bluuebunny/crossref_metadata_2025_split huggingface dataset:
Structure of resorcinol, phenol, and furan resins by MALDI‐TOF mass spectrometry and 13C NMR
Authors: Pizzi A. , Pasch H. , Simon C. , Rode K. 
Published: April 2004

AbstractThe structure of traditional, linear phenol–resorcinol–formaldehyde (PRF) resins, urea‐branched PRF resins, and phenol–resorcinol–furfural (PRFuran) resins has been investigated in depth by both matrix‐assisted laser desorption/ionization time of flight (MALDI‐TOF) mass spectroscopy and 13C NMR. The structure of a variety of oligomers has been obtained, and the structures present in each of the three types of resins related to the very different percentages of resorcinol needed for their equal performance as adhesives. The oligomers type and species distribution appeared very different for each case. PRF resins performance is improved by maximizing either the proportion of resorcinol‐containing oligomers or methylol‐groups containing oligomers, even without any resorcinol, or both. It is equally obtained by the minimization of the relative proportion of the low reactivity Phenol (CH2 Phenol) species in which resorcinol is not present, this being the most important parameter. This can be obtained by more effective use of the resorcinol by just modifying the resin manufacturing procedure. This parameter instead does not appear to be determinant in PRFuran resins. In these, it is the higher molecular weight of furfural in relation to formaldehyde that engenders for the same manufacturing procedure a correspondingly lower proportion of resorcinol in the resin. © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 92: 2665–2674, 2004
The virial theorem for subsystems: application to a globular cluster within a galaxy
Authors: Caimmi R. 
Published: April 2004

AbstractA self‐similar evolution of a globular cluster within a galaxy, which implies a one‐component formulation of the virial theorem (Mouri & Taniguchi 2003), is extended to a two‐component formulation (Caimmi & Secco 2003). To this aim, the general case of an embedded sphere within an embedding sphere, both represented as truncated, singular isothermal spheres, is applied to the situation of interest. It is shown that, in the case under consideration, a two‐component formulation of the virial theorem reproduces the analytical results of a one‐component formulation. The process of energy change due to mass loss through the surface is analysed in detail, in connection with both a one‐component and a two‐component formulation of the virial theorem. (© 2004 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Photometric solution of the eclipsing binary system EF Boötis
Authors: Özdemir S. , Demircan O. , Çiçek C. , Erdem A. 
Published: April 2004

AbstractThe EF Boo eclipsing binary system is studied in the context of optical light curves and radial velocity curves published in the literature. The best‐solution leads to an over‐contact configuration of W–subclass of WUMa systems with a fill‐out factor of 28%. Absolute parameters based on simultaneous solution of light and radial velocity curves are presented. (© 2004 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Bioequivalence evaluation of two brands of ketoconazole tablets (Onofin‐K® and Nizoral®) in a healthy female Mexican population
Authors: Marcelín‐Jiménez G. , Hernández José , Ángeles Alionka P. , Contreras L. , Hinojosa M. , Rivera L. , Martínez‐Rossier L. , Amancio O. , Fernández A. 
Published: April 2004

AbstractA randomized, crossover study was conducted in 24 healthy female volunteers to compare the bioavailability of two brands of ketoconazole (200 mg) tablets; Onofin‐K® (Farmacéuticos Rayere S.A., México) as the test and NIZORAL® (Janssen‐Cilag, México) as the reference products. The study was performed at the Clinical Pharmacology Research Center of the Hospital General de México in Mexico City. Two tablets (400 mg) were administered as a single dose with 250 ml of water after a 12 h overnight fast on two treatment days separated by a 1 week washout period. After dosing, serial blood samples were collected for a period of 12 h. Plasma harvested was analysed for ketoconazole by a modified and validated HPLC method with UV detection in the range 400–14000 ng/ml, using 200 µl of plasma in a full‐run time of 2.5 min. The pharmacokinetic parameters AUC0−t, AUC0−α, Cmax, Tmax and t1/2 were determined from plasma concentrations of both formulations and the results discussed. AUC0−t, AUC0−α and Cmax were tested for bioequivalence after log transformation of data, and no significant differences were found either in 90% classic confidence interval or in the Anderson and Hauck test (p<0.05). Based on statistical analysis, it is concluded that Onofin‐K® is bioequivalent to Nizoral®. Copyright © 2004 John Wiley & Sons, Ltd.
Pregnancy outcomes following systemic prenatal acyclovir exposure: Conclusions from the international acyclovir pregnancy registry, 1984–1999
Authors: Stone Katherine M. , Reiff‐Eldridge Robbin , White Alice D. , Cordero José F. , Brown Zane , Alexander E. Russell , Andrews Elizabeth B. 
Published: April 2004

