped fiber (EDF). The EDF has a fundamental‐mode cutoff wavelength of about 1525 nm in order to suppress amplified spontaneous emission at the longer wavelength. The highest gain curve is obtained by setting the first‐ and second‐stage pumps at 85 and 190 mW, respectively, where the unsaturated gains are obtained at about 28 dB. The gain was limited by the 12‐dBm saturation power of the amplifier. The unsaturated noise figure ranged from 8.5 to 9.3 dB for all pump combinations tested. © 2005 Wiley Periodicals, Inc. Microwave Opt Technol Lett 46: 92–94, 2005; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.20910
Skeletal muscle involvement in human immunodeficiency virus (HIV)–infected patients in the era of highly active antiretroviral therapy (HAART)
Authors: Authier François‐Jérôme , Chariot Patrick , Gherardi Romain K.
Published: May 2005

Skeletal muscle involvement can occur at all stages of human immunodeficiency virus (HIV) infection, and may represent the first manifestation of the disease. Myopathies in HIV‐infected patients are classified as follows: (1) HIV‐associated myopathies and related conditions, including HIV polymyositis, inclusion‐body myositis, nemaline myopathy, diffuse infiltrative lymphocytosis syndrome (DILS), HIV‐wasting syndrome, vasculitic processes, myasthenic syndromes, and chronic fatigue; (2) muscle complications of antiretroviral therapy, including zidovudine and toxic mitochondrial myopathies related to other nucleoside‐analogue reverse‐transcriptase inhibitors (NRTIs), HIV‐associated lipodystrophy syndrome, and immune restoration syndrome related to highly active antiretroviral therapy (HAART); (3) opportunistic infections and tumor infiltrations of skeletal muscle; and (4) rhabdomyolysis. Introduction of HAART has dramatically modified the natural history of HIV disease by controlling viral replication, but, in turn, lengthening of the survival of HIV‐infected individuals has been associated with an increasing prevalence of iatrogenic conditions. Muscle Nerve, 2005
Compatibilizer‐induced microstructural changes in poly(trimethylene terephthalate)/EPDM blends studied by the positron annihilation lifetime technique and differential scanning calorimetry
Authors: Ravikumar HB , Ranganathaiah C
Published: May 2005

Blends of poly(trimethylene terephthalate) (PTT) and ethylene propylene diene monomer (EPDM) with and without the compatibilizer poly (EPM‐graft‐MA) were investigated by positron annihilation lifetime spectroscopy (PALS) and differential scanning calorimetric (DSC) measurements. The DSC results for the blend with 50/50 composition revealed two glass transition temperatures, indicating a two‐phase system. In the presence of compatibilizer, the two glass transition temperatures shifts towards each other, suggesting an increased interaction between the blend components. The PALS results for the blends without compatibilizer showed an increase in free volume hole size and concentration with increasing EPDM content in the blend, suggesting the coalescence of free volumes of EPDM with the PTT to some extent, but the phase‐separation behaviour continued. The free volume of these blends exhibited positive deviation from the known free volume linear additivity rule. However, poly(EPM‐graft‐MA) compatibilized blends of PTT/EPDM had a noticeable decrease in the free volume parameters, which was clearly due to the compatibilizing effect through increased interaction between blend components. Copyright © 2005 Society of Chemical Industry
Markovian approach of the electron localization functions
Authors: Putz Mihai V.
Published: May 2005

By combining the path integral description of Markovian processes in terms of conditional probabilities with the catastrophe topological concepts alternative electron localization classes of functions (ELFs) are formulated, consistent with the Heisenberg and Pauli principles, complementing and augmenting the previous work of Becke and Edgecombe. © 2005 Wiley Periodicals, Inc. Int J Quantum Chem, 2005
Analytical second derivatives in the Amsterdam density functional package
Authors: Wolff Stephen K.
Published: May 2005

Recently, analytical second derivatives with respect to nuclear coordinates have been implemented in the Amsterdam density functional (ADF) package. This article presents the detailed formalism of that implementation. Calculations on small molecules such as methane show good agreement between the analytical and numerical frequencies. Calculations on benzene and larger molecules show that the analytical second derivatives code is 2 to 3 times faster than the numerical. © 2005 Wiley Periodicals, Inc. Int J Quantum Chem, 2005
Using probabilistic model checking for dynamic power management
Authors: Norman Gethin , Parker David , Kwiatkowska Marta , Shukla Sandeep , Gupta Rajesh
Published: May 2005

