bluuebunny/crossref_metadata_2025 huggingface dataset:
Aromatic Sulfonation, 131. Formation of Sulfonic Acids and Sulfonic Anhydrides in the Sulfur Trioxide Sulfonation of Some Dialkylbenzenes and 1,ω‐Diarylalkanes
Authors: Cerfontain Hans , Koeberg‐Telder Ankie , van Lindert Helen C. A. , Bakker Bert H.
Published: July 2007

An exploratory study has been made on the SO3 sulfonation of a number of alkylarenes in [D2]dichloromethane as an aprotic solvent, mostly in the presence of [D8]1,4‐dioxane as a reactivity moderator, in order to obtain information on sulfonic acid and sulfonic anhydride formation. 1,2‐Dimethylbenzene (1) with 1.0 mol‐equiv. of SO3 yields predominantly the 4‐sulfonic acid (1‐4‐S), whereas with 4.0 mol‐equiv. of SO3, 18 mol‐% of the corresponding (intermolecular) sulfonic anhydride (1‐4‐SO2)2O is additionally formed. 1,4‐Dimethylbenzene (2) with 0.8 mol‐equiv. of SO3 yields predominantly 2‐2‐S, whereas with 4.0 mol‐equiv. of SO3 the sulfonic anhydride (2‐2‐SO2)2O and its 6‐S and 6,6′‐S2 derivatives are formed, the eventual main product being (6‐S‐2‐2‐SO2)2O. Reaction of 1‐ethyl‐4‐methylbenzene (3) with 2.0 mol‐equiv. of SO3‐[D8]dioxane at −78 → −40 °C leads to the predominant formation of the 2‐ and 3‐S derivatives in a molar ratio of 26:74, with small amounts of the three corresponding intermolecular anhydrides. Upon performing the sulfonation of 3 at 0 → 22 °C, the relative amounts of the anhydrides are larger, and in addition the 3,5‐S2 derivatives of the intermolecular anhydrides are formed. The absence of the isomeric 2,6‐S2 derivative is ascribed to the buttressing effect of the 2‐sulfo on the 1‐ethyl group, hampering the sulfonation at C(6). Reaction of diphenylmethane (4) with 4.2 mol‐equiv. of SO3 at −20 → 25 °C yields initially 4‐4′‐S and subsequently 4‐4′,4″‐S2. Sulfonation of 1,2‐diphenylethane (5) with 4.0 mol‐equiv. of SO3 at −78 → 22 °C for 4.5 h leads mainly to the cyclic dimeric disulfonic anhydride [5‐4′,4″(‐SO2)2O]2, which upon hydrolysis affords 9% of 5‐2′,4″‐ and 91% of 5‐4′,4″‐S2. However, sulfonation of 5 at 0 → 22 °C for ca. 0.8 h was found to lead to the formation of the intermolecular sulfonic anhydride (4′‐S‐5‐4″‐SO2)2O. On sulfonation of 1,2‐di‐p‐tolylethane (6) with 1.0 mol‐equiv. of SO3, only ca. 20% of the substrate was sulfonated to give, after hydrolysis, 3% of the 2′‐ and 12% of the 3′‐sulfonate, whereas with 4.0 mol‐equiv. of SO3 the initial monosulfonic acids are almost completely converted to yield the 2′,3″,5″‐S3, 3′,3″,5″‐S3, and 3′,3″,5′,5″‐S4.
A Short Synthesis of (±)‐Oxetin
Authors: Bach Thorsten , Schröder Jürgen
Published: July 2007

The antibiotic β‐amino acid oxetin (rac‐1) has been prepared by the stereoselective Paternò‐Büchi reaction of enecarbamate 2 and n‐butyl glyoxylate (5). The overall yield of the four‐step synthesis is 14%. The order of the deprotection steps proved to be important in minimizing possible side reactions.
Dihydrocolchicine 8,12‐Endoperoxide: A Novel Starting Material for Convenient Syntheses of the Allocolchicinoids N‐Acetylcolchinol O‐Methyl Ether and Androbiphenyline
Authors: Brecht René , Haenel Frank , Seitz Gunther
Published: July 2007

