bluuebunny/crossref_metadata_2025_split huggingface dataset:
Density‐dependent prophylaxis and condition‐dependent immune function in Lepidopteran larvae: a multivariate approach
Authors: Cotter S. C. , Hails R. S. , Cory J. S. , Wilson K. 
Published: March 2004

Summary

The risk of parasitism and infectious disease is expected to increase with population density as a consequence of positive density‐dependent transmission rates. Therefore, species that encounter large fluctuations in population density are predicted to exhibit plasticity in their immune system, such that investment in costly immune defences is adjusted to match the probability of exposure to parasites and pathogens (i.e. density‐dependent prophylaxis).
Despite growing evidence that insects in high‐density populations show the predicted increase in resistance to certain pathogens, few studies have examined the underlying alteration in immune function. As many of these species show increased cuticular melanism at high densities, the aim of this study was to use a multivariate approach to quantify relative variation in the allocation of resources to immunity associated with both rearing density (solitary vs. crowded) and cuticular colour (pale vs. dark) in a phase‐polyphenic Lepidopteran species (Spodoptera littoralis Boisduval).
Relative to pale individuals, dark larvae (the high‐density phenotype) exhibited higher haemolymph and cuticular phenoloxidase (PO) activity and a stronger melanotic encapsulation response to an artificial parasite inserted into the haemocoel. However, they also exhibited lower antibacterial (lysozyme‐like) activity than pale larvae. Larval density per se had little effect on most of the immune parameters measured, though capsule melanization and antibacterial activity were significantly higher in solitary‐reared than crowded larvae.
Correcting for variation in larval body condition, as estimated by weight and haemolymph protein levels, had little effect on these results, suggesting that variation in immune function across treatment groups cannot be explained by condition‐dependence. These results are examined in relation to pathogen resistance, and the possibility of a trade‐off within the immune system is discussed.
Prevalence of apical periodontitis and frequency of root‐filled teeth in an adult Spanish population
Authors: Jiménez‐Pinzón A. , Segura‐Egea J. J. , Poyato‐Ferrera M. , Velasco‐Ortega E. , Ríos‐Santos J. V. 
Published: March 2004

AbstractAim  To estimate the prevalence of teeth with apical periodontitis (AP) and root‐filled teeth in an adult Spanish population.Methodology  A total of 180 subjects, aged 37.1 ± 15.7 years, presenting as new patients to the Faculty of Dentistry, Seville, Spain, were examined. All participants underwent a full‐mouth radiographic survey (14 periapical radiographs). The frequency of root canal treatment and the periapical status of all teeth, using the periapical index (PAI) score, were assessed. An intraobserver agreement test on PAI scores produced a Cohen's kappa of 0.77 (substantial agreement). Results were analysed statistically using the Chi‐square test.Results  Apical periodontitis in one or several teeth was found in 110 subjects (61.1% prevalence), and 73 (40.6% prevalence) had at least one root‐filled tooth. Among subjects with root‐filled teeth, 48 (65.8%) had AP affecting at least one root‐filled tooth. A total of 4453 teeth were examined, of these 186 (4.2%) had AP. The total number of root‐filled teeth was 93 (2.1%), of which 60 (64.5%) had AP. Among non‐root filled teeth, only 2.9% had AP. The prevalence of AP in connection with molar teeth was higher (5.5%) than for premolar (4.5%) and anterior teeth (3.2%; P < 0.01). More premolar and molar teeth were root‐filled (2.8 and 2.7%, respectively) than anterior teeth (1.3%; P < 0.01). The prevalence of AP increased with age.Conclusions  The prevalence of AP in root‐filled and untreated teeth, and the frequency of root‐filled teeth were comparable to those reported in previous similar studies carried out in European countries. The prevalence of root‐filled teeth with AP was found to be higher compared to that demonstrated in other epidemiological studies.
Fraudulent management of digital endodontic images
Authors: Güneri P. , Akdeniz B. G. 
Published: March 2004

