bluuebunny/crossref_metadata_2025 huggingface dataset:
Quantification and localization of expression of the retinoic acid receptor‐β and ‐γ mRNA isoforms during neurulation in mouse embryos with or without spina bifida
Authors: Mao Gloria E. , Collins Michael D.
Published: December 2002

Background

Previous studies observed that retinoic acid receptor‐gamma (RARγ) is expressed in the open caudal neuroepithelium but that RARβ is expressed in the closed neural tube. Furthermore, retinoic acid (RA) induces RARβ expression, a molecular event associated with neural tube closure, but treatment with RA at the appropriate gestation time causes failure of neural tube closure. Since there are four isoforms of RARβ, perhaps the isoforms expressed in the closed neural tube and induced by RA are different. To investigate the hypothesis that the switch from RARγ to RARβ is mechanistically linked to neural tube closure, this study determined the concentrations and distributions of RARβ and RARγ isoforms in mouse embryos with RA‐induced neural tube defects and in splotch (Sp) mutant embryos with spina bifida.

Methods

Absolute concentrations of RARβ and RARγ isoforms were determined throughout primary neurulation (gestational day 8.5–10.0) in treated or untreated C57BL/6J mouse whole embryos by ribonuclease protection analysis. Treatment consisted of an oral dose of 100 mg/kg of all‐trans‐RA on gestational day 8.5. Spatial distributions of RARβ and RARγ were examined in RA‐treated and Sp mutant embryos by in situ hybridization.

Results

RARβ2, γ1, and γ2 were expressed in untreated embryos and were induced 4.5‐, 1.6‐, and 4.0‐fold, respectively, 4 hr after treatment with RA. In embryos with RA‐induced spina bifida, RARβ2 was expressed in the closed neural tube while RARγ1 and RARγ2 were expressed in the open caudal neuroepithelium. In splotch mice with spina bifida, the boundary between RARβ and RARγ did not correspond to the site of neural tube closure.

Conclusions

In RA‐treated embryos, the relationship between RARβ expression in the closed and RARγ in the open caudal neuroepithelium was not altered. However, in splotch embryos with spina bifida, the juncture between RARβ and RARγ expression remained in the same anatomical position in the neuroepithelium irrespective of the neural tube closure status and suggests that the switch from RARγ to RARβ expression in the closing caudal neuroepithelium may not be causally linked to neural tube closure in the splotch mutant. Teratology 66:331–343, 2002. © 2002 Wiley‐Liss, Inc.
Diprosopus: A unique case and review of the literature
Authors: Wu June , Staffenberg David A. , Mulliken John B. , Shanske Alan L.
Published: December 2002

Background

We present a case of partial facial duplication in a male infant.

Methods

The clinical, radiological, and laboratory findings for this patient are described, followed by a review of the literature.

Results

Craniofacial duplication is a rare form of conjoined twinning and presents in a wide spectrum, from dicephalus to diprosopus to partial facial duplication. Many of these cases can be diagnosed prenatally. Prenatal assessment of our patient revealed only agenesis of the corpus callosum.

Conclusions

The pathogenesis is believed to involve duplication of the notochord. Where there are more severe associated anomalies, the prognosis is poor. Partial facial duplication, as in our case, is associated with fewer anomalies, and the prognosis is better. Symmetry and an excess of tissue, rather than deficiency, favor a positive result. Teratology 66:282–287, 2002. © 2002 Wiley‐Liss, Inc.
Dose and litter allocations in the design of teratological studies for detecting hormesis
Authors: Hunt Daniel
Published: December 2002

Background

Hormesis is being recognized in the field of toxicology due to the stimulating effects of some toxic compounds at low exposure levels. Therefore, it is desirable that experimental designs for toxicological studies be flexible enough to aid in the detection of hormetic effects. Current designs may still not have enough power to do this.

Methods

A simulation study was conducted to determine teratological study designs that would yield more power over standard designs in detecting hormesis. Developmental toxicity endpoints of interest are the number of dead/resorbed or malformed fetuses in a litter. The simulation designs mimic teratological experiments in terms of sample size and number of dose levels. Modified designs with even dose spacing at low levels and reallocated litters are investigated to determine the power of hormetic detection.

Results

Designs with reallocated litters (with more litters at low exposure levels than at high levels) and even dose spacing have more power than those with equal litters per group and uneven dose spacing.

Conclusions

Through appropriate modifications of current experimental designs, such as reallocation of litters and even dose spacing, we can better detect hormetic effects. Teratology 66:309–314, 2002. © 2002 Wiley‐Liss, Inc.
Timing of prenatal care initiation and risk of congenital malformations
Authors: Carmichael Suzan L. , Shaw Gary M. , Nelson Verne
Published: December 2002

Background

Although previous studies provide some evidence that timing of prenatal care initiation is associated with risks of congenital malformation, the issue has not previously been examined in depth. This study uses data from a large population‐based registry to explore the association of timing of prenatal care initiation with risks of selected congenital malformation phenotypes.

Methods

Data on cases were grouped according to four‐digit malformation codes of the International Classification of Diseases, Ninth Revision (ICD‐9). A randomly selected group of 10,000 nonmalformed deliveries served as the comparison group. Information on month of initiation of prenatal care (categorized as during months 1–3 of gestation, months 4–7, or after month 7) and other maternal characteristics were derived from vital statistics data.

Results

Among the 176 four‐digit ICD groupings, 67 had an adjusted odds ratio for at least one of the two prenatal care categories that was either ≤ 0.67 or ≥ 1.50. Later prenatal care initiation was associated with risk ≥ 1.50 for most groups. Later care was associated with risk ≤ 0.67 for only two groups, and the effects were imprecise. Statistical interaction between parity and prenatal care was indicated for 13 groups (P < 0.10). Risks among women with no previous pregnancy tended to increase with later prenatal care initiation; risks among parous women tended to be somewhat weaker. In general, associations applied to a wide range of malformation groups.

