bluuebunny/crossref_metadata_2025_split huggingface dataset:
Unconventional ventral attachment of time–depth recorders as a new method for investigating time budget and diving behaviour of seabirds
Authors: Tremblay Yann , Cherel Yves , Oremus Marc , Tveraa Torkild , Chastel Olivier 
Published: May 2003

SUMMARYWe tested the use of commercially available electronic time–depth recorders (TDRs) to quantify activities and thus total time budgets of seabirds. This new method involved first fitting TDRs onto the birds' bellies(not on their backs), and, secondly, analysing continuous recordings of temperature, light and pressure to differentiate activities on land and at sea. The birds studied were 12 common guillemots Uria aalge rearing chicks at Hornøya, in northern Norway. The method successfully recorded five different activities: at the colony, flying, diving, and resting or active at the sea surface. Overall, common guillemots spent 68% of their time at the colony and 32% at sea. While at sea, the birds spent the majority (77%)of their time at the surface, during which they were active 64% of the time,and rested only 13%. Birds engaged in the costly behaviours of flying and diving for shorter times (11% and 12% of their time at sea, respectively). The method allowed us to differentiate between two types of trips to sea based on the presence (foraging trips: 77% of the total number of trips) or absence(non-foraging trips: 23%) of dives. On average, foraging trips lasted 3.2 h,but most trips were shorter (&lt;1 h), during which the mean estimated travel distance from the colony was 11 km. Diving occurred in bouts of 7.7±6.6 dives (mean ± S.D.). The mean maximum dive depth was 10.2±7.6 m(deepest dive: 37 m), and the mean dive duration and post-dive intervals were 38.7±21.3 s (longest dive: 119 s) and 20±12 s, respectively. Direct and indirect evidence suggests that common guillemots had no difficulty in finding food during the study period, and that the TDRs had minimal effects on the birds' behaviour and physiology. The method is easy to use in the field and is applicable to many other flying seabird species; it is therefore an efficient way of collecting information on time budgets and diving behaviour in the context of various ecological and monitoring studies.
The role of visual landmarks in the avian familiar area map
Authors: Holland Richard A. 
Published: May 2003

SUMMARYThe question of whether homing pigeons use visual landmarks for orientation from distant, familiar sites is an unresolved issue in the field of avian navigation. Where evidence has been found, the question still remains as to whether the landmarks are used independent of the map and compass mechanism for orientation that is so important to birds. Recent research has challenged the extent to which experiments that do not directly manipulate the visual sense can be used as evidence for compass-independent orientation. However, it is proposed that extending a new technique for research on vision in homing to include manipulation of the compasses used by birds might be able to resolve this issue. The effect of the structure of the visual sense of the homing pigeon on its use of visual landmarks is also considered.
Metabolic and ionic responses of trout hepatocytes to anisosmotic exposure
Authors: Krumschnabel Gerhard , Gstir Ronald , Manzl Claudia , Prem Caroline , Pafundo Diego , Schwarzbaum Pablo J. 
Published: May 2003

SUMMARYTrout hepatocytes exposed to hypo- or hyperosmotic conditions respond by swelling and shrinking, respectively, followed by regulatory volume changes that almost, although not completely, restore cell volume. These anisosmotic conditions have a significant impact on metabolic functions. In hyposmotic medium, oxygen consumption(V̇O2) and glucose production rates were significantly reduced, whereas lactate accumulation was not significantly affected. By contrast, hyperosmotic conditions did not affect V̇O2 and lactate production but caused a sustained reduction in glucose production. Volume changes were also accompanied by alterations in intracellular free calcium ([Ca2+]i). At the cell population level,hyposmotic exposure evoked a moderate and slowly developing increase in[Ca2+]i, whereas hyperosmolarity caused a pronounced and sustained increase, which peaked at the time of maximum cell shrinkage but clearly exceeded a mere concentration effect due to volume reduction. Responses of individual cells were highly variable in hyposmotic medium, with only 60% showing a clear increase in [Ca2+]i, while in hyperosmotic conditions all cells displayed elevated[Ca2+]i levels. A decrease in intracellular pH (pHi)observed in hyposmotic medium was insensitive to EIPA, an inhibitor of Na+/H+ exchange, and SITS, an inhibitor of Cl–/HCO3– exchange, but was prevented in Cl–-free medium. In hyperosmotic medium, pHi increased. This alkalinization did not occur under conditions of blocked Na+/H+ exchange and was significantly diminished upon inhibition of Cl–/HCO3– exchange,suggesting an important role of these ion transporters in regulatory volume increase of trout hepatocytes.
Stimulation of JH biosynthesis by the corpora allata of adult female Aedes aegypti in vitro: effect of farnesoic acid and Aedesallatotropin
Authors: Li Yiping , Unnithan Gopalan C. , Veenstra Jan A. , Feyereisen René , Noriega Fernando G. 
Published: May 2003