AbstractAim  To present examples of radiographic image reconstructions in endodontic treatment, to discuss the potential problems arising from the use of image processing software and to mention some current methods to prevent such counterfeit utilization of digital endodontic radiographs.Summary  Conventional Ultra‐Speed periapical films of root canal treatment were digitized with a flatbed scanner (Umax Powerlook II, Umax Technologies, Inc., Taiwan). Digital images were altered with photoshop 6.0 software (Adobe Corporation, San Jose, CA, USA). Carious lesions, periapical pathoses, fake root canals and artificial fillings were created, and inadequate treatment was corrected by application of various image manipulation functions of the software.Key learning points

Digital endodontic images can be altered with image processing software.
The use of digital radiographic data inevitably raises concerns about security, reliability and the potential for fraud.
Effects of calcium hydroxide on physical and sealing properties of canal sealers
Authors: Hosoya N. , Kurayama H. , Iino F. , Arai T. 
Published: March 2004

AbstractAim  To investigate whether Ca(OH)2 in four different agents alters the physical properties (Exp. I) and sealing ability (Exp. II) of root canal sealers.Experiment  (Exp. I) Calcipex® (Nippon Sika‐Yakuhin, Shimonoseki, Japan), Vitapex® (Neo‐Dental, Tokyo, Japan), Calkyl® (Showa Yakuhin, Tokyo, Japan), and Ca(OH)2 were used as Ca(OH)2 agents. Four sealers were tested for flow, working time, setting time, and film thickness: Canals® (Showa Yakuhin), Canals®‐N (Showa Yakuhin), Ketac™‐Endo (Espe, Seefeld, Germany), and Sealapex® (Kerr, Romulus, MI, USA). Each Ca(OH)2 agent was added to 10 vol.% of each sealer, and the mixture and controls without a Ca(OH)2 agent were tested according to ISO specifications. Measurements were compared using Student's t‐tests (P < 0.05). (Exp. II) After removing Ca(OH)2 agents applied to the root canals of 100 extracted human teeth, canals were filled with sealer. Controls were filled with each sealer without Ca(OH)2 agents. Sealing ability was evaluated using distance of dye penetration from the apices. Dye penetration data were compared using analysis of variance and post hoc Newman–Keuls test (P < 0.05).Results  Ca(OH)2 agents influenced the physical properties of the sealers. Flow and setting time met ISO requirements, but film thickness and working time did not. Apical sealing ability of all four sealers was influenced by Ca(OH)2 agents. The sealing ability of Sealapex® improved with all Ca(OH)2 agents. The physical and sealing abilities varied among the other sealers.Conclusions  Contact with Ca(OH)2 agents left on the canal wall caused considerable changes to the sealing ability of sealers.
The epidemiology of extrahepatic biliary atresia in New York State, 1983–98
Authors: Caton Alissa R. , Druschel Charlotte M. , McNutt Louise A. 
Published: March 2004

SummaryThe aetiology of biliary atresia, the leading cause of neonatal extrahepatic jaundice and the main indication for liver transplantation in children, is unknown. Recent research has focused on an infectious aetiology and the development of viral models in animals. The few published epidemiological studies report conflicting results for seasonal, geographical, and racial variations in incidence. In this study, New York State (NYS) Congenital Malformations Registry data from 1983 to 1998 were compared with resident live birth certificate data. County of residence, birth date, gestational age, birthweight, gender, maternal race and maternal age were extracted from the birth certificate data. Isolated and sequence cases were combined for analysis. Observed and expected numbers of cases were calculated by NYS region.Overall, 369 biliary atresia cases were reported in the 16‐year study period, a rate of 0.85 [95% CI 0.76, 0.93] per 10 000 live births. Of these, 249 isolated/sequence cases were ascertained, a rate of 0.57 [95% CI 0.50, 0.64] per 10 000 live births. The rate ratio of biliary atresia in New York City (NYC) compared with other NYS was 2.19 [95% CI 1.69, 2.84]. Seasonal patterns varied by region with spring births at highest risk in NYC and September to November births at highest risk in other NYS. The rate ratio in black vs. white mothers was 1.94 [95% CI 1.48, 2.54]. Birthweight and gestational age were associated with biliary atresia with preterm low‐birthweight infants at highest risk [RR 3.24, 95% CI 2.20, 4.76]. The association of isolated/sequence biliary atresia with season, preterm birth, and low birthweight in our study supports an infectious disease hypothesis.
Recruitment for a community‐based study of early pregnancy: the Right From The Start study
Authors: Promislow Joanne H. E. , Makarushka Christina M. , Gorman Jessica R. , Howards Penelope P. , Savitz David A. , Hartmann Katherine E. 
Published: March 2004