AbstractBACKGROUNDOral acyclovir is commonly used for genital herpes and other herpesvirus infections. Data on potential fetal risk are extremely limited. From 1984 to 1998, the Acyclovir in Pregnancy Registry monitored birth outcomes of women exposed to oral or intravenous acyclovir during pregnancy. This report describes the final results.METHODSThe registry was publicized to health care providers most likely to diagnose pregnancy; providers called the registry telephone number, then mailed in a brief questionnaire. Pregnancy outcomes were categorized either as outcomes with birth defects or outcomes without birth defects, subcategorized as live births, spontaneous pregnancy losses (including stillbirths), and induced abortions. Birth defects were defined using a modification of the CDC definition for birth defects surveillance systems. Observed rates were compared to the rate (3.2%) of birth defects expected in the general population.RESULTSBetween June 1, 1984 and June 30, 1998, 1695 pregnancies exposed to oral or IV acyclovir were registered; 461 (27%) were lost to follow‐up. A total of 1234 pregnancies in 24 countries were followed, with a total of 1246 outcomes. Among 1246 pregnancy outcomes, 756 involved acyclovir exposure in the first trimester, 197 in the second trimester, and 291 in the third trimester. Among live births with first trimester acyclovir exposure, risk of birth defects was 19 of 596 (3.2%; 95% CI, 2.0–5.0%). No unusual defects or pattern of defects were apparent.CONCLUSIONSThe observed rates and types of birth defects for pregnancies exposed to acyclovir did not differ significantly from those in the general population. Birth Defects Research (Part A), 2004. Published 2004 Wiley‐Liss, Inc.
Structural characterization of VGVAPG, an elastin‐derived peptide
Authors: Floquet Nicolas , Héry‐Huynh Stéphanie , Dauchez Manuel , Derreumaux Philippe , Tamburro Antonio M. , Alix Alain J. P. 
Published: April 2004

AbstractElastic fibers are an important component of the extracellular matrix, providing elasticity and resilience to tissues that require the ability to deform repetitively and reversibly. Among the elastin‐derived peptides, the Val–Gly–Val–Ala–Pro–Gly (VGVAPG) hexapeptide is known for its chemotactic activity and metalloproteinases upregulation properties. As other elastin‐derived peptides, having homologous similar sequences, do not exhibit any biological activity, the following question arises: Does the peptide–receptor interaction need a specific active conformation? Previous experimental studies including NMR and CD spectroscopies did not clearly identify the conformations adopted by the VGVAPG peptide in solution. However, structural predictions made on VGVAPG and related XGXXPG peptides suggested a folded β‐turn conformation. So we undertook a theoretical and experimental study of the VGVAPG peptide. The work presented here, which gives an overall structural description of VGVAPG behavior in water, also provides an additional insight into its structure–activity relationship. Both theoretical and experimental results suggest the existence of an ensemble of rather extended and folded conformations in solution. All the folded structures obtained exhibit a type VIII β‐turn spanning the GVAP sequence. In the lack of any structural information concerning the elastin receptor, these results suggest that such a conformation could be relevant for the peptide–receptor interaction and thus for biological activity. © 2004 Wiley Periodicals, Inc. Biopolymers (Pept Sci), 2004
Structural characterization of glutamine synthetase from Azospirillum brasilense
Authors: Kamnev Alexander A. , Antonyuk Lyudmila P. , Smirnova Victoria E. , Kulikov Leonid A. , Perfiliev Yury D. , Kudelina Irina A. , Kuzmann Ernő , Vértes Attila 
Published: April 2004