SUMMARY
Previous studies have demonstrated that the synthesis of juvenile hormone(JH) by the isolated corpora allata (CA) complex in vitro as well as the JH titer in the yellow fever mosquito Aedes aegypti are elevated before feeding and low after a blood meal. In the present study, we used an in vitro radiochemical assay to analyze the effect of farnesoic acid(FA) and Aedes allatotropin (Aedes-AT) on the biosynthesis of JH and methyl farnesoate (MF) by the isolated CA complex of A. aegypti adult female. CA complex from day-0 females (0–1 h after emergence) exhibited a low basal juvenile hormone III (JH III) biosynthetic activity and did not respond to either allatotropic or FA stimulation. However, incubation of CA complexes from newly emerged females with Aedes-AT plus FA resulted in very high production of JH III. This is the first report suggesting that allatotropin makes corpora allata in newly emerged females capable for JH biosynthesis. When we studied CA complexes dissected from females 1 day after emergence, the stimulatory action of Aedes-AT was strong and dose-dependent,with maximum stimulation in the range of 10–8–10–9 mol l–1,suggesting that Aedes-AT is indeed a true allatotropin (a molecule with allatotropic activity) in A. aegypti. The addition to the culture medium of 40 μmol l–1 FA, a JH precursor, resulted in a 9-fold increase in JH III biosynthesis in 2-, 4- and 6-day-old sugar-fed females. The two major labeled products synthesized by the stimulated CA complex were identified as JH III and MF by RP-HPLC and GC–MS. Treatment of CA complexes with FA, but not Aedes-AT, resulted in an increase in MF. Application of both Aedes-AT and FA to the CA complexes of 2-, 4- and 6-day-old females resulted in the same effects as FA alone. These data suggest that in sugar-fed females, FA and Aedes-AT exert different effects on the terminal steps in JH biosynthesis.
Distribution and serotonin-induced activation of vacuolar-type H+-ATPase in the salivary glands of the blowflyCalliphora vicina
Authors: Zimmermann Bernhard , Dames Petra , Walz Bernd , Baumann Otto 
Published: May 2003

SUMMARYSecretory activity in blowfly salivary glands is activated by the hormone serotonin. We have investigated the distribution and activity of two cation pumps that are possibly involved with transepithelial ion transport, i.e. Na+/K+-ATPase and vacuolar-type H+-ATPase(V-ATPase). By immunofluorescence labelling of secretory cells,Na+/K+-ATPase was localized on the basolateral plasma membrane and V-ATPase on the highly folded apical membrane. Activities of both ATPases were probed in salivary gland homogenates by applying specific inhibitors for these ion pumps, namely ouabain and bafilomycin A1. In control glands, bafilomycin-A1-sensitive V-ATPase activity and ouabain-sensitive Na+/K+-ATPase activity accounted for 36% and 19%, respectively, of the total ATPase activity. V-ATPase activity increased approximately twofold after stimulation with serotonin, whereas Na+/K+-ATPase activity was not significantly affected. Biochemical assays provided evidence that the serotonin-induced activation of V-ATPase activity was accompanied by a recruitment of peripheral V1subunits from the cytosol to the plasma membrane, indicative of the assembly of V0V1 holoenzymes.These data show that a V-ATPase located in the apical plasma membranes of the secretory cells is a component of the apical `potassium pump' that has been identified previously by physiological approaches. The V-ATPase energizes the apical membrane and provides the primary driving force for fuelling a putative K+/nH+ antiporter and, thus, for fluid secretion. Serotonin-induced assembly of V0V1holoenzymes might constitute a regulatory mechanism for the control of pump activity.
A [3+2]-Photocycloaddition of 9,10-Dicyanophenanthrene to 1,3-Butadiene
Authors: Kubo Yasuo , Kusumoto Kouhei , Nakajima Satoshi , Inamura Isamu 
Published: May 2003