Conclusions

This is the first large‐scale study of the association of timing of prenatal care initiation and congenital malformation risks. Further defining the phenomena that surround prenatal care as a marker may help clarify the etiologies of a variety of malformations. Teratology 66:326–330, 2002. © 2002 Wiley‐Liss, Inc.
Characterization of aquifer heterogeneity using indicator variables for solute concentrations
Authors: Wilson Amy , Rubin Yoram
Published: December 2002

A new approach to the use of tracer test concentration data for inference of the parameters characterizing the hydraulic conductivity heterogeneity is introduced. Rather than using concentration data directly, the concentrations are transformed into indicator variables, whose time‐dependent mean and covariance structure in a control plane orthogonal to the mean flow direction are developed in terms of the log conductivity variance, vertical and horizontal correlation lengths, and the mean flow velocity. Parameter values can be inferred by comparison of the theoretical indicator moments with field measurements. The approach is found to have several advantages over the direct use of concentrations. These include (1) insensitivity of the indicator covariance to the log conductivity variance, allowing for independent determination of the integral scale in isotropic media, and (2) less susceptibility to measurement errors or interference from ambient groundwater concentrations. Also, because the indicator records only the first concentration detect, it is more efficient than methods such as travel time moment analysis, which require the entire breakthrough record.
Using Moderate Resolution Imaging Spectrometer (MODIS) to calibrate advanced very high resolution radiometer reflectance channels
Authors: Heidinger Andrew K. , Cao Changyong , Sullivan Jerry T.
Published: December 2002

A series of 10 advanced very high resolution radiometers (AVHRRs) flown on National Oceanic and Atmospheric Administration (NOAA)'s polar‐orbiting satellites for over 20 years has provided data suitable for many quantitative remote sensing applications. To be useful for geophysical research, each radiometer must be accurately calibrated, which poses problems in the AVHRR reflectance channels because they have no onboard calibration. Previous studies have shown that values of the reflectance channel calibrations, accurately measured during preflight, change abruptly immediately after launch and then change slowly during the satellite's lifetime. The presence of the dual‐gain reflectance channels on the current series of AVHRRs also complicates the application of previous calibration techniques. A technique is presented here for calibrating the AVHRR dual‐gain reflectance channels using Moderate Resolution Imaging Spectrometer (MODIS) data. This method employs selective criteria to reproduce a laboratory type calibration where instrument counts observed by AVHRR are matched to reflectances measured by MODIS on a pixel by pixel basis for coincident and co‐located scenes. Unlike AVHRR, MODIS employs onboard calibration of its reflectance channels. The goal here was to explore the utility of using MODIS to calibrate the new dual‐gain reflectance channels of the AVHRR. The AVHRRs in the NOAA‐KLM series of spacecraft employ a dual‐gain approach to increase the sensitivity to dark scenes. Traditional methods using radiometrically stable targets to calibrate the reflectance channels of AVHRR typically do not provide data for both gain settings. The data from two scenes that met the over‐pass criteria are analyzed. The regression of the MODIS reflectances versus the AVHRR counts for these scenes were able to produce calibration slopes and intercepts in both the low and high gain regions. The reflectance differences using the MODIS‐derived calibration compared to preflight calibration are well within the expected behavior of the AVHRR during its first year in orbit. Comparison with reference ch1 and ch2 reflectance values from NOAA 9 for a Libyan Desert Target were within 5% of those using the MODIS‐derived calibration. While the determination of the absolute accuracy this approach needs further study, it clearly offers the potential for calibration of the AVHRR dual‐gain reflectance channels.
Interfield and intrafield variability of methyl halide emissions from rice paddies
Authors: Redeker K. R. , Andrews J. , Fisher F. , Sass R. , Cicerone R. J.
Published: December 2002

Methyl halide gases are important sources of atmospheric inorganic halogen radicals. We measured methyl halide emissions from three rice fields over two full growing seasons. Rice paddy emissions of methyl chloride, methyl bromide and methyl iodide are insignificant until field flooding. Rice growth stage determines methyl bromide and methyl iodide emissions while methyl chloride emissions are comparable between planted and unplanted plots. Houston, Texas, and Maxwell, California, field integrated seasonal fluxes of methyl chloride, methyl bromide and methyl iodide are consistent (values range from 2.3 to 3.9, 0.8 to 1.1, and 28.1 to 62.0 mg m−2, respectively) despite differences in multiple field parameters. We also examined field emission variability using 12 chamber placements. Methyl bromide and methyl iodide emissions within homogenous rice paddies require at least three replicates to determine field mean fluxes within 20%, and for methyl chloride emissions, over 10 replications per field are necessary.
High‐latitude pump‐induced optical emissions for frequencies close to the third electron gyro‐harmonic
Authors: Kosch M. J. , Rietveld M. T. , Kavanagh A. J. , Davis C. , Yeoman T. K. , Honary F. , Hagfors T.
Published: December 2002

It has been long established that high‐power O‐mode HF pumping of the ionosphere can produce artificial optical emissions. 630 nm O(1D) photons are produced by pump‐accelerated electrons colliding with the F‐layer neutral oxygen. However, the mechanism for artificial electron acceleration remains unclear. Competing theories include Langmuir and upper‐hybrid turbulence. Pump‐induced HF coherent radar backscatter power is closely linked with upper‐hybrid turbulence, both of which are known to reduce when pumping on an electron gyro‐harmonic frequency. On 3 November 2000, the EISCAT HF facility was systematically stepped in frequency through the 3rd gyro‐harmonic. A significant reduction in the artificial optical intensity coincides with that of CUTLASS radar backscatter power. This is conclusive proof that upper‐hybrid turbulence is intimately linked to the mechanism for high‐latitude pump‐induced aurora, at least for 630 nm photons and the steady state.
Influence of coastal fronts on near‐inertial internal waves
Authors: Davies Alan M. , Xing Jiuxing
Published: December 2002

