bluuebunny/crossref_metadata_2025_split huggingface dataset:
Quantum dynamics in high‐spin molecules, spin dendrimers, and spin lattices
Authors: Takahata Masahiro , Shoji Mitsuo , Nitta Hiroya , Takeda Ryo , Yamanaka Shusuke , Okumura Mitsutaka , Nakano Masayoshi , Yamaguchi Kizashi 
Published: September 2005

AbstractWe perform spin dynamics in strongly correlated electron–spin systems to clarify the relationship between the phase relaxation and the structure of the spin systems. The interaction among spins is considered to be Heisenberg‐type exchange. The quantum Liouville approach is used for the dynamics involving the relaxation processes of the systems, which is considered to originate in spin–phonon and electron spin–nuclear spin interactions. As a first step of our study, to examine the effects of the structures on the phase relaxation, we consider the phenomenological relaxation parameters for the relaxation terms of quantum Liouville equation, and perform the spin dynamics in four types of four electron–spin systems that have linear, square, star (dendritic structure), and tetrahedral structures. The results of our calculation indicated the possibility for the control of the phase relaxation by the change of the structure in spin clusters. Possible implications of our results are related to the single‐molecule magnets, ESR‐STM detection of spins, and related spin‐transition phenomena (decoherence and population relaxation). © 2005 Wiley Periodicals, Inc. Int J Quantum Chem, 2005
Highly sensitive high‐performance liquid chromatography/selective reaction monitoring mass spectrometry method for the determination of cyclophosphamide and ifosfamide in urine of health care workers exposed to antineoplastic agents
Authors: Sottani Cristina , Tranfo Giovanna , Faranda Paolo , Minoia Claudio 
Published: September 2005

AbstractIn recent years, the potential for exposure of health care workers to antineoplastic agents has led to the establishment of more restrictive government and professional standards and procedures for handling cytotoxic drugs. Therefore, the detection of low exposure levels is a new and important aim of biological monitoring. In the present paper we report an assay for the simultaneous determination of cyclophosphamide (CP) and ifosfamide (IF) in urine, using electrospray ionization liquid chromatography/tandem mass spectrometry with selective reaction monitoring (HPLC/SRM‐MS). A rapid sample preparation procedure uses a solid‐phase extraction stage with C18 columns. The urine assay is linear over the range 0.02 to 0.4 µg/L, with lower limits of quantification (LLOQs) of 0.02 and 0.04 µg/L for CP and IF. The accuracy and precision have been carried out through the validation study. The intra‐day precision, expressed as relative standard deviation (RSD), is found to be always less than 14.7% for both analytes. The overall precision, assessed on three different days, is less than 15.0%. The recovery of ozaxaphosphorines ranges from 83.5% (CP) to 88.5% (IF) with a RSD always less than 14.6%. The uncertainty of the overall method was also evaluated, to identify possible sources of error. The combined uncertainty was less than 25% over all the days of the validation study. This method is selective and sensitive enough to determine trace levels of CP and IF in a range of urine concentrations relevant to performing low exposure assessment. Copyright © 2005 John Wiley & Sons, Ltd.
Complementary use of Fourier transform laser microprobe mass spectrometry and time‐of‐flight static secondary ion mass spectrometry for the study of the surface adsorption of organic dyes on silicate materials
Authors: Busuioc Alina‐Maria , Mondt Roel De , Moisio Harri , Cool Pegie , Vasile Aurelia , Bilba Nicolae , Vansant Etienne , Vaeck Luc Van 
Published: September 2005

AbstractThe adsorption of organic ionic dyes on different pore size engineered silica materials with potential application for industrial wastewater treatment has been investigated using Fourier transform laser microprobe mass spectrometry (FT‐LMMS) and time‐of‐flight secondary ion mass spectrometry (TOF‐S‐SIMS). The complementary use of the two methods with different information depth allowed data on the subsurface distribution and pore penetration of the adsorbed organic compounds. Macroscopic methods were employed to determine the amount adsorbed on the particles and the specific external surface area. Local MS analysis allows identification of the organic dyes exclusively at the outer particle surface when the pore size is inferior to the size of the adsorbing molecule, or at the surface of the channels inside the material. Specifically, the monolayer information depth of TOF‐S‐SIMS causes a signal to refer essentially to the adsorbate at the outer particle surface, which is only a fraction of the total adsorption in mesoporous materials, while FT‐LMMS allowed detection of the presence of adsorbates at the outer surface as well as inside the subsurface of 10 to 50 nm depending on the material under study. The observed data open perspectives for the molecular monitoring of the adsorption behaviour of different materials at the (sub) µm scale. Copyright © 2005 John Wiley & Sons, Ltd.
Multi‐residue liquid chromatography/tandem mass spectrometric analysis of beta‐agonists in urine using molecular imprinted polymers
Authors: Van Hoof Nathalie , Courtheyn Dirk , Antignac Jean‐Philippe , Van de Wiele Mieke , Poelmans Sofie , Noppe Herlinde , De Brabander Hubert 
Published: September 2005