AbstractCD spectroscopic study of the secondary structure of partly adenylylated glutamine synthetase (GS) of the bacterium Azospirillum brasilense showed both the native and cation‐free (EDTA‐treated) enzyme to be highly structured (58 and 49% as α‐helices, 10 and 20% as β‐structure, respectively). Mg2+, Mn2+, or Co2+, when added to the native GS, had little effect on its CD spectrum, whereas their effects on the cation‐free GS were more pronounced. Emission (57Co) Mössbauer spectroscopic (EMS) study of 57Co2+‐doped cation‐free GS in frozen solution and in the dried state gave similar spectra and Mössbauer parameters for the corresponding spectral components, reflecting the ability of the Co2+–enzyme complex to retain its properties upon drying. The EMS data show that (a) A. brasilense GS has 2 cation‐binding sites per active center and (b) one site has a higher affinity to Co2+ than the other, in line with the data on other bacterial GSs. © 2004 Wiley Periodicals, Inc. Biopolymers, 2004
Production of nickel bio‐ore from hyperaccumulator plant biomass: Applications in phytomining
Authors: Boominathan Rengasamy , Saha‐Chaudhury N. M. , Sahajwalla Veena , Doran Pauline M. 
Published: April 2004

AbstractAn important step in phytomining operations is the recovery of metal from harvested plant material. In this work, a laboratory‐scale horizontal tube furnace was used to generate Ni‐enriched bio‐ore from the dried biomass of Ni hyperaccumulator plants. Prior to furnace treatment, hairy roots of Alyssum bertolonii were exposed to Ni in liquid medium to give biomass Ni concentrations of 1.9% to 7.7% dry weight; whole plants of Berkheya coddii were grown in Ni‐containing soil to produce above‐ground Ni levels of up to 0.49% dry weight. The concentration of Ca in the Ni‐treated B. coddii biomass was about 15 times greater than in A. bertolonii. After furnace treatment at 1200°C under air, Ni‐bearing residues with crystalline morphology and containing up to 82% Ni were generated from A. bertolonii. The net weight loss in the furnace and the degree of concentration of Ni were significantly reduced when the furnace was purged with nitrogen, reflecting the importance of oxidative processes in Ni enrichment. Ni in the B. coddii biomass was concentrated by a factor of about 17 to yield a residue containing 8.6% Ni; this bio‐ore Ni content is substantially higher than the 1% to 2% Ni typically found in mined ore. However, the B. coddii samples after furnace treatment also contained about 34% Ca, mainly in the form of hydroxyapatite Ca5(PO4)3OH. Such high Ca levels may present significant challenges for further metallurgical processing. This work demonstrates the feasibility of furnace treatment for generating Ni‐rich bio‐ore from hyperaccumulator plants. The results also suggest that minimizing the uptake of Ca and/or reducing the Ca content of the biomass prior to furnace treatment would be a worthwhile strategy for improving the quality of Ni bio‐ore produced in phytomining operations. © 2004 Wiley Periodicals, Inc.
Isolation of a fluffy mutant of Aspergillus niger from chemostat culture and its potential use as a morphologically stable host for protein production
Authors: van de Vondervoort Peter J. I. , Poulsen Bjarne R. , Ruijter George J. G. , Schuleit Tina , Visser Jaap , Iversen Jens J. L. 
Published: April 2004