Optically pure dihydrocolchicine‐8,12‐endoperoxide 2 is used as the starting material for the synthesis of some bioactive allocolchicinoids. Depending on the reaction conditions and reagents employed, different modifications of the C ring of colchicine (1) are achieved. Triphenylphosphane deoxygenation of 2 leads to the well known N‐acetylcolchinol O‐methyl ether (NCME, 6, 40% yield from 1). Treatment of the endoperoxide 2 with CH3OH/CH2Cl2/silica gel provides the plant alkaloid androbiphenyline (11) in a yield of 60% from 1. Triethylamine‐catalysed transformation of 2 yields (−)‐colchicine‐8,12‐dione (12) (17% yield), together with a mixture of interconverting tetracyclic hemiketals 8a and 8b. For the formation of the allo colchicinoids 6 and 11 plausible reaction pathways are suggested. In contrast to what is found in the literature, the assignment of the absolute configuration of natural (−)‐colchicine (1), and the allo‐congeners 6 and 11, should be (M,7S) or (aR,7S) instead of (aS,7S).
Efficient In‐Situ Redox Catalytic NAD(P)+ Regeneration in Enzymatic Synthesis Using Transition‐Metal Complexes of 1,10‐Phenanthroline‐5,6‐dione and Its N‐Monomethylated Derivative as Catalysts
Authors: Hilt Gerhard , Lewall Burhanshah , Montero Guillermo , Utley James H. P. , Steckhan Eberhard
Published: July 2007

In comparative studies, we have been able to demonstrate that redox catalysts based on transition‐metal complexes using 1,10‐phenanthroline‐5,6‐dione as a ligand or based on N‐methylated 1,10‐phenathroline‐5,6‐dione acting via hydride ion abstraction are superior to alternative methods for the redox catalytic aerobic or indirect electrochemical in situ NAD(P)+ regeneration in enzymatic syntheses using alcohol dehydrogenases as production enzymes. Under preparative conditions in the gram scale we were able to obtain turnover frequencies of up to 130 turnovers per hour with respect to the redox catalyst. These are far larger than those of the presently most popular regeneration system.
Lactones, 2. Synthesis of Enantiomeric Pairs of Lactones with the Pinane or the Fenchane system
Authors: Paruch Edyta , Ciunik Zbigniew , Wawrzeńczyk Czeslaw
Published: July 2007

Starting from (+)‐ and (−)‐myrtenols, and via iodolactonization, the enantiomerically pure tricyclic lactones, with pinane systems, were obtained. In the course of an acidic lactonization of the γ,δ‐epoxy esters 6a and 6b, the rearrangement of the pinane system to that of the fenchane was observed. The absolute configurations of the newly formed chiral centres of the lactones 4b and 11b were established by X‐Ray diffraction analyses.
Biotransformation of Ergot Alkaloids by Haloperoxidase from Streptomyces aureofaciens: Stereoselective Acetoxylation and Propionoxylation
Authors: Křen Vladimír , Kawuloková Libuše , Sedmera Petr , Polášek Miroslav , Lindhorst Thisbe K. , van Pée Karl‐Heinz
Published: July 2007

Agroclavine (1) was oxidized, by haloperoxidase from Streptomyces aureofaciens, to 2,3‐dihydro‐6,8‐dimethyl‐3β‐acetoxy‐8‐ergolen‐2‐one (2) in the presence of sodium acetate and bromine ions. Acetate was incorporated into the above product during oxidation. In a propionate buffer, incorporation of propionate into the product was observed, yielding 2,3‐dihydro‐6,8‐dimethyl‐3β‐propionoxy‐8‐ergolen‐2‐one (4). The biotransformation proceeded faster in the propionate buffer, affording also the higher oxidation product (4aS),(10bS)‐7‐amino‐3,4,4a,5,6,10b‐hexahydro‐2,4‐dimethyl‐6‐oxobenzo[f]quinoline (3).
Addition and Cyclization Reactions in the Thermal Conversion of Hydrocarbons with an Enyne Structure, 5. High‐Temperature Ring Closures of 1,3‐Hexadien‐5‐ynes to Naphthalenes – Competing Reactions via Isoaromatics, Alkenylidene Carbenes, and Vinyl‐type Radicals
Authors: Hofmann Jörg , Schulz Kathrin , Altmann Annett , Findeisen Matthias , Zimmermann Gerhard
Published: July 2007