AbstractIon suppression, a matrix effect that affects quantitative mass spectrometry, is one of the main problems encountered in liquid chromatography/tandem mass spectrometry. Two different clean‐up steps for the multi‐residue analysis of beta‐agonists in urine were evaluated with respect to minimisation of ion suppression, namely, a mixed‐phase solid phase extraction (SPE) column, i.e., clean screen Dau (CSD), and a molecular imprinted polymer (MIP) SPE column. Ion suppression experiments revealed that CSD sample clean‐up can lead to false negative results for some beta‐agonists, and that clean‐up using MIP columns is more selective for beta‐agonists than the use of CSD columns. Copyright © 2005 John Wiley & Sons, Ltd.
Refinements to the diastereoisomer‐specific method for the analysis of hexabromocyclododecane
Authors: Tomy Gregg T. , Halldorson Thor , Danell Robert , Law Kerri , Arsenault Gilles , Alaee Mehran , MacInnis Gordia , Marvin Chris H. 
Published: September 2005

AbstractThe emergence of hexabromocyclododecane (HBCD) as a bromine‐based flame retardant of concern is partly attributable to recent measurements on the environmental occurrence of the individual diastereoisomers (α, β and γ). These measurements were fuelled by a newly developed liquid chromatography/tandem mass spectrometric (LC/MS/MS)‐based analytical method. However, in the course of our recent studies on the environmental fate and behaviour of the diastereoisomers of HBCD, some interesting features of the LC/MS/MS method became apparent. For example, the ion signal of the native ions was found to be dependent on the final extract volume. This was true for both biotic and sediment samples and was found to arise from the suppression of the ion signal due to endogenous material in the extracts that escape clean‐up. We have also found differences in the stability of the diastereoisomers in different solvents. If left unaccounted for, both factors can compromise analytical measurement data. By way of a series of controlled experiments conducted at our two laboratories [Department of Fisheries & Oceans Canada (DFO) and Environment Canada (EC)], we illustrate these features and demonstrate that use of newly synthesized labelled HBCD isomers [(13‐carbon (13C) and deuterium (d18)] can minimize and often circumvent matrix‐related effects. Copyright © 2005 John Wiley & Sons, Ltd.
On‐line pretreatment using methylcellulose‐immobilized cation‐exchange restricted access media for direct liquid chromatography/mass spectrometric determination of basic drugs in plasma
Authors: Kawano Shin‐ichi , Takahashi Masatoshi , Hine Takashi , Yamamoto Eiichi , Asakawa Naoki 
Published: September 2005

AbstractA novel methylcellulose‐immobilized restricted access media column with strong cation‐exchange groups on an internal surface (MC‐SCX) was evaluated for the direct injection analysis of basic polar drugs in plasma by column‐switching liquid chromatography/mass spectrometry (LC/MS). Analytical conditions, including an automated pretreatment step and MS detection, were optimized for a series of basic drugs (doxepin, desipramine, imipramine, nortriptyline, amitriptyline, clomipramine). On‐line pretreatment with the MC‐SCX column followed by fast gradient analysis using a C18 column resulted in a total analysis cycle time of 7 min for each spiked plasma sample. More than 150 plasma samples spiked with target compounds were measured without compromising MS detection (relative standard deviations less than 11% for all compounds, and regression coefficients greater than 0.99). Copyright © 2005 John Wiley & Sons, Ltd.
Effect of Hydrothermal Treatment on Formation and Structural Characteristics of Slowly Digestible Non‐pasted Granular Sweet Potato Starch
Authors: Shin Sang Ick , Kim Ho Jong , Ha Hyo Jeong , Lee Seung Hee , Moon Tae Wha 
Published: September 2005