A numerical model, with a coastal boundary and near shore surface or bottom front is used to examine the role of the coast and front upon the generation and propagation of wind induced near‐inertial internal waves. When stratification extends to the coast, near‐inertial internal waves are produced at the coastal boundary. However when the near shore region is well mixed, the source of near‐inertial internal wave production is the front. Near‐inertial internal waves generated on the positive vorticity side of the front, propagate away in the horizontal. Those generated on the negative vorticity side are trapped although some vertical propagation occurs. When a coastal boundary is included significant inertial currents are found at depth phase shifted by 180° from the surface. This goes some way to explain the recent observed distributions of inertial energy found in near coastal measurements.
EXCITED TAU LEPTON CONTRIBUTION TO W → τντ DECAY AT THE ONE-LOOP LEVEL
Authors: DIAZ RODOLFO A. , MARTINEZ R. , SAMPAYO O. A.
Published: December 2002

We evaluate the compositeness effects of tau lepton on the vertex Wτντ in the context of an effective Lagrangian approach. We consider that only the third family is composed and we get the corrections to the non-universal lepton coupling gτ/ge. As the experimental bounds on non-universal lepton couplings in W decays are weak, we find that the contributions of the excited particles do not give realistic limits on the excited mass, since they lead to Λ < m*.
D-BRANES, TACHYONS AND K-HOMOLOGY
Authors: SZABO RICHARD J.
Published: December 2002

We present an overview of the ways in which D-brane charges are classified in terms of K-theory, emphasizing the natural physical interpretations of a homological classification within a topological setting.
DECOUPLING SOLUTION TO SUSY FLAVOR PROBLEM VIA EXTRA DIMENSIONS
Authors: HABA NAOYUKI , MARU NOBUHITO
Published: December 2002

We discuss the decoupling solution to SUSY flavor problem in the fat brane scenario. We present a simple model to yield the decoupling sfermion spectrum in a five-dimensional theory. Sfermion masses are generated by the overlap between the wave functions of the matter fields and the chiral superfields on the SUSY breaking brane. Two explicit examples of the spectrum are given.
PLATO'S FIRE AND THE NEUTRINO MASS MATRIX
Authors: MA ERNEST
Published: December 2002

With the accumulation of many years of solar and atmospheric neutrino oscillation data, the approximate form of the 3 × 3 neutrino mixing matrix is now known. The theoretical challenge is to understand where this mixing matrix comes from. Recently, a remarkable fact was discovered that for a specific pattern of the neutrino mass matrix at a high scale, any flavor-changing radiative correction will automatically lead to the desired mixing matrix. It was also discovered that the required specific pattern at the high scale can be maintained by the non-Abelian discrete symmetry A4 which is also the symmetry group of the regular tetrahedron, one of the five perfect geometric solids known to Plato who associated it with the element "fire". We discuss this recent development and add to it a new and very simple mechanism for the implementation of the flavor-changing radiative correction.
QUANTUM CORRECTIONS TO NEWTON'S LAW
Authors: WARD B. F. L.
Published: December 2002

We present a new approach to quantum gravity starting from Feynman's formulation for the simplest example, that of a scalar field as the representative matter. We show that we extend his treatment to a calculable framework using resummation techniques already well-tested in other problems. Phenomenological consequences for Newton's law are described.
LASER-INDUCED SELECTIVE CRYSTALLIZATION OF A-SiGe FILM
Authors: MA XIYING , CHEN XUEKANG , WU GAN , YANG JIANPING , LEI ZHANGXU
Published: December 2002

Laser induced pattern crystallization technique with pulsed KrF excimer (248 nm) laser was used to irradiation amorphous SiGe films prepared by plasma-enhanced chemical vapor deposition (PECVD) on Si substrates. The surface of laser treated sample was investigated by scanning electron microscopy (SEM), it was found that the film irradiated by KrF excimer composed by well-shaped square periodicity embedded in the a-SiGe matrix, and in each square there are laser induced SiGe nanocrystals. The size of SiGe crystals was estimated to be about 10 nm. The samples were analyzed by X-ray diffraction, Raman spectroscopy and photoluminescence analysis before and after crystallization. The Raman spectrum shows strong Ge-Ge, Si-Ge, and Si-Si vibrations that agree with those of crystalline Si 1-x Ge x alloy. Strong PL with two peaks at 720 nm and 750 nm was observed at room temperature in the crystallized film, whereas the uncrystallized sample emits no peaks. These results indicate that nanometer SiGe alloy were formed and laser-induced technology is an efficient technique to produce nanometer materials.
OXIDATION STUDY OF RF SPUTTERED AMORPHOUS AND POLYCRYSTALLINE SILICON GERMANIUM FILMS
Authors: LEOY C. C. , KAN EWH , ARIANTO J. , CHOI W. K. , WEE A. T. S. , LIU Y. J.
Published: December 2002

