bluuebunny/crossref_metadata_2025 huggingface dataset:
Fourier Transform Infrared Microscopic Imaging: Effects of Estrogen and Estrogen Deficiency on Fracture Healing in Rat Femurs
Authors: Ouyang Hao , Sherman Pamela J. , Paschalis Eleftherios P. , Boskey Adele L. , Mendelsohn Richard
Published: April 2004

Infrared spectroscopic imaging with 6–10 μm spatial resolution was used to characterize the changes in fracture callus mineral content, carbonate content, mineral crystallinity, and collagen maturity in femurs of 3-month-old ovariectomized rats treated with estrogen (estrogen sufficiency) or vehicle (estrogen deficiency). Comparisons were also made in these animals to cortical bone at a distance from the callus. Analyses at 4, 8, and 12 weeks post fracture demonstrated that healing was accelerated in the estrogen-sufficient animals as demonstrated by increasing mineral content and collagen maturity and decreasing carbonate incorporation.
Surface Plasmon Spectral Fingerprinting of Adsorbed Magnesium Phthalocyanine by Angle and Wavelength Modulation
Authors: Zangeneh Mondona , Doan Nga , Sambriski Edward , Terrill Roger H.
Published: April 2004

A novel instrumental method for angle and wavelength modulated surface plasmon resonance (SPR) spectroscopy is applied to the problem of spectral selectivity in SPR experiments. For transparent analytes, SPR reflectivity data are reduced to a two-dimensional (2D) spectrum of resonance wavelength versus incident angle, λSPR(θ). This spectrum encodes the refractive index (RI) dispersion of the analyte and illustrates the increased SPR spectral shift per unit RI change at longer wavelengths (lower angle). For the absorbing analyte magnesium phthalocyanine (MgPc), the 2D data reduction method is complicated by the way the SPR and MgPc-based spectral peaks mix. Fresnel reflectivity models support experimental observations of spectral branching and qualitative fingerprints in the form of branched spectra, and difference reflectivity Δ R(λ, θ) contour plots are presented.
Surface-Enhanced Raman Spectroscopy as a Tool for Probing Specific Biochemical Components in Bacteria
Authors: Zeiri L. , Bronk B. V. , Shabtai Y. , Eichler J. , Efrima S.
Published: April 2004

Treatment of bacteria with silver yields intense and highly specific surface-enhanced Raman spectroscopy (SERS) spectra from various cellular chemical components located in the vicinity of the silver colloids. In particular, we demonstrate an extreme sensitivity to flavin components associated with the cell envelope and to their state of oxidation. Different spectra, possibly associated with DNA, carboxylates, and perhaps phosphates, are obtained from the soluble interior fraction of the cell.
Utilizing Three-Dimensional Fluorescence's Red-Shift Cascade Effect to Monitor Mycobacterium PRY-1 Degradation of Aged Petroleum
Authors: Sinski Joseph F. , Compton Bradley S. , Perkins B. Shea , Nicoson Michael C.
Published: April 2004

Samples of Mycobacterium PRY-1 inoculated motor oil are subjected to three-dimensional fluorescence spectroscopy to document the shifting of excitation/emission maxima as the solutions undergo serial dilutions. Effects such as self-quenching of individual polycyclic aromatic hydrocarbons (PAHs) and energy transfer between PAHs combine to produce large red-shifts in the resulting fluorescence emission spectra. This process is repeated over a series of weeks and is compared to preceding spectra to gauge the microbial degradation of the petroleum. Results show a two-fold, or 75%, PAH contaminant degradation by Mycobacterium PRY-1 over a 140-day growth period.
Quantitative Determination of Moisture in Lubricants by Fourier Transform Infrared Spectroscopy
Authors: Van De Voort F. R. , Sedman J. , Yaylayan V. , Laurent C. Saint , Mucciardi C.
Published: April 2004

This paper describes the development of a practical Fourier transform infrared (FT-IR) method for the determination of moisture in lubricants through the combined use of signal transduction and differential spectroscopy to circumvent matrix effects. The acid-catalyzed stoichiometric reaction of 2,2-dimethoxypropane (DMP) with moisture to produce acetone was used to provide IR signals proportional to the amount of moisture present in oils. Calibration standards were prepared by spiking polyalphaolefin (PAO) gravimetrically with water using dioxane as a carrier. For FT-IR analysis, standards and samples were diluted with acidified isooctane and then split, with one aliquot treated with DMP and the other with a blank reagent. The spectra of the two aliquots were collected, and a differential spectrum was obtained so as to ratio out the invariant spectral contributions from the sample. Quantitation for moisture was based on measurement of the peak height of the v(C=O) absorption of acetone at 1717 cm−1, yielding a standard error of calibration of ∼40 ppm H2O. The method was validated by standard addition of water in dioxane to PAO containing added base as well as to new and used oils. In all cases the method responded quantitatively to standard addition, the average standard error of prediction being ∼80 ppm, with the results showing only a minor dependence on the oil formulation. From an analytical perspective, the FT-IR method is both more reproducible and more accurate than Karl Fischer methods and has advantages in terms of environmental considerations, sample size, and speed of analysis as well as the variety of oil types that can be handled. Signal transduction/differential spectroscopy may have broader utility as an alternative means for the determination of low levels of moisture in complex matrices.
Carbon Nanostructure Examined by Lattice Fringe Analysis of High-Resolution Transmission Electron Microscopy Images
Authors: Vander Wal Randy L. , Tomasek Aaron J. , Street Kenneth , Hull David R. , Thompson William K.
Published: April 2004