AbstractThe formation and structural characteristics of slowly digestible non‐pasted granular starch in sweet potato starch were investigated under various hydrothermal treatment conditions. The moisture content of the sweet potato starch was adjusted to 20, 50 or 90%, and the starch was heated at 40, 55 or 100°C for 12 h in a dry oven. The relative crystallinity of the hydrothermally treated samples was decreased with increasing temperature, and the X‐ray diffraction patterns of the samples were altered from Cb‐type to A‐type. Microscopic observations did not reveal any changes in the starch granules of any samples except those with moisture contents of 50 and 90% that were heated at 100°C. When gelatinization parameters were examined, samples with moisture contents of 50 and 90% that were heated at 55°C and samples of all moisture contents that were heated at 100°C had peak temperatures higher than that of raw starch but gelatinization enthalpies lower than that of raw starch. The swelling factor of the samples heated at 40°C did not change significantly, whereas that of samples heated at 55 and 100°C was decreased at increased moisture levels. The sweet potato starch with 50% moisture content that was heated at 55°C had the highest content of granular slowly digestible starch, about 200% that of raw starch, although our study did not involve further hydrothermal treatment conditions. Further study is required to complete a process for more efficient production of heat stable and slowly digestible starch.
Chemical and Functional Properties of Phaseolus lunatus and Manihot esculenta Starch Blends
Authors: Novelo‐Cen Loraine , Betancur‐Ancona David 
Published: September 2005

AbstractChemical and functional characteristics were determined for Phaseolus lunatus (P) and Manihot esculenta (M) starches, and blends of these two starches (25P/75M, 50P/50M, 75P/25M (%, w/w)). Starch purity varied from 95 to 98%. The lowest amylose content was in M. esculenta (17.3%) and the highest in P. lunatus (32.4%) with the blends having intermediate values. Total dietary fiber content in M. esculenta was 1.7%, and 1.2% in P. lunatus; of the blends the 25P/75M had the highest percentage (2.3%). Initial gelatinization temperature was higher for P. lunatus (67.9°C) than for M. esculenta (57.6°C), with the blends having intermediate values. P. lunatus starch had the highest retrogradation value (8.3 mL/50 g starch) of all the starches, while M. esculenta and the 25P/75M blend had no retrogradation at all. The P. lunatus paste had the highest viscosity (125.5 mPa s) compared to the other pastes, which were statistically similar (P>0.05). Gel clarity was lower in P. lunatus (23.84%T) than in M. esculenta (51.76%T), with intermediate values in the blends. The 25P/75M blend was selected as having the best combination of characteristics, since it showed not retrogradation, had high viscosity (102 mPa s), and was stable in the heating‐cooling cycle. This makes it a starch with suitable functional properties for use in a variety of foods. These results suggest that blending native starches from different vegetable sources improves their properties.
Cell proliferation in the cranial base of A/J mice with 6‐AN‐induced cleft palate
Authors: Long Sally Y. , Larsson K. Sune , Lohmander Stefan 
Published: September 2005

AbstractMidsagittal sections of the heads of day 14.5–15.0 control A/J mouse fetuses revealed three areas of rapidly growing cartilage in the cranial base:mesethmoid, presphenoid, and craniopharyngeal. There was a curvature in the presphenoid, which straightened by the time of palatine shelf movement In fetuses of females treated with 6‐aminonicotinamide (6‐AN) on gestation day 13 the presphenoid had not straightened by day 15.5 and these fetuses all had cleft palate. In nontreated mice with spontaneous cleft lip and palate the presphenoid straightening was not impaired. Autoradiographs of [3H] thymidine uptake in the cranial base of experimental fetuses revealed selective impairment of cell proliferation in the presphenoid as judged by a significant decrease in labeled nuclei. It is proposed that straightening of the presphenoid is necessary for palatine shelf movement and normal palate closure.
Estimation of hydrocortisone dose and optimal gestation period for cleft palate induction in golden hamsters
Authors: Chaudhry A. P. , Shah R. M. 
Published: September 2005