Dynamic power management (DPM) refers to the use of runtime strategies in order to achieve a tradeoff between the performance and power consumption of a system and its components. We present an approach to analysing stochastic DPM strategies using probabilistic model checking as the formal framework. This is a novel application of probabilistic model checking to the area of system design. This approach allows us to obtain performance measures of strategies by automated analytical means without expensive simulations. Moreover, one can formally establish various probabilistically quantified properties pertaining to buffer sizes, delays, energy usage etc., for each derived strategy.
Social and psychological characteristics of Greek secondary school students with learning difficulties
Authors: Zafiriadis Kiriakos , Livaditis Miltos , Xenitidis Kiriakos , Diamanti Miranta , Tsatalmpasidou Evgenia , Sigalas Ioannis , Polemikos Nikitas
Published: May 2005

In Greece there is an almost total lack of special education after the primary school (6th grade). This is a descriptive study that aimed to examine social, academic and psychological characteristics of secondary school students with a history of special placement during primary school. It compared 86 students with a placement (group A) with their 1284 schoolmates with no such placement history (group B) with respect to scores on School Adjustment Scale, Academic Motivation Self‐Rating Inventory and Youth Self‐Report. Group A presented more family social, academic and psychological problems such as: One‐parent family, lower socioeconomic status, poor adjustment, low motivation and (especially for boys) high internalizing and externalizing scores. The high rates of failure and dropout of these students indicate that in Greece there is a need to set up appropriate services to help secondary school students with learning difficulties.
Patient's Education by Nurse: What We Really do Achieve?
Authors: González Beatriz , Lupón Josep , Herreros Joan , Urrutia Agustín , Altimir Salvador , Coll Ramon , Prats Montserrat , Valle Vicente
Published: May 2005

Aim: To evaluate what is really achieved with nurse education in an outpatient heart failure population.

Method: The answers obtained in a nurse questionnaire performed at the first visit to the Unit and at 1 year of follow-up were compared. The questionnaire was addressed to know how compliant patients were and how much they knew about their disease and their treatment.

Results: Two hundred and ninety eight patients (219 men and 79 women) were evaluated. Baseline mean age was 65 years (35–86). At first visit only 30% knew and understood the performance of the heart; 56% at 1 year ( p < 0.001). Only 28% initially understood the disease; 55% at follow-up ( p < 0.001). Awareness of more than 3 worsening signs increased from 66.5% to 86.5% ( p < 0.001). Knowledge of the names of all the pills they were receiving increased from 33% to 44% ( p < 0.001), of the action of these pills from 24% to 44% ( p < 0.001), and of how to use nitroglycerine among patients with ischemic heart disease from 87% to 96% ( p < 0.001). Initially 63% monitored their weight only at the medical visit and 21% monitored it at least once a week; at 1 year these percentages were 16% and 39% respectively ( p < 0.001). At baseline 45% checked blood pressure only at the medical visit and 28.5% checked it at least once a week; at 1 year these percentages were 12% and 43% ( p < 0.001). Whereas no significant differences were found in sodium restricted diet compliance, exercise performance increased slightly although statistically significantly ( p = 0.01). The great majority of patients never or only very rarely smoked or drunk alcoholic beverages, both at first visit and at 1 year, although both habits increased slightly during follow-up. No significant differences in treatment compliance (92% vs. 88% were taking all the medications prescribed) were found.