The dimensions of graphitic layer planes directly affect the reactivity of soot towards oxidation and growth. Quantification of graphitic structure could be used to develop and test correlations between the soot nanostructure and its reactivity. Based upon transmission electron microscopy images, this paper provides a demonstration of the robustness of a fringe image analysis code for determining the level of graphitic structure within nanoscale carbon, i.e., soot. Results, in the form of histograms of graphitic layer plane lengths, are compared to their determination through Raman analysis.
Atmospheric Formaldehyde Monitoring in the Greater Houston Area in 2002
Authors: Chen Jinhai , So Stephen , Lee Hoason , Fraser Matthew P. , Curl Robert F. , Harman Thomas , Tittel Frank K.
Published: April 2004

A laser spectrometer based on difference frequency generation (DFG) was deployed for real-time long-term monitoring of HCHO concentrations at an environmental monitoring site located at Deer Park, Texas, in the Greater Houston area. Three HCHO concentration measurements were made during the periods of July 20–31 (period I), August 2–14 (period II), and August 24–September 25 (period III), 2002. In periods I and II, differences in HCHO concentrations are apparent between day and night measurements, with elevated concentrations during daylight hours. Most of the HCHO peak values are less than 20 ppbV except for two intense peaks on August 02 (∼25 ppbV) and August 04 (∼30 ppbV). The formaldehyde concentration levels in ambient air at the measurement site are produced mainly by the photochemical oxidation of volatile organic compounds (VOCs) caused by intense sunlight during periods I and II. This observation was made based on a comparison with the ozone concentration, solar radiation, temperature, relative humidity, and wind speed data obtained from the Texas Commission on Environmental Quality (TCEQ). During period III, data collected by a time-integrating wet-chemical technique are compared to the data collected by the spectroscopic instrument.
New Indicator for Optimal Preprocessing and Wavelength Selection of Near-Infrared Spectra
Authors: Skibsted E. T. S. , Boelens H. F. M. , Westerhuis J. A. , Witte D. T. , Smilde A. K.
Published: April 2004

Preprocessing of near-infrared spectra to remove unwanted, i.e., non-related spectral variation and selection of informative wavelengths is considered to be a crucial step prior to the construction of a quantitative calibration model. The standard methodology when comparing various preprocessing techniques and selecting different wavelengths is to compare prediction statistics computed with an independent set of data not used to make the actual calibration model. When the errors of reference value are large, no such values are available at all, or only a limited number of samples are available, other methods exist to evaluate the preprocessing method and wavelength selection. In this work we present a new indicator (SE) that only requires blank sample spectra, i.e., spectra of samples that are mixtures of the interfering constituents (everything except the analyte), a pure analyte spectrum, or alternatively, a sample spectrum where the analyte is present. The indicator is based on computing the net analyte signal of the analyte and the total error, i.e., instrumental noise and bias. By comparing the indicator values when different preprocessing techniques and wavelength selections are applied to the spectra, the optimal preprocessing technique and the optimal wavelength selection can be determined without knowledge of reference values, i.e., it minimizes the non-related spectral variation. The SE indicator is compared to two other indicators that also use net analyte signal computations. To demonstrate the feasibility of the SE indicator, two near-infrared spectral data sets from the pharmaceutical industry were used, i.e., diffuse reflectance spectra of powder samples and transmission spectra of tablets. Especially in pharmaceutical spectroscopic applications, it is expected beforehand that the non-related spectral variation is rather large and it is important to remove it. The indicator gave excellent results with respect to wavelength selection and optimal preprocessing. The SE indicator performs better than the two other indicators, and it is also applicable to other situations where the Beer–Lambert law is valid.
Second-Derivative Variance Minimization Method for Automated Spectral Subtraction
Authors: Loethen Yvette L. , Zhang Dongmao , Favors Ryan N. , Basiaga Sara B. G. , Ben-Amotz Dor
Published: April 2004

A new second-derivative variance minimization (SDVM) procedure is used to automatically extract spectra of a dilute component (solute) from a mixture whose spectrum is dominated by a major component (solvent). This procedure involves the subtraction of Savitzky–Golay second-derivative preprocessed pure solvent and mixture spectra by minimizing the variance of the difference spectrum. The resulting undifferentiated output spectra contain primarily features associated with the solute and/or solute-induced perturbations of the solvent. The SDVM method is found to outperform several related methods, including a previously proposed derivative minimization method, as demonstrated using 1000 randomly generated solute/solvent synthetic spectral pairs and experimental Raman spectra of dilute solutions of benzene in n-hexane and water in acetone. The former experimental solution produced SDVM difference spectra containing benzene bands with virtually no n-hexane interference, while the latter revealed water-induced shifts in acetone spectral features. Several other types of SDVM applications, such as the spectroscopic analysis of layered composites, are discussed.
Ultraviolet—Visible and Surface-Enhanced Raman Scattering Spectroscopy Studies on Self-Assembled Metalloporphyrin Films on Organic Monolayer-Modified Ultra-Thin Silver Substrates
Authors: Li Xiaoling , Xu Weiqing , Jia Huiying , Wang Xu , Zhao Bing , Li Bofu , Ozaki Yukihiro
Published: April 2004