The 4‐substituted 1‐phenyl‐1‐butene‐3‐ynes 1a–c and the 2‐ethynylstyrenes 7a–c were subjected to high‐temperature pyrolysis. The cycloisomerization products isolated suggest that these are formed by three competing processes: by (i) an electrocyclic or a molecule‐induced, (ii) an alkenylidene carbene controlled, and (iii) a radical‐controlled ring‐closure process. To estimate the relative importance of these three reactions here mentioned, the substrates have been isomerized in oxygen‐free nitrogen and in nitrogen proportionally substituted by toluene at 700 and 650 °C, respectively. The relative contributions of these isomerizations depend not only on the conversion temperature but also on the substitutent R in 1 or 7.
Assessment of myocardial oxygen extraction fraction and perfusion reserve with BOLD imaging in a canine model with coronary artery stenosis
Authors: Zhang Haosen , Gropler Robert J. , Li Debiao , Zheng Jie
Published: July 2007

Purpose

To determine the feasibility of T2‐weighted BOLD imaging for estimating regional myocardial oxygen extraction fraction (OEF) and approximating perfusion reserve (MPR) simultaneously in a canine model with moderate coronary artery stenosis.

Materials and Methods

Eight mongrel dogs with moderate coronary artery stenosis underwent BOLD imaging at rest and during dipyridamole‐induced hyperemia, using a turbo spin echo (TSE) sequence. Based on a two‐compartment model, myocardial OEFhyperemia was calculated with the corresponding T2. MPR could be approximated based on Fick's law.

Results

During responsive hyperemia, a regional hypointensity was observed in the abnormally perfused myocardium, reflecting a relatively smaller myocardial T2 increase (3.06% ± 2.74%, in contrast to 10.19% ± 4.12% in the normal region). The average OEFs in the normally and abnormally perfused myocardial territories were 0.21 ± 0.11 and 0.43 ± 0.12, respectively. For the MPR approximated from the BOLD imaging, a strong correlation (R = 0.9) in the normal myocardium and a good correlation (R = 0.6) distal to the stenosis were obtained compared to microsphere results.

Conclusion

In a canine model with moderate coronary artery stenosis, TSE‐based BOLD imaging can quantitatively estimate the regional OEFhyperemia and approximate the MPR, and can distinguish segments perfused by defected coronary artery. J. Magn. Reson. Imaging 2007;26:72–79. © 2007 Wiley‐Liss, Inc.
Phosphorus indices as risk‐assessment tools in the U.S.A. and Europe—a review
Authors: Buczko Uwe , Kuchenbuch Rolf O.
Published: July 2007

The “phosphorus index” (PI) is a semiquantitative tool to assess the risk of P loss from fields to surface waters, which is based on simple arithmetic computations of source (soil test phosphorus (STP), P applications as manure and fertilizer, plant residues) and transport factors (erosion, surface runoff, subsurface drainage, connectivity). Work done since the 1990s in the U.S.A. and several European countries has shown that this approach is capable of delineating critical source areas for P export within a watershed. It is intended to adopt such a PI tool in Germany as well. However, there is no “standard” PI, and the variety of P indices is confusing, since each state and country has developed its own version to account for special regional conditions which are important for P loss. This paper reviews the factors of P loss which are taken into account in P indices and different modifications of P indices according to their components and structural approach. The literature concerning single source and transport factors of P loss is overwhelming, and a structured selection is given in this review.

Most P indices can be classed into one of three groups: 1. additive approach, 2. multiplicative approach, and 3. multiplicative‐additive approach.