Abstract
In the photoreactions of 9,10-dicyanophenanthrene (6) with 1,3-butadiene (7) a novel [3+2]-photocycloaddition at the 9,10-position of the phenanthrene ring of 6 to one of the double bond of 7 and a [2+2]-cycloaddition at the 9,10-position of 6 were found to proceed from the singlet and the triplet excited states of 6, respectively.
Monitoring of Hydrothermal Reactions in 3 ms Using Fused-Silica Capillary Tubing
Authors: Kawamura Kunio 
Published: May 2003

Abstract
Monitoring of hydrothermal reactions in the time range of 3 - 1000 ms was succeeded by flow reactor using fused-silica capillary tubing. The technique was applied for measuring the hydrolysis rate of ATP at 250 °C in which the minimum monitoring time was 3.1 ms. The rate constants of ATP hydrolysis was consistent with that was extrapolated of the Arrhenius plots in our previous study. This method enables milli-second monitoring of hydrothermal reactions.
Construction of a Multiple Porphyrin System Using a de novo Designed Peptide Porphyrin and Hemin
Authors: Ushiyama Masato , Arisaka Fumio , Yamamura Takeshi 
Published: May 2003

Abstract
Multiple porphyrin systems were constructed using a Zn(II) porphyrin, A, which is a de novo designed peptide porphyrin, and Fe(III) protoporphyrin IX chloride, B. A forms a dimer in buffer solution containing 2,2,2-trifluoroethanol. However, A forms a trimer by incorporating three equivalents of B per A. The results suggest that the A/B solution achieves a 12-porphyrin system consisting of different kinds of metalloporphyrins.
Unusual Oxidation Reaction of an Overcrowded Thiagermacyclohexene Derivative
Authors: Tokitoh Norihiro , El-Sayed Ibrahim El-Tantawy , Okazaki Renji 
Published: May 2003

Abstract
Oxidation of extremely overcrowded 1,2-thiagermacyclohex-4-ene derivatives with m-chloroperbenzoic acid resulted in competitive formation of the ring expanded 1,2,7-oxathiagermacyclohept-4-ene derivatives and the ring contracted 1,2,3-oxathiagermacyclopentane derivatives. The latter reaction products are found to isomerize into the former ones very slowly at room temperature not only in solution but also in the crystalline state.
The Formation of a Hydrogencarbonato-bridged Dinuclear Copper(II) Complex by Fixation and Activation of Atmospheric CO2
Authors: Nishida Yasuko , Yatani Akihiro , Nakao Yasuo , Taka Jyun-ichiro , Kashino Setsuo , Mori Wasuke , Suzuki Shinnichiro 
Published: May 2003

Abstract
The first hydrogencarbonato-bridged dinuclear copper(II) complex [Cu2(L)(HCO3)](BF4)2·5H2O, 1 was obtained by allowing of acetone solution containing a copper(II) complex [Cu2(L)(OH)](BF4)2·6H2O, where HL is N,N,N′,N′-tetrakis[(1-methyl-2-benzimidazolyl)methyl]-2-hydroxy-1,3-diaminopropane. The crystal structure of 1 was determined by X-ray crystallography and characterized by the magnetic susceptibility and infrared and visible absorption spectrum.
Inhibition of 2,7-Dideoxy-7-fluoro-2,3-didehydrosialic Acid for Binding of Influenza Virus H1 Hemagglutinin to GM3
Authors: Sate Toshinori , Ohtake Fuyuka , Ohira Yutaka , Okahata Yoshio 
Published: May 2003

Abstract
A sialidase inhibitor, 2,7-dideoxy-7-fluoro-2,3-didehydrosialic acid was found to effectively inhibit the binding of influenza virus H1 hemagglutinin to ganglioside GM3.
Hydrogen Evolution from Glucose with the Combination of Glucose Dehydrogenase and Hydrogenase from A. eutrophus H16
Authors: Inoue Tomoyuki , Kumar Shrestha Niranjan , Kamachi Toshiaki , Okura Ichiro 
Published: May 2003