A self-assembled monolayer (SAM) film of 5,10,15,20-tetra-( para-chlorophenyl)-porphyrin terbium (or lutetium) hydroxy compound (TbOH/LuOH) fabricated on a silver substrate premodified with a SAM of 4-mercaptopyridine (PySH) was studied by ultraviolet–visible (UV-Vis) spectroscopy and surface-enhanced Raman scattering (SERS) spectroscopy. PySH can modify the substrate and deliver its pyridyl group pointing out from the silver surface. Thus, we can investigate the effects of the central metals of the metalloporphyrins in the formation of the composite films. For the TbOH–PySH composite film, a new absorption band arising from TbOH appears at 425 nm, and a band at 512 nm due to the PySH-modified silver substrate shifts to a longer wavelength (538 nm). The results suggest that TbOH is successfully assembled on the top of PySH-modified silver film and that there is an interaction between TbOH and PySH in the film. The frequency shifts and relative intensity changes of bands due to PySH in the SERS spectra imply the coordination of the pyridyl group on Tb in the SAM. As for the LuOH–PySH composite film, its SERS spectrum shows bands arising from both the LuOH and PySH moieties, indicating that LuOH is assembled on the PySH-modified silver film. Furthermore, a band at 1221 cm−1 due to the in-plane C–H bending mode of PySH disappears, implying that the pyridyl moiety of PySH becomes more parallel to the silver surface upon the formation of the LuOH–PySH composite film. Additionally, an absorption band at 515 nm shifts to a longer wavelength (541 nm) and becomes broad upon the formation of the composite film, suggesting an interaction between LuOH and PySH in the film. By comparing the spectral changes between the two self-assembled composite films, we find that the central metal is crucial in the formation of the composite films. The structure and orientation of the composite films depend on the central metal of the metalloporphyrin compounds.
Development of Infrared Electroabsorption Spectroscopy and its Application to Molecular Structural Studies
Authors: Hiramatsu Hirotsugu , Hamaguchi Hiro-O
Published: April 2004

We have constructed an infrared electroabsorption spectroscopic system employing the alternating current (AC) coupled dispersive method developed previously in our laboratory. It is highly sensitive, measuring electric-field-induced infrared absorption changes as small as 6 × 10−8 in the mid-infrared region of 4000–820 cm−1. Infrared electroabsorption spectra of liquids and solutions can be measured at room temperature. The system was first applied to liquid acetone to observe the orientational as well as the electronic polarization signals. These signals show distinct behaviors that are exactly predicted by theory. It was then applied to liquid 1,2-dichloroethane, for which electric-field-induced gauche/trans equilibrium changes were detected as infrared absorption changes. The gauche/trans ratio in room-temperature liquid 1,2-dichloroethane has been determined for the first time as 1.4 ± 0.2. This equilibrium constant has led to the free energy difference Δ G of 0.9 ± 0.4 kJ mol−1 (Δ G = Gg – Gt) and the entropy difference of Δ S = 3.0 ± 1.4 J K−1 mol−1 with the known enthalpy difference Δ H; 0.0 kJ mol−1. Finally, the system was applied to 1,4-dioxane solutions of N-methylacetamide. The dipole moments of the monomer as well as that of the dimer of N-methylacetamide have been determined separately and a head-to-tail structure of the dimer has been clarified. The instrumentation and the theoretical basis of infrared electroabsorption spectroscopy are described in detail together with the above-mentioned experimental results.
Fourier Transform Raman Difference Spectroscopy for Detection of Lignin Oxidation Products in Thermomechanical Pulp
Authors: Vester Jette , Felby Claus , Nielsen Ole Faurskov , Barsberg Søren
Published: April 2004

Spruce thermomechanical pulp (TMP) was oxidized by the 2,29′-azinobis-3-ethylbenzthiazoline-6-sulfonate cation radical (ABTS•+) in the presence and absence of oxygen. The pulp modification was monitored by Fourier transform (FT) Raman difference spectroscopy and other nondestructive spectroscopic methods. The ABTS•+ oxidative system resulted in modifications very similar to the laccase–ABTS–oxygen system, except for the FT-Raman results, which showed a difference in mechanisms attributed to a difference in produced Raman bands. Oxygen resulted in no oxygen-derived products, but only enhanced the production of a specific Raman band of several oxidation-produced bands. Detailed information on lignin reactions can be obtained from FT-Raman signals.
THz Transmission Spectroscopy and Imaging: Application to the Energetic Materials PBX 9501 and PBX 9502
Authors: Funk David J. , Calgaro F. , Averitt R. D. , Asaki M. L. T. , Taylor A. J.
Published: April 2004

We report the measurement of the effective complex index of refraction near 1 THz for the Plastic-Bonded eXplosives PBX 9501 and PBX 9502. These plastic-bonded explosives consist of organic crystalline energetic materials, HMX and TATB, embedded in a binder matrix. We find that they are partially transparent at a few hundred GHz and we have applied a two-dimensional imaging technique for the detection of pre-fabricated defects in small samples.
Simulation of the Visible Spectra for Edible Virgin Olive Oils: Potential Uses
Authors: Ayuso Jesús , Haro María R. , Escolar Daniel
Published: April 2004

The photodegradation technique was used to record the visible spectra for carotenoids and chlorophylls in virgin olive oil. Principal component analysis of the visible spectra for 81 samples of this type of oil with widely variable composition revealed that only two components contribute more than 99.7% of the spectral information. The Varimax factors and the absorbances of the oil pigments are linearly related. The joint use of these spectra and the absorbances at 455 and 670 nm allows the accurate reproduction of the visible spectrum for any virgin olive oil sample. Therefore, one can question whether a commercially available product is actually virgin olive oil if a comparison of its experimental and simulated absorbance values gives R2 < 0.995 and RMSD > 0.006. The simulated spectra provide CIE L* a* b* chromatic coordinates that describe the color of the samples with little difference from those provided by the spectra for real samples.
Inferior Temporal, Prefrontal, and Hippocampal Contributions to Visual Working Memory Maintenance and Associative Memory Retrieval
Authors: Ranganath Charan , Cohen Michael X. , Dam Cathrine , D'Esposito Mark
Published: April 2004