AbstractThirty milligrams of hydrocortisone administered im to pregnant golden hamsters at gestation day 10:20 (i.e., 10 days, 20 h postconception), 11:00, or 11:04 produced 91, 100, and 100% cleft palate, respectively. Smaller doses (15, 20, or 25 mg) produced higher incidences of cleft palate at day 11:00 than 10:20 or 11:04, indicating that day 11:00 is the optimal time for yield of cleft palate with this system.
Strain differences in susceptibility to the teratogenic effect of acetazolamide in mice
Authors: Green Margaret C. , Azar Catherine A. , Maren Thomas H. 
Published: September 2005

AbstractIntraperitoneal administration of acetazolamide to pregnant female mice on day 9 or 10 of gestation (750 mg/kg given twice, at 10 AM and 4 PM) produced postaxial abnormalities of the forelimbs with high frequency in the CBA/J and C57BL/6J strains, intermediate frequency in A/J and DBA/2J, and low frequency in C3H/HeJ and SWR/J. CBA/J was most susceptible to treatment on day 10, A/J on days 9 and 10, and C57BL/6J and C3H/HeJ on day 9. There was no reduction in amount of amniotic fluid 4 h after the last injection.
Spatial relations in the oral cavity of cortisone‐treated mouse fetuses during the time of secondary palate closure
Authors: Greene R. M. , Kochhar D. M. 
Published: September 2005

AbstractCortisone has long been used experimentally to induce cleft palate in mice, but the mechanisms by which it causes this effect remain controversial. It has been repeatedly demonstrated that after administration of cortisone the movement of the palatal shelves from a vertical to a horizontal position is delayed. The long‐accepted hypothesis is that during this delay growth of the head continues so that when the palatal shelves finally do become horizontal they are too far apart to meet in the midline and fuse. We found that maternally administered cortisone induced 95% cleft palate in ICR/DUB mouse fetuses observed at days 15–18 of gestation. Observations made on frozen, cryostat‐cut sections of fetal heads during the time of palate closure indicated that shelf elevation in experimental animals was delayed by as much as 12–14 h. However, when the shelves finally reached the horizontal they made contact with both the nasal septum and each other. It seems therefore that cortisone, beside causing delay in self movement, may also interfere with processes that occur subsequent to horizontalization leading to shelf fusion.
The effect of thalidomide intake during 113 human pregnancies
Authors: Kajii T. , Kida M. , Takahashi K. 
Published: September 2005

AbstractThalidomide was taken by 113 pregnant women during August 1959 to December 1961. Of these, only seven women took the drug during the critical period, i.e., between the 34th and 50th day after the last menstrual period. Three of them delivered malformed babies, including one spontaneously aborted by the 101st day after the last menstrual period. The remaining four women had children without apparent malformations. Two of the four children were reexamined by the age of 11 years. Rentgenograms were taken of the entire skeleton, and no malformation attributable to thalidomide was found. The first day of thalidomide intake in these four cases ranged from the 46th–49th day after the last menstrual period. It seems that a “thalidomide‐resistant pregnancy” occurred in some of the cases in which the drug was taken only by the 46th day or later in the critical period. In the case of two other women, thalidomide was taken earlier than the critical period: one by the 19th day and the other by the 23rd. The former underwent an induced abortion, and the latter had a spontaneous abortion by the 49th day. In the remaining 104 cases, in which thalidomide was prescribed later than the critical period, the offspring were apparently normal, except for one case of anal stenosis.
Teratogenic effects of carcinogen implantation in a regenerative field in Bufo arenarum tadpoles
Authors: Matos Elena L. , De Lustig Eugenia S. 
Published: September 2005

AbstractImplantation of 20‐methylcholanthrene (MC), 3,4 benzopyrerne (BP), and 7,12‐dimethylbenz [a] anthracene in the tail of Bufo arenarum tadpoles induced toratogenic effects as well as lymphocyte or pleomorphic cell nodule formation. The development of nodules was modified by a regenerative field. The incidence and intensity of the teratogenic effects (supernumerary fins, accessory notochords—the latter reported here for the first time in amphibia) were enhanced by a regenerative field caused by tail amputation. MC and BP produced only supernumerary fins, and did so infrequently; whereas DMBA produced both defects, and in relative large frequencies.
Incorporation of a phospholipid precursor into the subcellular organelles of 9‐methylpteroylglutamic acid‐treated rat embryos
Authors: Chepenik Kenneth P. , Waite B. Moseley 
Published: September 2005