Oxidation study of rf sputtered amorphous and polycrystalline silicon germanium ( Si 1-x Ge x ) film which was conducted using infrared spectroscopy (FTIR). The oxidation results showed linear oxidation rate of amorphous Si 1-x Ge x and polycrystalline Si 1-x Ge x films in the dry oxygen ambient did not depend on the Ge concentration. We found that Ge nanocrystals were formed from mixed ( Si , Ge ) O 2 oxides when annealed in forming gas (10% H 2 + N 2) while pure N 2 showed formation of Ge clusters.
FORMATION OF GaN FILM BY AMMONIATING Ga2O3 DEPOSITED ON Si SUBSTRATE WITH ELECTROPHORESIS
Authors: YANG LI , XUE CHENGSHAN , ZHUANG HUIZHAO , LI HUAIXIANG , WEI QINQIN
Published: December 2002

The gallium nitride (GaN) films have been successfully fabricated on silicon (111) substrates through ammoniating Ga 2 O 3 films deposited by electrophoresis. The structure and composition of the formed films were characterized by Fourier transform infrared (FTIR) transmission spectroscopy, X-ray diffraction (XRD) and X-ray photoelectron spectroscopy (XPS). The results indicate that the films formed in this study are polycrystalline GaN with hexagonal wurtzite structure.
A COMPUTATIONAL DESIGN OF Si-BASED DIRECT BAND-GAP MATERIALS
Authors: MEI-CHUN HUANG , JIAN-LI ZHANG , HUI-PING LI , ZIZHONG ZHU
Published: December 2002

A bulk silicon is an indirect band gap semiconductor, the radiative transitions in silicon involves a electron-hole-phonon three-body processes and is therefore making it an inability of light emission. In order to integrate Si-based microelectronics with optical components, a best solution is to design a Si-based material with direct band-gap. Here we suggest a new Si-based superlattice consists of a nano-silicon layer and a VI-atom monolayer with dimer-structures in the interfaces between silicon and VI-atom layers. The structural formula is VI/Si m / VI/Si m / VI , (m = 2n or/and 2n+1, n ≥ 3). A simple form of (2×1) surface reconstruction has been considered in the ab initio calculation of electronic structures for this Si-based superlattices system. It is found from our computational design that a Se/Si 10/ Se/Si 10/ Se superlattice has a direct band-gap at Γ point. As a kind of new Si-based materials, the important potential and advantages in optoelectronic applications will be discussed.
STUDY ON ELECTRICAL TRANSPORT MECHANISM OF DOPED NC-SI:H FILM
Authors: WANG TIANMIN , WEI WENSHENG , XU GANGYI , ZHANG CHUNXI
Published: December 2002

Intrinsic, P-doped and B-doped hydrogenated nanocrystalline silicon (nc-Si:H) films were fabricated using plasma enhanced chemical vapor deposition (PECVD) system. It's microstructures were characterized by HRTEM. Electrical transport mechanism of nc-Si:H film was investigated: Tunneling effect of electrode/(p)nc-Si:H/(n)c-Si/electrode were electrically characterized. Electronic transport was governed by thermal-assisted tunneling within around 100K-600K and electrons hopping through the local states near the Fermi-level was existed simultaneously under 100K.
THE TRANSITION TO STEP FLOW GROWTH ON THE CLEAN AND SURFACTANT COVERED Si(111) SURFACE STUDIED BY IN-SITU LEEM
Authors: CHUNG W. F. , BROMANN K. , ALTMAN M. S.
Published: December 2002

The transition to step flow growth on the clean Si(111) (7×7), Si(111)-In [Formula: see text] and Si(111)-Sb (7×7) surfaces have been investigated using low energy electron microscopy (LEEM). The critical terrace width for step flow on the clean surface displays in Arrhenius behaviour, although with markedly different prefactor and activation energy above and below 750°K. The abrupt change in Arrhenius parameters was revealed by LEEM to correlate with the crossover from homogeneous to heterogeneous island nucleation behavior. The dependence of the critical terrace width upon step orientation is attributed to anisotropic step attachment kinetics. Sb and In surfactants were found to suppress and enhance step flow, respectively, in accordance with expectations. The preparations of Si(111)-Sb (7×7) and Si(111)-In [Formula: see text] surfaces that are morphologically suitable for step flow growth are also described.
ELECTROCHEMICAL BEHAVIOR OF AMORPHOUS HYDROUS RUTHENIUM OXIDE/ACTIVE CARBON COMPOSITE ELECTRODES FOR SUPER-CAPACITOR
Authors: ZHANG JIAN-RONG , CHEN BIN , LI WEI-KUAN , ZHU JUN-JIE , JIANG LI-PING
Published: December 2002

The RuO 2· xH 2 O/C composites were prepared directly based on a sol-gel process under ultrasonic wave (50Hz). The specific capacitance of pure RuO 2· xH 2 O materials obtained by the method reached a value of 760F/g. Physical properties of the material and electrochemical characteristics of electrodes were described.
IDENTIFY OF THE MICRO-DEFECTS IN SEMI-INSULATING GaAs
Authors: XU YUESHENG , ZHANG CHUNLING , TANG LEI , LIU CAICHI , HAO JINGCHEN
Published: December 2002

The micro-defects in semi-insulating gallium arsenide (SI-GaAs) were investigated by means of chemical etching (ultrasonic aided Abtahams-Buiocchi etching, melting KOH etching), transmission electron microscopy (TEM) and scanning electron microscopy (SEM). The experimental results showed that the micro-defects in SI-GaAs are micro-precipitates of As with the size of microns. Micro-defects and dislocations have strong interaction, dislocations absorb the micro-defects and micro-defects decorate on the dislocations.
THE EFFECT OF ANNEALING TEMPERATURES ON THE MICROSTRUCTURE OF La0.5Ca0.5MnO3 FILMS
Authors: CHEN X. M. , WANG Y. , LIU C. X. , ZHAO Y. N. , LI M. , MAI Z. H. , GONG W. Z. , ZHAO B. R. , JIA C. J. , ZHENG W. L.
Published: December 2002