Higher order cognition depends on the ability to recall information from memory and hold it in mind to guide future behavior. To specify the neural mechanisms underlying these processes, we used event-related functional magnetic resonance imaging to compare brain activity during the performance of a visual associative memory task and a visual working memory task. Activity within category-selective subregions of inferior temporal cortex reflected the type of information that was actively maintained during both the associative memory and working memory tasks. In addition, activity in the anterior prefrontal cortex and hippocampus was specifically enhanced during associative memory retrieval. These data are consistent with the view that the active maintenance of visual information is supported by activation of object representations in inferior temporal cortex, but that goal-directed associative memory retrieval additionally depends on top-down signals from the anterior prefrontal cortex and medial temporal lobes.
α‐Glucosidase Inhibitors
Authors: Rabasa‐Lhoret Rémi , Chiasson Jean‐Louis
Published: April 2004

α‐Glucosidase inhibitors produce a significant reduction of postprandial hyperglycemia and postprandial insulin with a significant decrease of HbA1c(∼0.7%), by delaying carbohydrate absorption. For diabetic patients, α‐glucosidase inhibitors are safe agents that can be used either as monotherapy or in combination with other oral hypoglycemic agents or insulin. The reduction of HbA1cshould substantially decrease microvascular complications and could diminish macrovascular events. α‐Glucosidase inhibitors should be considered as a treatment of choice for newly diagnosed diabetic patients. For those not well‐controlled with any other type of treatment, it can result in metabolic improvement without any additional risk. To minimize gastrointestinal side effects, treatment should be initiated at a low dose and titrated slowly. In patients with impaired glucose tolerance, acarbose has proven to be efficient in preventing or delaying the occurrence of type 2 diabetes as well as decreasing macrovascular events.
Combination Therapy in Type 2 Diabetes
Authors: Bajaj Mandeep , DeFronzo Ralph A.
Published: April 2004

Type 2 diabetes mellitus is a chronic metabolic disorder that results from defects in both insulin secretion and insulin action. Five classes of oral agents, each of which works through a different mechanism of action, are currently available to improve glycemic control in patients with type 2 diabetes mellitus. The United Kingdom Prospective Diabetes Study (UKPDS) has shown that type 2 diabetes mellitus is a progressive disorder that can be treated initially with oral agent monotherapy but will eventually require the addition of other oral agents, and that in many patients, insulin therapy will be needed to achieve targeted glycemic levels. This chapter examines the goals of antihyperglycemic therapy and reviews the mechanism of action, efficacy, nonglycemic benefits, and safety profile of each of the five approved classes of oral agents. A rationale for the use of these oral agents, as monotherapy, in combination with each other, and in combination with insulin, is provided.
Use of inventory and option contracts to hedge financial risk in planning under uncertainty
Authors: Barbaro Andres , Bagajewicz Miguel J.
Published: April 2004

The use of inventory and options in the management of financial risk in planning under uncertainty is analyzed. The intuitive notion that the addition of inventory can reduce risk is explored to reveal that it is only guaranteed if models managing risk are used and can otherwise lead to higher risk exposures. An example where risk is managed with options contracts is also presented, revealing that risk is also hedged only through an approach where risk is properly managed but not necessarily every time options are used. © 2004 American Institute of Chemical Engineers AIChE J, 50: 990–998, 2004
Autothermal reforming of gasoline using a cool flame vaporizer
Authors: da Silva J. Matos , Hermann I. , Mengel C. , Lucka K. , Köhne H.
Published: April 2004

The phenomenon of cool flames can be used for mixing, evaporation, and overheating of a mixture of fuel, air, and steam. This method is used to provide a homogeneous mixture preparation. This study investigates the existence of cool flames running a stationary cool flame reactor under autothermal reforming conditions. It particularly characterizes the thermal limits of the cool flame reaction at high steam‐to‐carbon ratios. The experiments show that a cool flame vaporizer can be combined with an autothermal reformer leading to a homogeneous temperature profile in the front of the catalyst bed. This results in a good conversion of the fuel in the reforming process. 2004 American Institute of Chemical Engineers AIChE J, 50: 1042–1050, 2004)
Adsorption properties of polyacrylonitrile‐based activated carbon hollow fiber
Authors: Sun Junfen , Wu Guangxiang , Wang Qingrui
Published: April 2004

In this work, polyacrylonitrile (PAN) hollow fibers are pretreated with ammonium dibasic phosphate and then further oxidized in air, carbonized in nitrogen, and activated with carbon dioxide. The adsorption properties of the resultant activated carbon hollow fibers (ACHF) prepared in different conditions were studied. The results show that the adsorption properties of ACHF change regularly with preparing conditions of ACHF. The different adsorption ratios to three adsorbates reflect the number of micropores and mesopores in PAN‐based ACHF. Pretreatment with phosphate can increase the number of mesopores. Proper oxidation temperature and time can increase the number of micropores and mesopores. When carbonization temperature is more than 900°C and carbonization time ranges from 50 to 90 min, the number of micropores and mesopores, especially mesopores, greatly increases. Compared with other treatments, activation treatment greatly increases the number of micropores and mesopores, and the dominant pore sizes of mesopores in PAN‐based ACHF are from 2 to 10 nm. © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 93: 602–607, 2004
Group 1 Coordination Chains and Hexagonal Networks of Host Cyclotriveratrylene with Halogenated Monocarbaborane Anions
Authors: Ahmad Ruksanna , Franken Andreas , Kennedy John D. , Hardie Michaele J.
Published: April 2004