AbstractChemostat cultivation of Aspergillus niger and other filamentous fungi is often hindered by the spontaneous appearance of morphologic mutants. Using the Variomixing bioreactor and applying different chemostat conditions we tried to optimize morphologic stability in both ammonium‐ and glucose‐limited cultures. In most cultivations mutants with fluffy (aconidial) morphology became dominant. From an ammonium‐limited culture, a fluffy mutant was isolated and genetically characterized using the parasexual cycle. The mutant contained a single morphological mutation, causing an increased colony radial growth rate. The fluffy mutant was subjected to transformation and finally conidiospores from a forced heterokaryon were shown to be a proper inoculum for fluffy strain cultivation. © 2004 Wiley Periodicals, Inc.
Modeling the effects of assimilable nitrogen and temperature on fermentation kinetics in enological conditions
Authors: Malherbe S. , Fromion V. , Hilgert N. , Sablayrolles J.‐M. 
Published: April 2004

AbstractWe propose a dynamic model of alcoholic fermentation in wine‐making conditions. In this model, the speed at which CO2 is released is related to the effects of the main factors involved in fermentation in wine‐making conditions: temperature (which can vary within a predefined range) and nitrogen additions (which must not exceed the maximal authorized level). The resulting model consists of ordinary differential equations including numerous parameters that need to be identified and important interactions between explicative variables. These parameters were identified by uncoupling the effects of variables during specific experiments. The results were validated on another series of experiments in different conditions. © 2004 Wiley Periodicals, Inc.
Enantioselective Total Syntheses of the Ipecacuanha Alkaloid Emetine, the Alangium Alkaloid Tubulosine and a Novel Benzoquinolizidine Alkaloid by Using a Domino Process
Authors: Tietze Lutz F. , Rackelmann Nils , Müller I. 
Published: April 2004

AbstractThe first enantioselective syntheses of the Ipecacuanha alkaloid emetine (1) and the Alangium alkaloid tubulosine (2) is described employing a domino Knoevenagel/hetero‐Diels–Alder reaction and an enantioselective catalytic transfer hydrogenation of imines as key steps. Thus, hydrogenation of the imine 15 with the catalyst (R,R)‐16 gives the tetrahydroisoquinoline 14 with 95 % ee which was transformed into the aldehyde (1S)‐7. The three‐component domino reaction of (1S)‐7 with 6 and 8 led to 19, which in a second domino process was treated with K2CO3 in methanol followed by a hydrogenation to give the benzoquinolizidine 4 together with the diastereomers 22 and 23 in a overall yield of 66 %. Further transformation of 4 with the amines 3 and 5 yielded enantiopure emetine (1) and tubulosine (2), respectively. In addition, starting from 19 the novel benzoquinolizidine alkaloid 34 was synthesised; this compound resembles the vallesiachotamine alkaloid dihydroantirhin 31, which has not been isolated so far but probably must also exist in nature.
New Double Salts with Boron‐Centered Zirconium Clusters: Syntheses and Structures of Cs[ZrCl5]×Cs2[(Zr6B)X15] (X: Cl or Cl + I), and Anion Distribution in the Mixed Halide Phase.
Authors: Rohm Henning W. , Koeckerling Martin 
Published: April 2004

AbstractFor Abstract see ChemInform Abstract in Full Text.
Lithium and Sodium Yttrium Orthosilicate Oxyapatite, LiY9(SiO4)6O2 and NaY9(SiO4)6O2, at Both 100 K and Near Room Temperature.
Authors: Redhammer Guenther R. , Roth G. 
Published: April 2004

AbstractFor Abstract see ChemInform Abstract in Full Text.
Asymmetric Addition of Aryl Boron Reagents to Enones with Rhodium Dicyclophane Imidazolium Carbene Catalysis.
Authors: Ma Yudao , Song Chun , Ma Changqing , Sun Zhijun , Chai Qiang , Andrus Merritt B. 
Published: April 2004

AbstractFor Abstract see ChemInform Abstract in Full Text.
Zn(ClO4)2×6H2O as a Powerful Catalyst for a Practical Acylation of Alcohols with Acid Anhydrides.
Authors: Bartolli Giuseppe , Bosco Marcella , Dalpozzo Renato , Marcantoni Enrico , Massaccesi Massimo , Sambri Letizia 
Published: April 2004