La 0.5 Ca 0.5 MnO 3 (LCMO) thin films grown by pulsed laser deposition (PLD) and annealed at different temperatures were investigated by high angle X-ray diffraction, atomic force microscope (AFM), scanning electron microscope (SEM), and energy dispersive spectroscopy (SEM-EDS). The lattice parameters, surface morphology as well as the metal compositions of the films were obtained. It was found that the surface morphology of the films strongly depends on the annealing temperatures. The difference of the thermal expansion coefficients between the film and the substrate plays an important role in determining the morphology of the film surface. It induces an in-plane compressive stress in the LCMO films. The strains in the film can be relaxed by nanoscale grains and cracks.
CROSSOVER FROM RABI TO JOSEPHSON DYNAMICS IN TWO-COUPLED BOSE–EINSTEIN CONDENSATES AS A PHASE TRANSITION PROCESS
Authors: BHATTACHERJEE ARANYABHUTI , MOHAN MAN
Published: December 2002

Crossover from individual Rabi dynamics to collective Josephson dynamics in two-coupled Bose–Einstein condensates is studied as a phase transition process. We obtain the critical value of the parameter Λ (ratio of the mean field energy to the tunneling matrix element) for the π-phase oscillations from the non-linear perturbation expansion of small oscillations around the saddle point of the first-order Euclidean (imaginary time) differential equations for polar and azimuthal angles θ and ϕ without approximation.
Combination Chemotherapy and Radiotherapy for Primary Central Nervous System Lymphoma: Radiation Therapy Oncology Group Study 93-10
Authors: DeAngelis Lisa M. , Seiferheld Wendy , Schold S. Clifford , Fisher Barbara , Schultz Christopher J.
Published: December 2002

PURPOSE: Primary CNS lymphoma (PCNSL) is an aggressive primary brain tumor. Cranial irradiation alone rarely results in long-term disease control or prolonged survival. We prospectively studied the use of combination chemotherapy plus cranial irradiation in newly diagnosed patients with PCNSL.

PATIENTS AND METHODS: We enrolled 102 newly diagnosed, immunocompetent patients with PCNSL; 98 were assessable. Patients first received five cycles of methotrexate 2.5 g/m2, vincristine, procarbazine, and intraventricular methotrexate (12 mg). Whole-brain radiotherapy (RT) was administered to a total dose of 45 Gy and all patients received high-dose cytarabine after RT.

RESULTS: Fifty-eight percent of patients with measurable disease had a complete response to preirradiation chemotherapy and 36% had a partial (> 50%) response, for a 94% response rate. Median progression-free survival was 24.0 months and overall survival was 36.9 months. Age was an important prognostic factor; median survival was 50.4 months in patients younger than 60 and only 21.8 months in those aged 60 or older (P < .001). Fifty-three percent of patients had grade 3 or 4 toxicity during induction chemotherapy, half of which was hematologic. However, 12 patients (15%) experienced severe delayed neurologic toxicity, eight of whom died.

CONCLUSION: This is the first multicenter trial demonstrating improved survival with the combination of chemotherapy plus RT compared with previous reports of RT alone. A high-dose methotrexate-based regimen produced a high response rate before RT was administered. High-dose methotrexate combined with cranial irradiation is an effective therapeutic approach to PCNSL, but neurotoxicity is a delayed risk of this approach.
Randomized Phase III Study of Fludarabine Phosphate Versus Cyclophosphamide, Vincristine, and Prednisone in Patients With Recurrent Low-Grade Non-Hodgkin’s Lymphoma Previously Treated With an Alkylating Agent or Alkylator-Containing Regimen
Authors: Klasa Richard J. , Meyer Ralph M. , Shustik Chaim , Sawka Carol A. , Smith Anne , Guévin Raymond , Maksymiuk Andrew , Rubinger Morel , Samosh Martin , Laplante Suzanne , Grenier Jean-François
Published: December 2002

PURPOSE: To compare in a phase III study the safety and efficacy of fludarabine to that of cyclophosphamide, vincristine, and prednisone (CVP) in recurrent, low-grade, non-Hodgkin’s lymphoma after previous response to systemic treatment.

PATIENTS AND METHODS: Patients were randomized to fludarabine (25 mg/m2 intravenously on days 1 to 5, every 28 days) or CVP (cyclophosphamide 750 mg/m2 and vincristine 1.2 mg/m2 both intravenously on day 1 and prednisone 40 mg/m2 orally on days 1 to 5, every 21 days). The primary outcome assessed was progression-free survival (PFS); secondary outcomes included treatment-free survival (TFS), overall survival (OS), treatment-related toxicity, and quality of life (QoL) according to the European Organization for Research and Treatment of Cancer’s Quality of Life Questionnaire C-30 version 1.0 instrument.

RESULTS: Ninety-one patients were randomized, 47 to fludarabine and 44 to CVP. There was no difference in response rates, with 64% (complete response [CR], 9%) for fludarabine versus 52% (CR, 7%) for CVP (P = .72). With a median follow-up of 42 months, median PFS (11 months v 9.1 months; P = .03) and TFS (15 months v 11 months; P = .02) were superior in patients receiving fludarabine. No difference in median overall survival was detected (57 months for fludarabine v 44 months for CVP; P = .95). Three patients receiving fludarabine died of treatment-related toxicity compared with none of the patients receiving CVP. Peripheral neuropathy and alopecia were more common with CVP. Patients receiving fludarabine had higher scores for social function (P = .008); no other differences in QoL were detected.