Abstract
Hydrogen production system from glucose consisting of glucose dehydrogenase from Bacillus sp. and hydrogenase from Alcaligenes eutrophus H16 was established. When the solution containing glucose, glucose dehydrogenase, NAD, and hydrogenase was incubated at 30 °C, hydrogen evolution was observed.
First Observation That Electroinactively Bound Cations in Clay Can Participate in Electrocatalytic Reaction
Authors: Ilangovan G , Zen J-M 
Published: May 2003

Abstract
The electrocatalytic oxidation of guanine by nontronite-bound electroinactive Fe(bpy)32+ has been identified with a catalytic rate constant of 5.84 × 104 M s−1.
Reductive Degradation of a [2Fe-2S] Cluster of Chlorella Ferredoxin Studied by Circular Dichroism Spectroscopy
Authors: Nishiyama Katsuhiko , Yamashita Ryu , Ishida Makoto , Taniguchi Isao 
Published: May 2003

Abstract
Chlorella ferredoxin is thermostable for several hours at 50 °C. However, in the presence of 9,10-phenanthrorine or 2,2′-bipyridine, the oxidized [2Fe-2S] cluster of ferredoxin undergoes spontaneous reduction to the reduced state without adding other reducing agents.
Synthesis and Spectral Properties of Novel Si-Ru-Ru-Si-C6H4 Polymers
Authors: Nombel Paul , Hatanaka Yasuo , Shimada Shigeru , Tanaka Masato 
Published: May 2003

Abstract
Dehydrogenative coupling reactions of bis(hydrosilyl)benzenes with [Ru3(CO)12] afford moderate yields of the polymers [-SiRR′-Ru(CO)4-Ru(CO)4-SiRR′-C6H4-]n which exhibit large solvent-dependent change of the UV-VIS spectra. The absorption maximum of the polymer is markedly red-shifted, compared with monomeric complex [PhMe2SiRu(CO)4Ru(CO)4SiMe2Ph].
High-Spin Oxyphenylbenzo-Annelated Dehydro[12]annulene
Authors: Pu Yong-Jin , Takahashi Masahiro , Tsuchida Eishun , Nishide Hiroyuki 
Published: May 2003

Abstract
A ground state quartet molecule, 2,8,14-trisoxyphenyltribenzotrisdehydro[12]annulene, was synthesized; the dehydroannulene acted as an effective ferromagnetic coupler for the pendant spins.
Conformational and Intramolecular Hydrogen-Bonding Properties of Substituted Dithia[3.3]metacyclophanes
Authors: Moriguchi Tetsuji , Sakata Kazunori , Tsuge Akihiko 
Published: May 2003

Abstract
Conformational properties and intramolecular hydrogen-bondings of dithia[3.3]metacyclophanes carrying one or two amino group on their internal positions were studied by 1H-NMR, IR spectra and X-ray structural analyses. It was found out that intramolecular hydrogen-bonding network between amino protons and bridge sulfur atoms is formed and it is closely related to the conformations of cyclophanes.
One-way cis to trans Photoisomerization in Styrylnaphthalene Derivative: Role of Substituents and Solvent
Authors: Bushan K Mani , Ayodele E Temidayo , Gopal V Raj , Soujanya T , Rao V Jayathirtha 
Published: May 2003

Abstract
One-way cis to trans photoisomerization is achieved in styrylnaphthalene derivative (3) by suppressing the trans to cis isomerization with the use of suitable substituents and solvents.
Photoreactions of N-Methyl-1,8-naphthalimide with Methylbenzenes: [3+3]-Additions and Water-Incorporated Additions
Authors: Kubo Yasuo , Fuseya Nobuhiro , Nakajima Satoshi 
Published: May 2003