AbstractFor Abstract see ChemInform Abstract in Full Text.
Studies on K2CO3‐Catalyzed 1,4‐Addition of 1,2‐Allenic Ketones with Diethyl Malonate: Controlled Selective Synthesis of β,γ‐Unsaturated Enones and α‐Pyrones.
Authors: Ma Shengming , Yu Shichao , Yin Shaohu 
Published: April 2004

AbstractFor Abstract see ChemInform Abstract in Full Text.
A Convenient Stereoselective Synthesis of β‐Lactams from β‐Hydroxy‐α‐thioalkylesters Prepared from Michael/Aldol Tandem Reaction or Stereoselective Addition of Thiols to the Baylis—Hillman Adducts.
Authors: Kamimura Akio , Morita Rie , Matsuura Kenji , Mitsudera Hiromasa , Shirai Masashi 
Published: April 2004

AbstractFor Abstract see ChemInform Abstract in Full Text.
Determining the Scope of the Organolanthanoid‐Catalyzed, Sequential Intramolecular Amination/Cyclization Reaction: Formation of Substituted Quinolizidines, Indolizidines, and Pyrrolizidines.
Authors: Molander Gary A. , Pack Shawn K. 
Published: April 2004

AbstractFor Abstract see ChemInform Abstract in Full Text.
Polysubstituted Pyrazoles. Part 5. Synthesis of New 1‐(4‐Chlorophenyl)‐4‐hydroxy‐1H‐pyrazole‐3‐carboxylic Acid Hydrazide Analogues and Some Derived Ring Systems. A Novel Class of Potential Antitumor and anti‐HCV Agents.
Authors: Rostom Sherif A. F. , Shalaby Manal A. , El‐Demellawy Maha A. 
Published: April 2004

AbstractFor Abstract see ChemInform Abstract in Full Text.
One‐Pot Synthesis of Substituted Naphthyridines and 2H‐Pyrano[3,2‐g]quinolin‐2‐ones in Water.
Authors: Rosas Noe , Sharma Pankaj , Cabrera Armando , Penieres Guillermo , Garcia Jose L. , Maldonado Luis A. 
Published: April 2004

AbstractFor Abstract see ChemInform Abstract in Full Text.
A New Tetracyclic Ring System of Biological Interest: Indolo[3,2‐e][1,2,3]triazolo[1,5‐a]pyrimidines Through Domino Reactions of 2‐Azidoindole.
Authors: Lauria Antonino , Patella Chiara , Diana Patrizia , Barraja Paola , Montalbano Alessandra , Cirrincione Girolamo , Dattolo Gaetano , Almerico Anna Maria 
Published: April 2004

AbstractFor Abstract see ChemInform Abstract in Full Text.
Synthesis and in vitro Antiprotozoal Activity of a Series of Benzotropolone Derivatives Incorporating Endocyclic Hydrazines.
Authors: Ren Hongyu , Grady Shannon , Banghart Matthew , Moulthrop Jason S. , Kendrick Howard , Yardley Vanessa , Croft Simon L. , Moyna Guillermo 
Published: April 2004

AbstractFor Abstract see ChemInform Abstract in Full Text.
Synthesis of 3′‐Deoxy‐3′‐[4‐(pyrimidin‐1‐yl)methyl‐1,2,3‐triazol‐1‐yl]thymidine via 1,3‐Dipolar Cycloaddition.
Authors: Tourirte M. , Oulih T. , Lazrek H. B. , Barascut J. L. , Imbach J. L. , Almasoudi N. A. 
Published: April 2004

AbstractFor Abstract see ChemInform Abstract in Full Text.
Amphidinolide Y, a Novel 17‐Membered Macrolide from Dinoflagellate Amphidinium sp.: Plausible Biogenetic Precursor of Amphidinolide X.
Authors: Tsuda Masashi , Izui Naoko , Shimbo Kazutaka , Sato Masaaki , Fukushi Eri , Kawabata Jun , Kobayashi Jun'ichi 
Published: April 2004