CONCLUSION: In recurrent low-grade lymphoma, fludarabine improves PFS, TFS, and social function scores in comparison with CVP but does not improve OS.
Pyridine-containing Cholesterols as Versatile Gelators of Organic Solvents and the Subtle Influence of Ag(I) on the Gel Stability
Authors: Kawano Shin-ichiro , Fujita Norifumi , Bommel Kjeld J C van , Shinkai Seiji
Published: December 2002

New cholesterol-based gelators bearing a 4-, 3-, or 2-pyridyl group (1, 2, or 3, respectively) have been designed. Compound 1 gelled 16 of the 19 solvents tested, indicating that 1 acts as a very versatile gelator. The gelation ability of compound 2 was significantly improved by added AgOTf, owing to an Ag(I)-pyridine interaction. The findings indicate that the pyridyl group is very useful to impart new functions to organogel systems.
Synthesis of Tungsten Thienyl Complexes via C–H Bond Activation of Thiophenes
Authors: Sakaba Hiroyuki , Yumoto Takahiro , Watanabe Sanae , Kabuto Chizuko , Kabuto Kuninobu
Published: December 2002

The reactions of cis-Cp∗W(CO)2(MeCN)Me (1) with thiophene or 3-methylthiophene resulted in selective α-C–H bond activation to give cis-Cp∗W(CO)2(MeCN)R [R = 2-C4H3S (2a), 2-C4H2S-4-Me (2b)]. 2a reacted with 3-methylthiophene to afford thienyl exchange products 2b and thiophene in addition to decomposition products. Reversibility of the exchange reaction was shown by the reaction of 2b with thiophene.
Dendritic Antibody Supramolecules: Combination of IgM and IgG
Authors: Harada Akira , Yamaguchi Hiroyasu , Tsubouchi Kaori , Horita Eri
Published: December 2002

A novel antibody supramolecule was designed and prepared by using immunoglobulin M (IgM) as a core and chemically modified IgGs as branches. The dendritic supramolecules were composed by proteins with molecular weight of about 2 million and constructed by non-covalent bonds. They could bind antigens strongly with high specificity.
Stereospecific Construction of Chiral Quaternary Carbon Compounds from Chiral Secondary Alcohol Derivatives
Authors: Masaki Yukio , Arasaki Hideki , Iwata Masashi
Published: December 2002

Chiral tertiary dichloromethylcarbinol derivatives, prepared by stereospecific α C–H insertion reaction of dichlorocarbene with protected chiral secondary alcohols, were converted into intermediary α-chloroepoxides which gave stereospecifically chiral quaternary carbon compounds, α-aminoacids via α-azide-aldehydes and α-cyanoacetic acids through cyanation, respectively. The fashion generating the quaternary centers from dichloromethylcarbinols via α-chloroepoxides was proved to be quite different depending on the substrates: inversion of configuration of non-benzylic substrates and apparent retention with benzylic one.
A New Conjugated Polymer Chemosensor Functionalised with 2,6-Bis(1,3,4-oxadiazole-2-yl)pyridine for Metal Ion Recognition
Authors: Yang Nam Choul , Jeong Jae Kyun , Suh Dong Hack
Published: December 2002

A new conjugated alternative copolymer based on 2,6-bis(1,3,4-oxadiazol-2-yl)pyridine and 9,9-dialkylfluorene in a main chain showed strong blue fluorescence with band maxima at 389 nm and 405 nm in the 1,2-dichloroethane solution and posessed sensitivity to various metal ions such as Ni2+ and Fe3+ as a fluorescence-mode chemosensor.
Effect of Calcium on the Catalysis of Nickel in the Production of Crystallized Carbon from Lignocresol for Electromagnetic Shielding
Authors: Wang Xiao-Shui , Okazaki Noriyasu , Suzuki Tsutomu , Funaoka Masamitsu
Published: December 2002

Char with turbostratic structure of carbon (T-component) that could afford a practical electromagnetic shielding capacity at 50–800 MHz was produced from lignocresol added with nickel and calcium by its carbonization at 900 °C, although the addition of nickel alone gave amorphous carbon. This lignin char exceeded the corresponding char obtained from acid-demineralized alkali lignin in the shielding capacity. The formation of T-component can be accounted for by the promotion action of calcium to prevent nickel catalyst from agglomeration.
A New Chiral Host, (5S-trans)-11b-(1,1-Dimethylethyl)-2,3,5,6,11,11b-hexahydro-3-oxo-1H-indolizino[8,7-b]indole-5-carboxylic Acid Methyl Ester: Complexation by a Helical Network
Authors: Irikawa Hajime , Morinaga Masanori , Kondo Mitsuru
Published: December 2002

The title l-tryptophan derivative was found to serve as a chiral host and the formation of a helical network with one-dimensional channel was shown by the X-ray analysis of its inclusion complex with (R)-s-butyl chloride.
A Short Synthesis of Dipalmitoylphosphatidylinositol 4,5-Bisphosphate via 3-O-Selective Phosphorylation of a 3,4-Free Inositol Derivative
Authors: Han Fushe , Hayashi Minoru , Watanabe Yutaka
Published: December 2002

Dipalmitoylphosphatidylinositol 4,5-bisphosphate was conveniently synthesized via the regioselective phosphorylation of l-1,2-O-cyclohexylidene-5,6-di-O-(o-xylylene phosphoryl)-myo-inositol derived from 1,2-O-cyclohexylidene-3,4-O-(tetraisopropyldisiloxane-1,3-diyl)-myo-inositol.
Photodegradative Surfactants: Photolysis of p-Dodecylbenzyltrimethylammonium Bromide in Aqueous Solution
Authors: Itoh Yoshihiro , Yamamoto Kenji , Shirai Hirofusa
Published: December 2002