Halogenated carbaborane ions [CB11H6X6]− in which X=Cl or Br have been combined with the host molecule cyclotriveratrylene (CTV) and Group 1 metal cations to give crystalline materials. The complexes [Na(ctv)(H2O)(CB11H6X6)](CF3CH2OH) feature chiral Na–CTV coordination chains with complexation of the [CB11H6X6]− ion by the Na+ ion, together with the CTV molecular cavity. The coordination chains are hydrogen bonded together to give a puckered two‐dimensional hexagonal grid structure. [K(ctv)(CB11H6Cl6)(CF3CH2OH)0.5] is essentially isostructural. Complexes [Rb(ctv)(CB11H6Br6)(H2O)] and [Cs(ctv)(CB11H6X6)(CH3CN)] are coordination polymers with related distorted hexagonal grid structures. Use of N,N′‐dimethylformamide (DMF) as a solvent results in an entirely different type of assembly, with [Na2(dmf)4(H2O)2(ctv)][(dmf)0.5(ctv)][CB11H6Br6]2 showing unusual {Na‐μ‐(dmf)‐Na} bridges, and once again forming a distorted hexagonal coordination polymer.
Total Synthesis of Macroviracin D (BA‐2836‐4)
Authors: Mlynarski Jacek , Ruiz‐Caro Juliana , Fürstner Alois
Published: April 2004

The first total synthesis of the complex glycolipid macroviracin D (BA‐2836‐4) (1) is described. This antivirally active metabolite isolated from the mycelium extracts of Streptomyces sp. BA‐2836 incorporates a unique 46‐membered macrodilactone motif decorated with glycosylated fatty acid appendices. Compound 1 consists of three identical subunits which are closely related to one of the segments found in cycloviracin B1 (2), another antiviral glycoconjugate previously synthesized in our laboratory. Key steps of the synthesis route to 1 involve the stereoselective, ligand‐controlled addition of the functionalized diorganozinc derivative 9 to aldehydes 8 a, b, a series of β‐selective glycosidation reactions using appropriately protected trichloroacetimidate donors, and three esterifications via the Yamaguchi method; one of them is performed intramolecularly to forge the macrocyclic lactone ring of the target in 89 % isolated yield. This total synthesis also firmly establishes the absolute configuration of the subunits of compound 1 as 3R,17S,23R.
Enantioselective [4+2]‐Cycloaddition Reaction of a Photochemically Generated o‐Quinodimethane: Mechanistic Details, Association Studies, and Pressure Effects
Authors: Grosch Benjamin , Orlebar Caroline N. , Herdtweck Eberhardt , Kaneda Masayuki , Wada Takehiko , Inoue Yoshihisa , Bach Thorsten
Published: April 2004

1,2,3,4‐Tetrahydro‐2‐oxoquinoline‐5‐aldehyde (2) was prepared from m‐aminobenzoic acid and 3‐ethoxyacryloyl chloride (4) in 19 % overall yield. Compound 2 underwent a photochemically induced [4+2]‐cycloaddition reaction with various dienophiles upon irradiation in toluene solution. The exo product 10 a was obtained with acrylonitrile (9 a) as the dienophile, whereas methyl acrylate (9 b) and dimethyl fumarate (9 c) furnished the endo products 11 b and 11 c (69–77 % yield). The reactions proceeded at −60 °C in the presence of the chiral complexing agent 1 (1.2 equiv) with excellent enantioselectivity (91–94 % ee). The enantiomeric excess increases in the course of the photocycloaddition as a result of the lower product association to 1. The intermediate (E)‐dienol 8 was spectroscopically detected at −196 °C in an EPA (diethyl ether/isopentane/ethanol) glass matrix. The association of the substrate 2 to the complexing agent 1 was studied by circular dichroism (CD) titration. The measured association constant (KA) was 589 M−1 at room temperature (25 °C) and normal pressure (0.1 MPa). An increase in pressure led to an increased association. At 400 MPa the measured value of KA was 703 M−1. Despite the stronger association the enantioselectivity of the reaction decreased with increasing pressure. At 25 °C the enantiomeric excess for the enantioselective reaction 2 + 9 a→10 a decreased from 68 % ee at 0.1 MPa to 58 % ee at 350 MPa. This surprising behavior is explained by different activation volumes for the diastereomeric transition states leading to 10 a and ent‐10 a.
Highly Enantioselective Ruthenium‐Catalyzed Reduction of Ketones Employing Readily Available Peptide Ligands.
Authors: Boegevig Anders , Pastor Isidro M. , Adolfsson Hans
Published: April 2004

For Abstract see ChemInform Abstract in Full Text.
One‐Pot Synthesis of N‐Acyl‐Substituted Sulfamides from Chlorosulfonyl Isocyanate via the Burgess‐Type Intermediates.
Authors: Masui Yoshiyuki , Watanabe Hideaki , Masui Toshiaki
Published: April 2004

For Abstract see ChemInform Abstract in Full Text.
From Allylic Alcohols to Aldols via a Novel, Efficient Reaction Catalyzed by Ni‐Complexes.
Authors: Cuperly David , Crevisy Christophe , Gree Rene
Published: April 2004

For Abstract see ChemInform Abstract in Full Text.
Palladium‐Catalyzed Aryl‐Amidation. Synthesis of Non‐Racemic N‐Aryl Lactams.
Authors: Browning R. Greg , Badarinarayana Vivek , Mahmud Hossen , Lovely Carl J.
Published: April 2004

For Abstract see ChemInform Abstract in Full Text.
Synthesis of Some Trifluoromethyl Substituted 1‐Methylpyrazoles.
Authors: Pavlik James W. , Ayudhya Theppawut Israsena Na , Tantayanon Supawan
Published: April 2004