AbstractFor Abstract see ChemInform Abstract in Full Text.
Proposal of new RSVP which considers maximum waiting time for bandwidth reservation
Authors: Ikebe Takashi , Honda Hiroki , Yuba Toshitsugu 
Published: April 2004

AbstractA conventional IP network is a connectionless, best effort network, but has difficulty guaranteeing the Quality of Service (QoS). To guarantee end‐to‐end QoS, the Internet Engineering Task Force (IETF) has proposed bandwidth reservation protocols such as the Resource ReSerVation Protocol (RSVP), but a protocol that guarantees all bandwidth reservation requests has not been realized. To address this, with the objective of implementing bandwidth reservation capable of reliably accepting the bandwidth reservation requests regardless of the size of the requested bandwidth, the authors proposed Waiting Bandwidth Reservation Communication, which is an extension of RSVP. By using this method, we verified that excellent results compared to conventional RSVP are obtained when all bandwidth reservation communications pass over a special path and the bandwidth reservation requests exceed the bandwidth available for reservation along that path. On the other hand, in a wide‐area network such as the Internet, the problems are that all of the bandwidth reservation communications are not along special paths and unnecessary waits are generated when waiting for bandwidth reservations. With the objective of solving these problems, in this paper, we propose RSVP that considers the waiting time until the start of bandwidth reservation and demonstrate through simulations how the proposed method solves these problems. © 2004 Wiley Periodicals, Inc. Electron Comm Jpn Pt 1, 87(8): 71–81, 2004; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/ecja.10103
A shared buffer memory switch with multicast function using generalized two‐level priority control
Authors: Tada Mitsukazu , Inoue Takeshi , Komatsu Masaharu 
Published: April 2004

AbstractIn the future, various multicast applications are anticipated for ATM networks, and many studies have examined ATM switches having the multicast function. In a shared buffer switch, the cell loss performance is clearly improved by unicast priority control that gives send priority to the unicast cell in an address copy switch. However, if the multicast traffic increases, a reduction in the priority control effect becomes a problem. To solve this unicast priority control problem, in this paper, we propose two generalized two‐level priority control schemes (deterministic‐threshold scheme and adaptive‐threshold scheme) that give priority to cells having the number of copies below some threshold. The deterministic‐threshold scheme sets the optimum threshold when the traffic state is known, and clearly reduces the cell loss probability even when the ratio of multicast cells in the input traffic is high. The problem becomes what to set the threshold to because the optimum threshold changes depending on the traffic state in this scheme. The adaptive‐threshold scheme always maintains the priority control effect by automatically changing the threshold in response to traffic variations based on the result obtained from the deterministic‐threshold scheme. We use simulations to compare the adaptive scheme to conventional schemes and demonstrate the effectiveness of the adaptive‐threshold scheme. © 2004 Wiley Periodicals, Inc. Electron Comm Jpn Pt 1, 87(8): 63–70, 2004; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/ecja.10111
A new quantization method for SAR signals
Authors: Shirakawa Tomoaki , Shimono Tetsuo , Kitajima Hideo 
Published: April 2004

AbstractWe propose a new quantization method for received synthetic aperture radar (SAR) signals and a quantizer design technique. This method divides the received signal into bandlimited signals by using orthogonal wavelet transforms and quantizes each bandlimited signal by a different quantizer. Employing this method, not only is there a reduction in the computational load for image reconstruction by the SAR fast approximate reconstruction proposed previously by the authors, but the accuracy of the reconstructed image is substantially improved when there are few quantization bits of the received signal, particularly in image reconstruction by the correlation method. In this paper, we design a quantizer for bandlimited signals and demonstrate the effectiveness of the proposed method by computer simulations of image reconstruction. © 2004 Wiley Periodicals, Inc. Electron Comm Jpn Pt 1, 87(9): 54–63, 2004; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/ecja.10182