SummaryDespite the high incidence of spontaneous abortion, little is known about its causes, in part because of the challenge of assembling a large cohort of women in early pregnancy for prospective study. We describe the effectiveness of recruitment strategies used in Right From The Start (RFTS), a prospective, community‐based study of spontaneous abortion. Between December 2000 and September 2002, 803 pregnant women enrolled in RFTS, 103 of whom were recruited while trying to conceive. The mean gestational age at enrolment was 52 days, with 25% of the cohort enrolling before 6 completed weeks’ gestation. Participants recruited directly from the community typically enrolled earlier in their pregnancies (mean of 44 days) and accounted for 24% of the total cohort and 83% of all participants who were recruited while trying to conceive. Posting brochures in drug stores and targeted mailings to new homeowners were the most effective community recruitment strategies. Recruitment at private and public prenatal care sites accounted for 57% and 19% of the participants respectively. Recruitment from public clinics required direct contact by RFTS staff and yielded women who enrolled at later gestational ages (mean of 58 days), but was valuable for inclusion of minorities and lower income women with less favourable health behaviours. Although intensive, diverse efforts were required, when recruitment efforts were maximised, we successfully recruited over 10% of the estimated number of pregnant women in the community.
The Arabidopsis FtsH metalloprotease gene family: interchangeability of subunits in chloroplast oligomeric complexes
Authors: Yu Fei , Park Sungsoon , Rodermel Steven R. 
Published: March 2004

SummaryThe Arabidopsis At filamentation temperature sensitive (FtsH) metalloprotease gene family comprises 12 members (AtFtsH1–AtFtsH12), including three pairs of closely related genes that are targeted to chloroplasts (AtFtsH2 and AtFtsH8; AtFtsH1 and AtFtsH5; and AtFtsH7 and AtFtsH9). Mutations in AtFtsH5 (var1) and AtFtsH2 (var2) give rise to variegated plants with green‐ and white‐sectored leaves. Cells in the green sectors contain morphologically normal chloroplasts, whereas cells in the white sectors are blocked in chloroplast biogenesis. A major question is how chloroplasts arise in cells that have a mutant genotype. We have found by two‐dimensional (2‐D) green gel and gel filtration analyses that AtFtsH2/VAR2 forms oligomeric complexes. Two bands in the 2‐D green gels that correspond to AtFtsH5/VAR1 + AtFtsH1 and AtFtsH2/VAR2 + AtFtsH8 have been identified, and these bands are coordinately reduced in amount in var1 and var2 thylakoids that lack AtFtsH5/VAR1 and AtFtsH2/VAR2, respectively. These reductions are not because of alterations in transcript abundance. Overexpression of AtFtsH8 in var2‐4 (a putative null allele) normalizes the variegation phenotype of the mutant and restores the two bands to their wild‐type levels. These results suggest that AtFtsH8 is interchangeable with AtFtsH2/VAR2 in AtFtsH‐containing oligomers, and that the two proteins have redundant functions. Consistent with this hypothesis, AtFtsH2 and AtFtsH8 have similar expression patterns, as monitored by promoter–β‐glucuronidase (GUS) fusion and RT‐PCR experiments. Based on our findings, we propose that AtFtsH1, AtFtsH2/VAR2, AtFtsH5/VAR1, and AtFtsH8 interact to form oligomeric structures, and that subunit stoichiometry is controlled post‐transcriptionally in var1 and var2, perhaps by turnover. A threshold model is presented to explain the pattern of variegation in var2 in which AtFtsH8 provides a compensating activity in the green sectors of the mutant.
Microarray analysis of chromatin‐immunoprecipitated DNA identifies specific regions of tobacco genes associated with acetylated histones
Authors: Chua Yii Leng , Mott Ellie , Brown Anthony P. C. , MacLean Daniel , Gray John C. 
Published: March 2004