AbstractPregnant Long‐Evans rats were fed a synthetic diet lacking folic acid and containing 9‐methylpteroylglutamic acid on the llth day of gestation and then fed a complete diet beginning on the 14th day. Treated and untreated pregnant rats injected with 10 μCi of [14C] ethanolamine on the 12th or 14th day of gestation were killed on the 14th, 15th, or 16th day. The total radioactivity and radioactivities of phosphatidylethanolamine (PE), phosphatidylcholine (PC), and lysophosphatidylethanolamine (LPE) were determined in chloroform extracts of homogenates and subcellular fractions prepared from whole emhryos on the designated days of gestation. The specific radioactivity of phospholipids extracted from the lysosomal‐rich fraction of treated embryos was twice that of controls but the phospholipid‐specific radioactivity of the low‐speed fraction from treated embryos was one‐half of that of controls on the 14th day. The relative distribution of radioactivity in PE and PC extracted from subcellular organelles of either treated or untreated embryos suggested a precursor‐product relation. The conversion of radiolabeled PE to PC seemed to occur faster in almost all subcellular fractions of the treated embryos and did not occur in the same temporal order from fraction to fraction as was found for untreated embryos. These data were interpreted to mean that the teratogen (1) stimulated lysosomal synthesis and depressed nuclear synthesis, (2) perturbed intraembryonic transmethylation of PE to lecithin, perhaps shifting the embryo to a greater dependence on placental metabolism or transport, and (3) disturbed the chemical composition of various intraernbryonic subcellular membranes.
The influence of single or fractionated doses of 5‐fluoro‐2′‐deoxycytidine teratogenicity in mice
Authors: Sasaki Hiroshi , Ohmori Kazuo 
Published: September 2005

Abstract5‐fluoro‐2'‐deoxycytidine (FCdR) was administered ip to pregnant
ICR‐JCL mice on days 7 to 12 of pregnancy either at a single dose of 1.5 mg/kg or
five fractionated doses of the same total amount at 3‐h intervals. The fraction‐
ated injections resulted in much stronger teratogenic effects than single injection
on days 9, 10, and 11 of pregnancy. Embryocidal effects of fractionated injections
were more severe than single injection on days 9 and 10 of pregnancy. The mal‐
formation frequency produced by fractionated injection was at least equivalent to
single doses of 7.5 mg/kg when the drug was given on day 9 of pregnancy.
Growth discrepancy in twins in the first trimester of pregnancy
Authors: Salomon L. J. , Cavicchioni O. , Bernard J. P. , Duyme M. , Ville Y. 
Published: September 2005

AbstractObjectiveThe prevalence and significance of intertwin growth discrepancy in the first trimester of pregnancy are controversial. The aim of this study was to refine the incidence and outcome of this discrepancy in relation to dating of the pregnancy and other biometric parameters.MethodsThis prospective study of twin pregnancies initially evaluated at 11–14 weeks' gestation was conducted between 2001 and 2004. Differences in crown–rump length (CRL) and estimated gestational age (GA) were calculated for each twin pair and their distribution was analyzed according to chorionicity and mode of conception (spontaneous or following assisted reproductive technologies). CRL‐based GA and actual GA were compared. Other biometric parameters were also compared for each twin pair. The distribution of discrepancies was analyzed according to pregnancy outcome.ResultsA total of 182 twin pregnancies was included. The mean ± SD discrepancy in CRL was 3.4 ± 3.18 mm or 5.1 ± 4.69% and the 95th centile was 9.8 mm or 14.3%. There was no influence of chorionicity (P = 0.44), mode of conception (P = 0.18) and no relation with outcome (P = 0.54). In conceptions resulting from assisted technology, the measured CRL of the smaller twin was closer to the actual GA. Cephalic and abdominal biometric measurements were significantly greater in the twin with the smaller CRL (P < 0.05). The two cases with a discrepancy >15 mm were affected by trisomy 18 and triploidy, respectively.ConclusionsCRL discrepancy in twin pregnancies in the first trimester is a frequent finding. Discrepancy >95th centile indicates major growth delay of one twin, which could indicate the presence of aneuploidy. For milder degrees of discordance the CRL of the smaller fetus is a more accurate estimate of the actual GA. Copyright © 2005 ISUOG. Published by John Wiley & Sons, Ltd.