Conclusion: Nurse-guided education has changed self-care behaviour of patients with heart failure in several important aspects, as weight and blood monitoring, and has increased their knowledge and understanding of the disease and treatment. However, these improvements have not been reflected in a better compliance of treatment and sodium restricted diet. Such aspects need more and more work to obtain better results.
RNA interference induced by siRNAs modified with 4′‐thioribonucleosides in cultured mammalian cells
Authors: Hoshika Shuichi , Minakawa Noriaki , Kamiya Hiroyuki , Harashima Hideyoshi , Matsuda Akira
Published: May 2005

Short interfering RNAs (siRNAs) variously modified with 4′‐thioribonucleosides against the Photinus luciferase gene were tested for their induction of the RNA interference (RNAi) activity in cultured NIH/3T3 cells. Results indicated that modifications at the sense‐strand were well tolerated for RNAi activity except for full modification with 4′‐thioribonucleosides. However, the activity of siRNAs modified at the antisense‐strand was dependent on the position and the number of modifications with 4′‐thioribonucleosides. Since modifications of siRNAs with 4′‐thioribonucleosides were well tolerated in RNAi activity compared with that of 2′‐O‐methyl nucleosides, 4′‐thioribonucleosides might be potentially useful in the development of novel and effective chemically modified siRNAs.
Regime type and politics in Ukraine under Kuchma
Authors: Kuzio Taras
Published: May 2005

The article surveys and discusses different definitions of regime type in Ukraine and whether they provide a sound understanding of the regime emerging in Ukraine and other CIS states since the late 1990s. Ukraine and the CIS witnessed democratic regression and therefore could not be assumed that they were on a ‘transition’ path to a consolidated democracy. The majority of CIS states have either already moved to fully authoritarian regimes, such as Russia. Or, like Ukraine, they remained as unstable competitive authoritarian regimes which exhibited a ‘hybrid’ fusion of the former Soviet system and the emerging reformed economy and polity. Ukraine’s oligarchs during Kuchma’s second term preferred a fully authoritarian regime but they were also divided among themselves and faced a formidable opposition. These factors blocked the creation of a fully authoritarian regime under Kuchma and led to the victory of the opposition through Ukraine’s Orange Revolution.
CALL: past, present and future — a bibliometric approach
Authors: JUNG UDO O. H.
Published: May 2005

A bibliometric approach is used not only to sketch out the development of CALL during the last 25 years,
but also to assess the contribution of educational technology to 21st century foreign-language teaching and learning. This study
is based on the six instalments of the author’s International (and multilingual) Bibliography of Computer Assisted Language
Learning and the 5,301 entries contained therein. The once text-based bibliography has been transformed into a searchable database.
Since index terms to describe both the contents and the nature of individual publications have been attached to the bibliographic
data, it is now possible to query whether the 25,000 descriptors cluster around certain topics and to depict developments
chronologically. The statistical evaluation of a large corpus also avoids the pitfalls of selective interpretation. Recent
controversies about the chronologisation of CALL events as well as the internal consistency of such time chunks are addressed.
The data suggest that the online/offline divide occurs around 1993 and that
the latest additions to the foreign language teacher’s tool box –
from e-mails to voicechats – overcome the language
acquisition/language learning barrier. New and student-oriented forms of dealing with foreign language learning come to the
fore. This has induced some researchers to concentrate on events where conversation breaks down, because learners must then ask
for modified input or negotiate the meanings of lexical items. Such a strategy promises success in instructed second-language
acquisition. It is suggested, however, that the foreign language
teacher’s intervention is a necessary complement to second-language developmental processes. Educational technology may
allow the teacher to let nature run its course nowadays. But when nature is unsympathetic to the cause of foreign language
learning the teacher must rein in the student’s language acquisition device to protect him or her from certain sanctions
the target community holds in store for the unsuccessful learner.
Inspectable learner reports for web-based language learning
Authors: HEIFT TRUDE
Published: May 2005

In this paper we present the Report Manager of our Web-based
tutoring system for German – an interface to a persistent learner report that students can inspect and manipulate.
The learner report collects and retains information on the learner’s progress and performance that is saved between visits.
It also provides access to a journaling system that records prior inputs along with detailed error analysis, and a bookmarking system
that tracks exercise completion. Finally, results can be printed or emailed to an instructor. In the Fall semester 2003,
we conducted a study with 87 learners of German to investigate how their study habits are affected by an inspectable learner report.
Our study indicates that students reviewed their learner profiles frequently
– 33 times on average over the course of a semester – and that 70% of the students repeated exercises after having
inspected their learner profile. So, while detailed user profiles and performance tracking are invaluable tools for CALL researchers,
our study suggests that students also utilize and are influenced by the information.