SummaryThe acetylation states of histones present on the upstream, promoter, coding or intronic regions of 88 tobacco genes were examined with chromatin immunoprecipitation (ChIP) experiments using antibodies that recognised acetylated histone H4. The DNA sequences enriched in the immunoprecipitates were amplified by ligation‐mediated PCR, labelled with Cy‐dUTP and hybridised to DNA microarrays. In green tobacco shoots, histone H4 acetylation was localised to 300–600‐bp sequences in the promoters or coding regions of 31 genes, or occurred extensively over several kilobase‐pair regions containing the upstream, promoter and/or coding regions of 25 genes. Genes associated with high histone H4 acetylation levels at promoters were actively expressed, whereas genes depleted in acetylated histone H4 were non‐transcribed or expressed at very low levels, suggesting a correlation between histone H4 acetylation and gene activity. Trichostatin A (TA), an inhibitor of histone deacetylases (HDAs), did not alter histone H4 acetylation states globally but increased acetylation levels at specific tobacco sequences, suggesting that HDAs are targeted to particular nucleosomes. Genes that were upregulated by TA were associated with increased histone H4 acetylation at promoter or coding regions, indicating that acetylation of histones on coding regions may activate transcription. Increased histone H4 acetylation leading to elevated expression was observed on genes with diverse functions, suggesting that histone H4 acetylation is involved in regulation of many plant processes.
Synthesis and Luminescent Properties of 2-Phenyl-5-{4[2-(6-substituent-2H-benz[de]isoquinoline-1,3(2H)-dione-2-yl) polymethano-]amino-}phenyl-1,3,4-oxadiazole
Authors: Ni Weijuan , Su Jianhua , Chen Kongchang , Tian He 
Published: March 2004

Abstract
Several new derivatives of 1,8-naphthalimide, which are connected with 1,3,4-oxadiazole via a covalent bond, have been synthesized. We have investigated the electroluminescent (EL) device fabricated with these new compounds. In these compounds 1,3,4-oxadiazole moiety facilitates the electron injection from the electrode and transfers its excited energy to 1,8-naphthalimide which acts as an emitting center. Greenish yellow EL peaked at 532 nm with a maximum luminous efficiency of 0.43 lm/W was observed.
Stable and Active AlPO4 Catalyst for Decomposition of CCl2F2
Authors: Takita Yusaku , Li Gong-Liang , Matsuzaki Rie , Wakamatsu Hironori , Nishiguchi Hiroyasu , Moro-oka Yoshihiko , Ishihara Tatsumi 
Published: March 2004

Abstract
CCl2F2 was decomposed to CO2 at 350–450 °C in the presence of water vapor and O2 over AlPO4 calcined at 1000 °C. CCl2F2 conversion slightly decreased at initial 50 h and then took a steady value. AlPO4 was not fluorinated during 1000 h reaction at 400 °C.
Reactions of Molybdenum(V)porphyrins with Phenol Derivatives Involving Parallel Inner and Outer Sphere Electron Transfer
Authors: Kurihara Masato , Saito Ikuko , Morinaga Yoko , Matsuda Yoshihisa 
Published: March 2004

Abstract
Reactions of oxoethoxomolybdenum(V)porphyrins and substituted phenols were investigated by UV-vis absorption spectra. Ligand substitution or reduction of the metal center proceeded depending on the steric repulsion between the substituents of the phenols and the porphyrin skeletons. Proton transfer from the phenols to the axial ligand of the molybdenumporphyrin initiated the reactions. Parallel outer sphere and inner electron transfer proceeded parallel in the reduction of the molybdenum center.
A Novel Synthesis of Spirocyclopropenes from the Haloallene Derivatives with Alkanethiolate Ions
Authors: Toda Takashi , Kuwana Masahiro , Ohhashi Yoshitaka , Yoshida Masaaki 
Published: March 2004