Abstract
Novel [3+3]-additions and water (methanol)-incorporated additions were observed in the photoreactions of N-methyl-1,8-naphthalimide with methylbenzenes, such as xylenes, mesitylene, and durene, in acetonitrile. A mechanism for the reactions is proposed on the basis of the fluorescence quenching examinations, calculations of ΔG associated with the electron transfer, and deuteration studies.
Regiocontrol of Diels-Alder Reaction of Conjugate 1-Trienol Ether in Chiral Tropilidene with TCNE
Authors: Sugimura Takashi , Nagano Shinya , Kohno Harumi , Fujita Morifumi , Tai Akira 
Published: May 2003

Abstract
The Diels-Alder reaction of tetracyanoethylene (TCNE) with a 1-trienol unit in the tropilidenes at the 1,4-position was a quick and reversible process, whereas the 3,6-addition only proceeded in polar solvent and was irreversible.
The Most Effective Packing of Layers: Synthesis and Structure of [Ni(4,4′-bipyridine)2(NCS)2]n
Authors: Zhang Yugen , Jianmin Li , Wei Deng , Nishiura Masayoshi , Imamoto Tsuneo 
Published: May 2003

Abstract
The complex [Ni(4,4′-bipyridine)2(NCS)2]n, in which nickel atoms are linked by two different Ni-4,4′-bpy-Ni assemblies to form two-dimensional distorted square net structure and the most effective packing of layers, has been isolated and structurally characterized.
A New Approach to Organic/Inorganic Composites. Thin Film Coating of CaCO3 on a Chitin Fiber in the Presence of Acid-Rich Macromolecules
Authors: Kato Takashi , Amamiya Takahiro 
Published: May 2003

Abstract
Thin film coating of CaCO3 crystals on a chitin fiber from CaCO3 solution in the presence of an acid-rich macromolecule leads to the fabrication of a novel type of organic/inorganic composites. Molecular interactions between functional groups of these organic matrices play a key role for this control of inorganic crystallization.
Formation of Aluminum Nitride Using Lithium Nitride as a Source of N3− in the Molten Aluminum Chloride
Authors: Sonoyama Noriyuki , Yasaki Yoichi , Sakata Tadayoshi 
Published: May 2003

Abstract
Synthesis of aluminum nitride, known as wide gap semiconductor, was attempted by the molten salt method using lithium nitride as the source of N3− ion and aluminum chloride as the source of aluminum ion and the medium of lithium nitride at 250 °C. Production of aluminum nitride was recognized from the spectra of XRD and XPS. Production of aluminum nitride suggests the simple reaction mechanism that the N3− ion ionize from lithium nitride in the molten aluminum chloride with Al3+ ion.
Alkylation of Benzene with Ethane over Platinum-loaded H-ZSM5 Catalyst
Authors: Kato Shinjiro , Nakagawa Kiyoharu , Ikenaga Na-oki , Suzuki Toshimitsu 
Published: May 2003

Abstract
Ethylbenzene was prepared from benzene and ethane, using platinum-loaded H-ZSM5 catalyst at 500°C, giving the ethylbenzene and styrene space time yields of 14.2 and 0.8 mmol h−1·g−1 of catalyst, respectively (benzene-based yields 6.9 and 0.4%).
Magnetic Enhancement of Electrochemical Current over Interdigitated Dot Electrodes
Authors: Rashkov Rashko S , Aogaki Ryoichi , Nakabayashi Seiichiro 
Published: May 2003

Abstract
Current over interdigitated dot electrodes increased under magnetic field. Mach-Zehnder laser interferometer revealed that the magnetic field tilted the fluid motion over the dot electrodes. This induced lateral movement enhanced the mass transport including redox cycling among the electrodes and consequently, the current.
A Novel Three-Dimensional Framework: Self-Assembly of AgNO3 and Pyrimidine
Authors: Cai Hu , Hu Huai-Ming , Chen Wan-Zhi , Zhu Hao-Guo , You Xiao-Zeng 
Published: May 2003

Abstract
The uncharged complex {Ag(pyrimidine)0.5NO3}∞ is prepared and characterized by X-ray diffraction studies which reveal a novel non-centrosymmetric three-dimensional (3-D) framework based both on the metal ions bound to ligands and anion bonding mode.
Facile Preparation of Robust Organic Gels by Cross-link of a Sugar-integrated Gelator by Toluene-2,4-diisocyanate
Authors: Inoue Kazuhiko , Ono Yoshiyuki , Kanekiyo Yasumasa , Kiyonaka Shigeki , Hamachi Itaru , Shinkai Seiji 
Published: May 2003