For Abstract see ChemInform Abstract in Full Text.
Versatile 2‐Aminothiazoles, Building Blocks for Highly Functionalized Heterocycles.
Authors: Kaupp Gerd , Amer Fathy A. , Metwally Mohamed Abbas , Abdel‐latif Ehab
Published: April 2004

For Abstract see ChemInform Abstract in Full Text.
A Unified Approach to the Enantioselective Synthesis of 2,6‐cis and trans Disubstituted Tetrahydropyranones.
Authors: Crimmins Michael T. , Diaz Caroline J. , Emmitte Kyle A.
Published: April 2004

For Abstract see ChemInform Abstract in Full Text.
α‐Trifluoroacetyl‐δ‐valerolactone: Synthesis, Acyl‐lactone Rearrangement and Unexpected Easy Decarboxylation of the Rearranged Product.
Authors: Sevenard Dmitri V. , Lork Enno
Published: April 2004

For Abstract see ChemInform Abstract in Full Text.
Stereoselective Total Synthesis of the Nonenolide (+)‐Microcarpalide
Authors: Banwell Martin G. , Loong David T. J.
Published: April 2004

For Abstract see ChemInform Abstract in Full Text.
Hydrothermal Synthesis of Prismatic NaHoF4 Microtubes and NaSmF4 Nanotubes.
Authors: Liang Lifang , Xu Huifang , Su Qiang , Konishi Hiromi , Jiang Yingbin , Wu Mingmei , Wang Yifeng , Xia Deying
Published: April 2004

For Abstract see ChemInform Abstract in Full Text.
Group 15 Element Imido and Phosphido Cages: Coordination Chemistry and Synthetic Applications
Authors: Doyle Emma L. , Hopkins Alexander D. , Lawson Gavin T. , McPartlin Mary , Woods Anthony D. , Wright Dominic S.
Published: April 2004

For Abstract see ChemInform Abstract in Full Text.
The European Commission Perspective in Biomass and Waste Thermochemical Conversion
Authors: Maniatis K. , Guiu G. , Riesgo J.
Published: April 2004

For Abstract see ChemInform Abstract in Full Text.
Azido Polymers‐Energetic Binders for Solid Rocket Propellants
Authors: Gaur Bharti , Lochab Bimlesh , Choudhary V. , Varma I. K.
Published: April 2004

For Abstract see ChemInform Abstract in Full Text.
Challenges in Oxidation Catalysis
Authors: Buijs W.
Published: April 2004

For Abstract see ChemInform Abstract in Full Text.
Fluorous Mixture Syntheses (FMS)
Authors: Zhang Wei
Published: April 2004

For Abstract see ChemInform Abstract in Full Text.
Paramagnetic Cp/Dithiolene Complexes as Molecular Hinges: Interplay of Metal/Ligand Electronic Delocalization and Solid‐State Magnetic Behavior
Authors: Fourmigue Marc
Published: April 2004

For Abstract see ChemInform Abstract in Full Text.
Fine‐needle aspiration cytology of pseudoangiomatous stromal hyperplasia of the breast
Authors: Lui Philip C.W. , Law Bonita K.B. , Chu Winnie C.W. , Pang Lai‐Man , Tse Gary M.K.
Published: April 2004

Pseudoangiomatous stromal hyperplasia (PASH) is an uncommon lesion usually found in premenopausal women. Histologically, it is characterized by complex, anatomosing, empty slit‐like spaces in a dense collagenous stroma. These pseudoangiomatous spaces are lined by monomorphic spindle cells of myofibroblastic differentiation. Cytological features of PASH are rarely discussed and reported, and may pose diagnostic challenge to surgical pathologists. Two cases of PASH are reported with emphasis on the FNAC features and cytologic differentiation from other benign fibroepithelial lesions. Diagn. Cytopathol. 2004;30:353–355. © 2004 Wiley‐Liss, Inc.
Optical property of electro‐tunable defect mode in 1D periodic structure with light crystal defect layer
Authors: Ozaki Ryotaro , Matsui Tatsunosuke , Ozaki Masanori , Yoshino Katsumi
Published: April 2004

A liquid crystal defect layer is introduced into a one‐dimensional photonic crystal and its optical distance is varied by an electric field so that the defect mode can be controlled. An optical propagation simulation is carried out for study of optical characteristics in a model in which nematic liquid crystal is introduced as a liquid crystal defect layer in a dielectric multilayer as a one‐dimensional photonic crystal. We investigate whether the defect mode can be controlled by varying the optical length by way of change in orientation of the liquid crystal molecules. Based on the simulation results, a device is fabricated with a nematic defect layer introduced within a SiO2/TiO2 laminated periodic structure. The defect mode of the one‐dimensional photonic crystal is measured. It is confirmed that the experimental results and the simulation results agree well. Further, it is successful in shifting the defect mode wavelength by applying a voltage. Hence, it is clear that the defect mode can be modulated by changing the optical length of the defect layer by means of control of the orientation of the liquid crystal molecules by an applied voltage. © 2004 Wiley Periodicals, Inc. Electron Comm Jpn Pt 2, 87(5): 24–31, 2004; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/ecjb.10167
Asymptotic analyses of diffracted field by an aperture in a conducting screen
Authors: Kawano Toru , Ishihara Toyohiko , Murohara Eiji
Published: April 2004