Abstract
Reactions of 1-bromo-1-substituted-2-(9-fluorenylidene)ethenes with alkanethiolate ions gava spiro[1-alkylthiocyclopropene-3,9′-fluorenes]. The bromoallene derived from 2,3-diphenylindene also afforded the corresponding spirocyclopropene compound.
Theoretical Prediction of the 31P NMR Chemical Shift of the Hexa-Coordinate Phosphorus Intermediate for the Phosphoryl Ester Exchange and N→O Migration Reactions of Dimethyloxyphosphoryl-Threonine
Authors: Zhan Chang-Guo , Iwata Suehiro 
Published: March 2004

Abstract
Ab initio GIAO magnetic shielding calculations have been carried out on the hexa-coordinate phosphorus intermediate and the corresponding reactant and product for the N→O migration reaction of dimethyloxyphosphoryl-threonine. The calculated results lead us to predict that the 31P NMR chemical shift of the hexa-coordinate phosphorus intermediate is −138 ppm, while the 31P chemical shifts of the corresponding reactant and product are 4.9 ppm and −6.6 ppm, respectively.
A Simple and Efficient Synthesis of Di-, Tri-, and Tetraferrocenylarenes
Authors: Iyoda Masahiko , Kondo Terumasa , Okabe Toshitaka , Matsuyama Haruo , Sasaki Shigeru , Kuwatani Yoshiyuki 
Published: March 2004

Abstract
A series of di-, tri-, and tetraferrocenylarenes were synthesized by using the nickel- and palladium-catalyzed cross coupling reactions of ferrocenylzinc chloride with the corresponding di-, tri-, and tetrahalogenoarenes. Redox properties of these ferrocenylarenes were studied by cyclic voltammetry in order to examine the intramolecular interaction between the ferrocenyl substituents.
Electrochemical Syntheses and Electrochromic Properties of Chromium Cyanide Magnetic Thin Films
Authors: Sato Osamu , Gu Zhongze , Etoh Hiroyuki , Ichiyanagi Jun-ichi , Iyoda Tomokazu , Fujishima Akira , Hashimoto Kazuhito 
Published: March 2004

Abstract
Electrochemical preparation method and electromic properties of the mixed valence chromium cyanide thin film, which is one of the ferrimagnet with highest critical temparature (Tc) among molecule-based magnets, were described. The difference in the ability of the ligand substitution reaction between CrII and CrIII was utilized to synthesize the prussian blue analogs. The obtained magnetic material exhibited an excellent electrochromic properties. This indicates the compound has a potential for future display devices, as well as tunable molecule-based magnetic devices.
Catalytic Asymmetric Addition Reaction of Dialkylzinc to Nitrone Utilizing Tartaric Acid Ester as a Chiral Auxiliary
Authors: Ukaji Yutaka , Shimizu Yuuko , Kenmoku Yuuichi , Ahmed Alauddin , Inomata Katsuhiko 
Published: March 2004

Abstract
The catalytic asymmetric addition reaction of dialkylzinc to carbon-nitrogen double bond in 3,4-dihydroisoquinoline N-oxide derivatives was achieved by utilizing a catalytic amount of dicyclopentyl (R,R)-tartrate to afford the corresponding (S)-hydroxylamines in high optical yields up to 94% ee.
Three-dimensional Cage-like Polycyanopolycadmate Network Accommodating Werner Complexes; The Crystal Structure of [Cd(dien)2]·[Cd2(CN)3(dien)2]·[Cd8(CN)19]·3H2O (dien = (H2N(CH2)2)2NH, diethylenetriamine)
Authors: Kurihara Hiroyuki , Nishikiori Shin-ichi , Iwamoto Toschitake 
Published: March 2004

Abstract
An anionic three-dimensional network host [Cd8(CN)19]3− enclathrates a cationic mononuclear Cd complex guest [Cd(dien)2]2+, and a dinuclear Cd complex guest [Cd2(CN)3(dien)2]+, to form a novel inclusion compound [Cd(dien)2]·[Cd2(CN)3(dien)2]·[Cd8(CN)19]·3H2O (dien = (H2N(CH2)2)2NH, diethylenetriamine).
Electrocatalytic Reduction of Dioxygen in the Presence of N,N′-Dipentyl Viologen
Authors: Oh Mi-Kyung , Okajima Takeyoshi , Kitamura Fusao , Lee Chi-Woo , Tokuda Koichi , Ohsaka Takeo 
Published: March 2004