Abstract
Gelator 1 which has two aliphatic chains, three amide groups, and one glucosamine unit showed an excellent gelation ability for many organic solvents. The in situ cross-link of these organic gels by toluene-2,4-diisocyanate resulted in new robust gels with high Tgel values, retaining their gel fiber super-structure.
Acceleration of Photoinduced Electron Transfer in Porphyrin-Linked C70
Authors: Tamaki Koichi , Imahori Hiroshi , Nishimura Yoshinobu , Yamazaki Iwao , Shimomura Akihisa , Okada Tadashi , Sakata Yoshiteru 
Published: May 2003

Abstract
Porphyrin-linked C70 and porphyrin-linked C60 dyads have been designed and synthesized to evaluate the intrinsic properties of C70 in electron transfer. The photoinduced charge separation in the former is accelerated by a factor of about two compared with that in the latter. The result shows that C70 can be added to potential building blocks in artificial photosynthesis.
Evidence for the Importance of a Cationic Charge in the Formation of Hollow Fiber Silica from an Organic Gel System
Authors: Ono Yoshiyuki , Kanekiyo Yasumasa , Inoue Kazuhiko , Hojo Junichi , Shinkai Seiji 
Published: May 2003

Abstract
To obtain an insight into the mechanism for the construction of novel hollow fiber silica (“macaroni silica”), sol-gel polymerization of tetraethoxysilane was carried out in the organic gels prepared in the presence of a benzo-18-crown-6-containing cholesterol gelator. Hollow fiber silica was obtained only in the presence of the high concentration of KClO4. The findings support the view that the cationic charge plays a role indispensable to the construction of the tubular structure.
Formation of Trimethylpentanes from Isobutane and 1-Butene Catalyzed by Sulfated Metal Oxides
Authors: Satoh Kunihiko , Matsuhashi Hiromi , Arata Kazushi 
Published: May 2003

Abstract
The gas-phase alkylation of 1-butene with isobutane was carried out over superacids of sulfated metal oxides, SO4/Fe2O3, SO4/Al2O3, SO4/TiO2, SO4/SnO2, and SO4/ZrO2, at 0°C; SO4/SnO2 gave the highest yield of trimethylpentane (TMP). It was proved from relationship between the catalyst acidities and the yields of C8 paraffins that the first intermediate species was a t-butyl cation formed on the superacidic Lewis site by abstraction of H− followed by the alkylation with butenes to form TMP.
Photochemical Doping of TCNQ by Photoinduced Electron Transfer and C-C Cleavage of Radical Cation
Authors: Yokoi Hajime , Ishiguro Katsuya , Sawaki Yasuhiko 
Published: May 2003

Abstract
The irradiation with UV light (λ&gt;350 nm) of mixed powder of tetracyanoqunodimethane (TCNQ) and donor (D–D) resulted in the formation of TCNQ−• indicating that TCNQ could be doped by irreversible photoinduced electron transfer and C–C cleavage of D–D+•.
Enzymatic Preparation of Malate-Based Polycarboxylates Having Higher Molecular Weights by Copolymerization with Lactone
Authors: Matsumura Shuichi , Beppu Hideki , Toshima Kazunobu 
Published: May 2003

Abstract
A strategy for increasing the molecular weight of malate-based polycarboxylates by the enzymatic polymerization of benzyl β-malolactonate (BML) with organic additives was studied. The lipase-catalyzed ring-opening polymerization of BML was significantly promoted by the addition of a small amount of β-propiolactone (PL) to yield polycarboxylates having an Mw of 32000 without a significant decrease in the inherent carboxy content.
Propane Oxidative Dehydrogenation over Nickel Supported on Sulfated Zirconia
Authors: Wang Shaobin , Murata Kazuhisa , Hayakawa Takashi , Hamakawa Satoshi , Suzuki Kunio 
Published: May 2003

Abstract
Excellent performance for the oxidative dehydrogenation of propane is achieved over lithium promoted nickel supported on sulfated zirconia, giving propylene selectivity of 50% at propane conversion of 20%.