In this paper, the integral expressing the field diffracted by an aperture sufficiently larger than the wavelength created in a conducting screen is derived by the aperture field method. By evaluating the integral asymptotically, the extended Fraunhofer approximation and a uniform asymptotic solution for the aperture field methods are derived. By comparison with the reference solution derived by direct numerical integration, the usefulness, applicable range, and physical interpretation of the asymptotic solution are investigated. A new criterion is derived for adopting a nonuniform asymptotic solution applicable outside the transition region and the conventional Fraunhofer approximation from the uniform asymptotic solution. The validity of this technique is demonstrated numerically. The effectiveness of the technique is clarified by comparing a reference solution obtained by the method of moments and uniform asymptotic solutions obtained by the three types of aperture field methods. © 2004 Wiley Periodicals, Inc. Electron Comm Jpn Pt 2, 87(5): 1–12, 2004; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/ecjb.10203
Structural pattern recognition of biological textures with growing deformations: A case of cattle's muzzle patterns
Authors: Kimura Akio , Itaya Kazushi , Watanabe Takashi
Published: April 2004

Textured patterns on living organisms (hereafter referred to as biological textures), which are typified by human fingerprints or cattle muzzle patterns, have features that differ according to the individual organism, and it is well known that these biological textures can be used for identification. However, the pattern structure of cattle muzzle patterns, for example, is more complex than that of human fingerprints, and since the structure features are changed or deformed during the growing stage, these pattern structures cannot be skillfully recognized by using a technique like the one used for conventional fingerprint comparison. In this paper, the authors propose a new recognition technique that is applicable even to biological textures with these kinds of growing deformations. Specifically, they focus on cattle muzzle patterns as an example of a biological texture and select graph matching based on a horizontal search as the basic strategy to create this new recognition technique consisting of a technique for determining a pair of Hough‐transformed search‐starting cycles and a muzzle pattern recognition method that improves search efficiency by incorporating processing for merging non‐searched cycles. The authors performed evaluation experiments to verify the effectiveness of the proposed technique and obtained good results. © 2004 Wiley Periodicals, Inc. Electron Comm Jpn Pt 2, 87(5): 54–66, 2004; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/ecjb.20076
Sexually dimorphic basal water absorption at the isolated pelvic patch of Japanese tree frog, Hyla japonica
Authors: Kohno Satomi , Fujime Makoto , Kamishima Yoshihisa , Iguchi Taisen
Published: April 2004

Frogs ingest little water orally, but absorb the majority of the water needed for normal physiological performance through a specific region of the ventral skin, the pelvic patch. We observed non‐stimulated (basal water absorption, BWA) water flux through the isolated pelvic patch in vitro in Japanese tree frog (Hyla japonica). We found that water flux through non‐stimulated skin from the pelvic patch was greater in males than females. This water flux was confirmed as BWA by observing no effect following the in vitro administration of propranolol and [adamantaneacetyl1, O‐Et‐D‐Tyr2, Val1, aminobutyryl6, Arg8, 9] vasopressin, which are a β‐adrenergic receptor antagonist and a vasopressin V2 receptor antagonist, respectively. We further examined this phenomenon following gonadectomy, treatment with sex hormones (E2, 17β‐estradiol; TP, testosterone propionate), estrogenic chemicals (BPA, bisphenol A; MTX, methoxychlor) or prolactin (PRL, a hormone regulated by sex hormones that has osmoregulatory activity). Ovariectomy increased BWA in females. Injection (in vivo treatment) of E2 or PRL reduced BWA in males, whereas TP injection increased BWA in females. However, the in vitro addition of E2, TP, or PRL to the Ringer's solution on the serosal side of the ventral skin patch did not alter BWA. Subsequently, we injected (in vivo treatment) BPA or MTX, environmental chemical contaminants with known hormonal actions in mammals. Injection of BPA or MTX reduced BWA in males as observed following treatment with E2. These results provide the first evidence of sexual dimorphism in BWA through the isolated pelvic patch. The gonad appears essential for observed sexual dimorphism in BWA, and we hypothesize that sex hormones regulate the release of PRL, that in turn influences BWA indirectly. E2 is known to exert a specific stimulatory effect on PRL secretion. In addition, we have observed that some endocrine disrupting contaminants also eliminate the sexual dimorphism in BWA observed in the Japanese tree frog. J. Exp. Zool. 301A:428–438, 2004. © 2004 Wiley‐Liss, Inc.
Soft tissue enhancement on time‐resolved peripheral magnetic resonance angiography
Authors: Zhang Hong Lei , Kent K. Craig , Bush Harry L. , Winchester Priscilla A. , Watts Richard , Wang Yi , Prince Martin R.
Published: April 2004

Purpose

To evaluate the incidence and locations of soft tissue enhancement on time‐resolved two‐dimensional projection magnetic resonance angiography (MRA) of the calf and foot.

Materials and Methods

Time‐resolved two‐dimensional projection MRA of the knee, calf, and foot, performed at 1.5 Tesla using the head coil, was retrospectively reviewed in 326 patients. Soft tissue enhancement of the foot was identified and graded by blinded review. Subsequently, patient medical records were reviewed to determine the presence or absence of diabetes, cellulitis, gangrene, and ulceration of the foot and presence of neuropathic joints.

Results

Enhancing spots were identified in 228 patients. For those feet without clinical abnormalities, diabetic patients had an average of 1.2 enhancing spots per foot, while nondiabetics had only 0.6 (P < 0.001). Higher‐grade lesions were more prevalent in diabetics and in heavier patients. Of 64 patients with follow‐up, 8 (13%) developed cellulitis (N = 4) or ulceration (N = 4) at the location of an enhancing spot, including 5 diabetic and 3 nondiabetic patients.