Upon UV irradiation, a benzyl-containing cationic surfactant, p-dodecylbenzyltrimethylammonium bromide, has been converted to a nonsurfactant, which can be separated from the aqueous solution by coprecipitation with CaSO4.
Extensive somatosensory innervation in infants with obstetric brachial palsy
Authors: Colon A.J. , Vredeveld J.W. , Blaauw G. , Slooff A.C.J. , Richards R.
Published: December 2002

In the pre‐operative screening of infants with obstetric brachial palsy (OBP), the results of routine electromyography are often overly optimistic when compared to the peri‐operative findings. This prompted us to include investigation of the sensory innervation of these infants using the N20 (the first cortical response to a peripheral stimulation) of the somatosensory evoked potentials (SSEP). Three to seven months after birth, SSEP were recorded at the skull after stimulation of the thumb and middle finger in infants with obstetric rupture of the upper trunk or avulsion of roots C5, C6, or C7, and in whom no clinical improvement of motor function was observed in the biceps brachii and deltoid muscles. In most infants, a normal N20 could be evoked, indicating the existence of peripheral sensory pathways. From the thumb, these sensory pathways would necessarily bypass the upper trunk and dorsal roots of spinal nerves C5 and C6, and from the middle finger bypass the middle trunk and dorsal root C7, before extending into the dorsal column and projecting toward the thalamus and cerebral cortex. These data suggest that in infancy the segmental sensory innervation of the hand is more diverse than is described in most textbooks. Clin. Anat. 16:25–29, 2003. © 2002 Wiley‐Liss, Inc.
Anatomical variations of the ten triangles around the cavernous sinus
Authors: Watanabe A. , Nagaseki Y. , Ohkubo S. , Ohhashi Y. , Horikoshi T. , Nishigaya K. , Nukui H.
Published: December 2002

The dimensions of the 10 triangles around the cavernous sinus were measured to define the anatomical characteristics of the triangles and to compare their consistency in shape and area. Twelve tissue blocks containing the bilateral cavernous sinuses and medial two‐thirds of the middle cranial fossae were obtained from Japanese adults at autopsy, fixed to a stereotactic frame, and examined with an operative microscope. The dimensions of each triangle were measured with calipers and compared, based on the same point and border. The anteromedial triangle and the superolateral (Parkinson's) triangle were more consistent in shape than the paramedial and oculomotor triangles, but the oculomotor triangle was larger in area than these other triangles. The posteromedial (Kawase's) triangle was more consistent in shape and larger than the anterolateral, lateral, and the posterolateral (Glasscock's) triangles. The anteromedial and superolateral (Parkinson's) triangles are important for the combined epi‐ and subdural approach to cavernous sinus lesions. The posteromedial (Kawase's) triangle is important for gaining access to the posterior cranial fossa from the middle cranial fossa. Clin. Anat. 16:9–14, 2003. © 2002 Wiley‐Liss, Inc.
Profile of on‐line anatomy information resources: Design and instructional implications
Authors: Kim S. , Brinkley J.F. , Rosse C.
Published: December 2002

This study is based on a review of 40 on‐line anatomy web resources compiled from sites selected from our own searches as well as sites reviewed and published by an external group (Voiglio et al., 1999, Surg. Radiol. Anat. 21:65–68; Frasca et al., 2000, Surg. Radiol. Anat. 22:107–110). The purpose of our survey was to propose criteria by which anatomy educators could judge the characteristics of the currently available web‐based resources for incorporation into the courses they teach. Each site was reviewed and scored based on a survey matrix that included four main categories: 1) site background information, 2) content components, 3) interactivity features, and 4) user interface design components. The average score of the reviewed sites was 3.3 of the total possible score of 10, indicating the limited use of computer‐based design features by the majority of sites. We found, however, a number of programs in each of the survey categories that could serve as prototypes for designing future on‐line anatomy resources. From the survey we conclude that various design features are less important than the comprehensiveness, depth, and logical organization of content. We suggest that the content should be sufficient for supporting explicitly defined educational objectives, which should target specific end‐user populations. The majority of anatomy programs currently accessible on‐line fall short of these requirements. There is a need for a coordinated and synergistic effort to generate a comprehensive anatomical information resource that is of sufficient quality and depth to support higher levels of learning beyond the memorization of structure names. Such a resource is a prerequisite for meaningful on‐line anatomy education. Clin. Anat. 16:55–71, 2003. © 2002 Wiley‐Liss, Inc.
The optimal timing of the transfer of hidden reserves in the German and Austrian tax systems
Authors: Frühwirth Manfred
Published: December 2002

The lower‐of‐cost‐or‐market principle implies that assets may be sold above book value, by which hidden reserves are disclosed. To avoid taxation of these hidden reserves, in German‐speaking countries companies are allowed to transfer them to a newly purchased asset within a fixed time period. In this paper, the optimal timing of hidden reserves transfers is developed with special attention to the term structure of interest rates and interest rate risk, and using the replicating principle known from the field of finance. The paper presents one model under certainty and, as a generalization of this model, another model under interest rate risk. In both models, the criterion used for decision‐making is the value of the right to transfer, which can be interpreted as the initial cost of a replicating/hedging strategy for tax payments saved/incurred. In the model under certainty, the net present value concept is used to derive the value of the right to transfer. The procedure used in the model under interest rate risk is a combination of flexible planning and the no‐arbitrage approach common in derivatives pricing. It is shown that the right to transfer hidden reserves with flexible timing is equivalent to an American‐style exchange option. In addition, the impact of term‐structure volatility on the value of the right to transfer is analyzed. The technique presented in this paper can also be used to solve other timing problems resulting from trade‐offs between early and late tax payments/tax benefits. Copyright © 2002 John Wiley & Sons, Ltd.
Simulation Monte Carlo methods in extended stochastic volatility models
Authors: Šimandl Miroslav , Soukup Tomáš
Published: December 2002