Abstract
An excellent electrocatalysis of N,N′-dipentyl viologen, which is based on not the dissolved species but the adsorbed one, has been observed for the electroreduction of O2 to H2O2 at glassy carbon electrode in neutral aqueous media. The rate constant for the catalytic reaction was estimated to be ca.106∼107 M−1s−1 based on cyclic and hydrodynamic voltammetry.
A Novel Dinuclear Iridium(III) Complex with a Bridging Disulfide Bond. Conversion of Coordinated Thiolato to Coordinated Bridging Disulfide by Acid Oxidation
Authors: Konno Takumi , Miyashita Yoshitaro , Okamoto Ken-ichi 
Published: March 2004

Abstract
Treatment of fac(S)-[Ir(aet)3] (aet = 2-aminoethanethiolate) with acid in water gave a novel dinuclear Ir(III) complex, [Ir2(aet)4(cysta)]2+ (cysta = cystamine), in which two octahedral Ir(III) units are linked by a coordinated disulfide bond.
Loop Formation of Au Nanopaticles Adsorbed on Langmuir Monolayers
Authors: Kawai Takeshi , Watanabe Tomoyuki 
Published: March 2004

Abstract
A hybrid monolayer of Au nanoparticles and dioctadecyl-dimethylammonium chloride (DODAC) was formed at the air–water interface. The Au nanoparticles were found to form loop structures. The loops were 0.1–1 μm in size with a width of around 5 nm, and consisted of single particle strings. The loop formation depended on the density of the DODAC monolayers, but not on the size distribution of the particles.
An All-solid-state Lithium Battery with Sulfur as Positive Electrode Materials
Authors: Machida Nobuya , Shigematsu Toshihiko 
Published: March 2004

Abstract
An all-solid-state lithium battery was assembled with sulfur as positive electrode materials and with an inorganic solid electrolyte a-60Li2S·40SiS2 (mol %). The all-solid-state lithium battery showed successive reversibility with large specific capacity. The specific capacity calculated on the base of the mass of sulfur was more than 1000 mA·h·g−1.
A Facile and Novel Route to 99mTc-labeled Antimony Sulfide Nanocolloid
Authors: Park Sang Hyun , Choi Sang Mu , Gwon Hui Jeong , Park Kyung Bae 
Published: March 2004

Abstract
99mTc-labeled antimony sulfide nanocolloid was prepared by a new labeling method that involves room temperature reconstitution with Na99mTcO4. Transmission electron microscope showed that the mean particle size was estimated to be mostly 7–15 nm. The labeling yield of 99mTc-Sb2S3 was more than 99%. The stability of the labeled product was studied at room temperature and it was found to be excellent.
Structures and Magnetic Properties of Organic Biradical Compounds with an Aromatic Core and Long Alkyl Groups
Authors: Amano Takamitsu , Akutsu Hiroki , Yamada Jun-ichi , Nakatsuji Shin’ichi 
Published: March 2004

Abstract
Organic biradical compounds having a biphenyl or naphthalene core and long alkyl groups with TEMPO (2,2,6,6-tetramethyl-1-piperidinyloxy) radicals at their ends were found to show moderately strong antiferromagnetic interactions, being based on the singlet-triplet model. The behavior could be understood by considering the structures as being assembled in a “hand-in-hand” fashion.
Intramolecular (2π + 2π) Photocycloaddition of Styrenes Tethered by Siloxanes
Authors: Maeda Hajime , Yagi Hiroaki , Mizuno Kazuhiko 
Published: March 2004

Abstract
Intramolecular (2π + 2π) photocycloaddition of styrenes tethered by flexible siloxane chains gave the corresponding cyclobutacyclophanes in high yields. Triplet-sensitization was found to be effective for the photocycloaddition.