Conclusion

Pedal soft tissue enhancement frequently occurs on time‐resolved gadolinium (Gd):MRA of the feet. The etiology is uncertain, but the high frequency in diabetic patients and observation of progression to cellulitis/ulceration suggest this soft tissue enhancement may identify sites of subclinical pedal soft tissue injury. J. Magn. Reson. Imaging 2004;19:590–597. © 2004 Wiley‐Liss, Inc.
Emotional intelligence in leaders: an antidote for cynicism towards change?
Authors: Ferres Natalie , Connell Julia
Published: April 2004

Business leaders everywhere have encountered the reality of resistance and cynicism when introducing change initiatives.

This paper identifies some of the associations between the challenges of organizational change in the 21st century and the emotional competencies required of contemporary change leaders.

The aim of this paper is to explore the impact of leader emotional intelligence (EI) on levels of employee cynicism towards change.

Results from a survey of 448 employees supported the hypothesis that employees would report less change cynicism if managed by leaders whom subordinates rated as emotionally intelligent.

This study will be of interest to managers and people concerned with leadership, change management, emotional intelligence and securing a competitive advantage.

Copyright © 2004 John Wiley & Sons, Ltd.
Primary retroperitoneal teratomas: A review of the literature
Authors: Gatcombe Heather G. , Assikis Vasily , Kooby David , Johnstone Peter A.S.
Published: April 2004

Teratomas are uncommon neoplasms comprised of mixed dermal elements derived from the three germ cell layers. Historically, teratomas were attributed to demons, sexual misconduct, and abnormal fertilization. They attract attention because of their bizarre histology and gross appearance. While the majority of teratomas present congenitally in the sacrococcygeal region, within the ovaries of adolescent females and within the testes of young men, they have been identified throughout the body. Extragonadal teratomas tend to occur in midline structures as the anterior mediastinum, retroperitoneum, sacrococcygeal region, and pineal gland. Retroperitoneal teratomas represent only 1–11% of primary retroperitoneal tumors. Incidence is bimodal with peaks in the first 6 months of life and in early adulthood. Due to their location, they are usually identified only after they have grown to huge proportions. There is a 25% chance of malignancy. Surgical resection remains the mainstay of therapy and is required for definitive diagnosis. This article reviews the literature on the histopathology, classification, genetic abnormalities, and theories of origin of teratomas as well as the presentation, diagnosis, and management of retroperitoneal teratomas. J. Surg. Oncol. 2004;86:107–113. © 2004 Wiley‐Liss, Inc.
1. History of CA and evolution of the markets
Authors: Rustemeyer Paul
Published: April 2004

An overlook is given of the 100 years of technical, industrial and chemical development of cellulose acetate. CA has been used as raw material in the fields of laquer, plastics, textile, Filter Tow, film, membrane and others. In the field of applications for plastics and textiles CA was quite successful for many years, but was then slowly substituted by other polymers. Total cellulose acetate demand is growing, especially for Filter Tow in cigarettes filters and film for polarisers in LCD‐displays.
4. Characteristics of cellulose acetates 4.1 Characterization and physical properties of cellulose acetates
Authors: Zugenmaier Peter
Published: April 2004

An overview is provided of the basic features of cellulose acetate of various degree of substitution in the solid and liquid crystalline state as well as in solution. These features represent a necessity for an understanding of the properties of these cellulose derivatives and further for mixed esters, which are not presented in this paper. Specifically, the crystal structure of cellulose triacetate will be addressed as well as structures in dilute and semi‐dilute solutions. Thermal, viscoelastic and further properties in the solid state are discussed as well as flow behavior of solutions and their application in molecular weight determination, including false viscosity of commercial 2.5 cellulose acetates.
Role of basic helix‐loop‐helix (bHLH) and CREB transcription factors in the regulation of sertoli cell androgen‐binding protein expression
Authors: Saxlund Melissa A. , Sadler‐Riggleman Ingrid , Skinner Michael K.
Published: April 2004

Differentiation of Sertoli cells is marked by the presence of novel gene products such as transferrin and androgen‐binding protein (ABP). Transcriptional regulation of Sertoli cell differentiation is, in part, controlled through the binding of specific transcription factors to response elements within these genes promoters. Transferrin gene expression has been shown to be regulated by the binding and interactions of basic helix‐loop‐helix (bHLH) and cAMP response element binding protein (CREB) to an E‐box and cyclic AMP response element (CRE), respectively. Interaction between the bHLH and CREB is facilitated through subsequent binding of CREB‐binding protein (CBP)/p300. The hypothesis tested in the current study is that ABP expression is regulated by a similar mechanism. The ABP promoter activation was analyzed through the use of transfection assays, site‐directed mutagenesis, and electromobility shift assays (EMSA). Transient transfections of rat Sertoli cells used a reporter construct containing the proximal 619 bp of the ABP promoter. Observations suggest that cAMP and follicle stimulating hormone (FSH) upregulate the expression of ABP. Mutational studies of the three E‐boxes and the CRE of the 619‐bp ABP promoter indicate that all of these elements are critical for stimulation of promoter activity. EMSA revealed a weak interaction between an E‐box‐2 and the CRE that are overlapping in the promoter. An artificial promoter that contains only an E‐box and CRE was created to further test this hypothesis. The artificial promoter was stimulated by both FSH and cAMP. Experiments with mutants of the artificial promoter demonstrate that both response elements contribute to the optimal activation of the promoter construct. The overexpression of the bHLH inhibitor Id (i.e., inhibitor of differentiation) that binds bHLH proteins and eliminates DNA binding was found to suppress hormone activation of the ABP promoter. Combined observations of the ABP promoter and artificial promoter provide insight into a common mechanism for gene regulation in differentiated Sertoli cells involving a role for both the bHLH and CREB family of transcription factors. Mol. Reprod. Dev. 68: 269–278, 2004. © 2004 Wiley‐Liss, Inc.