A new technique for nonlinear state and parameter estimation of discrete time stochastic volatility models is developed. Algorithms of Gibbs sampler and simulation filters are used to construct a simulation tool that reflects both inherent model variability and parameter uncertainty. The proposed chain converges to equilibrium enabling the estimation of unobserved volatilities and unknown model parameter distributions. The estimation algorithm is illustrated using numerical examples. Copyright © 2002 John Wiley & Sons, Ltd.
A mid‐latitude Asian circulation anomaly pattern in boreal summer and its connection with the Indian and East Asian summer monsoons
Authors: Wu Renguang
Published: December 2002

Using the NCEP–NCAR reanalysis for 1948–98, this study identifies a dominant pattern for the interannual variation of upper‐level winds over mid‐latitude Asia in boreal summer. This pattern, called the mid‐latitude Asian summer (MAS) pattern, features two anomalous anticyclones: one centred at 37.5° N, 65° E and the other at 42.5° N, 130° E. The MAS pattern significantly influences East Asian summer monsoon variability. In the positive phase of the MAS pattern, contrasting meridional wind anomalies between eastern China and Japan lead to above‐ and below‐normal summer rainfall in north China and south Japan respectively. The year‐to‐year change of the MAS pattern is related to that of the Indian summer rainfall, especially in central and northern India. Thus, the MAS pattern plays a role in connecting anomalous Indian heating with the East Asian summer monsoon variability.

The East Asian anomalous anticyclone displays a southeastward shift after the late 1970s. This results in a similar change of anomalous summer rainfall regions in East Asia. The West Asian anomalous anticyclone moves northeastward after the late 1970s. The relation of the MAS pattern with the Indian summer rainfall experienced an obvious weakening in the late 1970s. As a result, the statistical relation between the Indian and north China summer rainfall becomes weak after the late 1970s. Copyright © 2002 Royal Meteorological Society
Qualitative rainfall prediction models for central and southern Sudan using El Niño–southern oscillation and Indian Ocean sea surface temperature Indices
Authors: Osman Yassin Z. , Shamseldin Asaad Y.
Published: December 2002

In this study, the influences of El Niño–southern oscillation (ENSO) and the Indian Ocean sea surface temperature (SST) on rainfall variability in the central and the southern regions of Sudan are investigated. The investigation is conducted using 49 years of data from 12 rainfall stations. The results show that the driest years are associated with warm ENSO and Indian Ocean SST conditions. In the two regions, the correlation of the annual rainfall with the Indian Ocean SST is found to be relatively higher than that with the ENSO SST, with the Indian Ocean SST having stronger influences in the central region. The multiple correlation results indicate that both of the ENSO and Indian Ocean SSTs explain about 34% of the annual rainfall variability in the central region and 21% in the southern region. Two types of qualitative rainfall prediction model are developed for each region. One type uses the ENSO SST as input and the other uses the Indian Ocean SST. The verification results show that the Indian Ocean SST model is better than the ENSO SST model. Copyright © 2002 Royal Meteorological Society.
Analysis of quantitative trait loci that influence animal behavior
Authors: Flint Jonathan
Published: December 2002

Behavioral differences between inbred strains of mice and rats have a genetic basis that can now be dissected using quantitative trait locus (QTL) analysis. Over the last 10 years, a large number of genetic loci that influence behavior have been mapped. In this article I review what that information has revealed about the genetic architecture of behavior. I show that most behaviors are influenced by QTL of small effect, each contributing to less than 10% of the variance of a behavioral trait. The small effect of each QTL on behavioral variation suggests that the mutational spectrum is different from that which results in Mendelian disorders. Regions of DNA should be appropriately prioritized to find the molecular variants, for instance by looking at sequences that control the level of gene expression rather than variants in coding regions. While the number of allelic loci that can contribute to a trait is large, this is not necessarily the case: the analysis of selected strains shows that a remarkably small number of QTL can explain the bulk of the genetic variation in behavior. I conclude by arguing that genetic mapping has more to offer than a starting point for positional cloning projects. With advances in multivariate analyses, mapping can also test hypotheses about the psychological processes that give rise to behavioral variation. © 2003 Wiley Periodicals, Inc. J Neurobiol 54: 46–77, 2003
Molecular approaches to aggregation behavior and social attachment
Authors: de Bono Mario
Published: December 2002

In many animal species individuals aggregate to live in groups. A range of experimental approaches in different animals, including studies of social feeding in nematodes, maternal behavior in rats and sheep, and pair‐bonding in voles, are providing insights into the neural bases for these behaviors. These studies are delineating multiple neural circuits and gene networks in the brain that interact in ways that are as yet poorly understood to coordinate social behavior. © 2003 Wiley Periodicals, Inc. J Neurobiol 54: 78–92, 2003
Genetic analysis of the circadian system in Drosophila melanogaster and mammals
Authors: Stanewsky Ralf
Published: December 2002

The fruit fly, Drosophila melanogaster, has been a grateful object for circadian rhythm researchers over several decades. Behavioral, genetic, and molecular studies helped to reveal the genetic bases of circadian time keeping and rhythmic behaviors. Contrary, mammalian rhythm research until recently was mainly restricted to descriptive and physiologic approaches. As in many other areas of research, the surprising similarity of basic biologic principles between the little fly and our own species, boosted the progress of unraveling the genetic foundation of mammalian clock mechanisms. Once more, not only the basic mechanisms, but also the molecules involved in establishing our circadian system are taken or adapted from the fly. This review will try to give a comparative overview about the two systems, highlighting similarities as well as specifics of both insect and murine clocks. © 2003 Wiley Periodicals, Inc. J Neurobiol 54: 111–147, 2003