For Germany, it is suggested that specific factors of P loss are incorporated into the basic backbone of a Pennsylvania‐style PI. Realization of the factors could be adopted from existing Scandinavian P indices or from other research results.
Presence of indigestible peptide aggregates of soybean meal in pig ileal digesta residue
Authors: Fischer Morten , Voragen Alphons GJ , Piersma Sander R , Kofod Lene V , Joergensen Christian I , Guggenbuhl Patrick , Nunes Carlos S , Gruppen Harry
Published: July 2007

With the purpose of analysing the molecular size and composition, proteinaceous material was extracted from the insoluble components of a digesta sample obtained from pigs fed a feed consisting of only soybean meal. Gel permeation chromatography indicated that the alkali‐extractable fraction of the proteinaceous material from the residue was of relatively high apparent molecular weight. However, the combined results from gel electrophoresis, RPLC‐MS, and MALDI‐ToF MS showed that the extracted protein material was in fact, to a high extent, composed of aggregated peptides. To our knowledge this has not previously been described. Aggregates extracted by dilute alkali were fully degraded upon subsequent proteolytic treatment. N‐terminal sequencing of selected protein bands from SDS‐PAGE gels indicated the presence of partly degraded β‐conglycinin alpha subunits in the residue. Copyright © 2007 Society of Chemical Industry
Heat shock proteins 47 and 70 expression in rodent skin model as a function of contact cooling temperature: Are we overcooling our target?
Authors: Brown Spencer A. , Farkas Jordan P. , Arnold Christopher , Hatef Daniel A. , Kim Jane , Hoopman John , Kenkel Jeffrey M.
Published: July 2007

Background and Objectives

The degree of protective cooling required during laser therapy to achieve an optimal result is unknown. The expression of heat shock proteins, Hsp47 and Hsp70, were examined in the epidermis and dermis as biomarkers to quantify the degree and depth of tissue affected by non‐ablative laser treatment using variable protective cooling parameters.

Study Design/Materials and Methods

Twenty‐one male Sprague–Dawley rats were treated with a 1,319 nm Nd:YAG laser using a sapphire cooling plate attached to the hand piece. A 4 cm×4 cm area on each side of the rat was treated with the same energy and pulse settings, with variable contact cooling. Protective cooling parameters, for each degree increment, ranging from 0 to 25°C were studied. Immunohistochemistry (IHC), Western blot and PCR were performed to evaluate the effects of superficial cooling on Hsp47, and Hsp70 expressions.

Results

Our data showed the extent of topical cooling needed to produce a thermal effect at different depths in the dermis, quantified by the expression of Hsp47 and Hsp70. Significant Hsp expression was observed with cooling of 13°C and warmer; no identifiable cellular reaction was observed when cooling below 5°C. There was no evidence of epidermal injury when treating the skin with any protective cooling ranging from 0 to 25°C.

Conclusion

Our data would suggest contact cooling temperatures 5°C and below completely protects through the entire dermis. There was no evidence of epidermal injury with protective cooling at any temperature between 0 and 25°C. Warmer temperatures are safe and adequately protect the epidermis in this model. Lasers Surg. Med. 39:504–512, 2007. © 2007 Wiley‐Liss, Inc.
Low‐intensity laser irradiation stimulates bone nodule formation via insulin‐like growth factor‐I expression in rat calvarial cells
Authors: Shimizu Noriyoshi , Mayahara Kotoe , Kiyosaki Takeshi , Yamaguchi Akikuni , Ozawa Yasuhiro , Abiko Yoshimitsu
Published: July 2007

Background and Objective

We previously reported that low‐intensity laser irradiation stimulated bone nodule formation through enhanced cellular proliferation and differentiation. However, the mechanisms of irradiation are unclear. Thus, we attempted to determine the responsibility of insulin‐like growth factor (IGF)‐I for the action observed.

Study Design/Materials and Methods

Osteoblast‐like cells were isolated from fetal rat calvariae and cultured with rat recombinant (r) IGF‐I, IGF‐I‐antibody (Ab), and/or the cells were irradiated once (3.75 J/cm2) with a low‐intensity Ga‐Al‐As laser (830 nm). The number and area of bone nodules formed in the culture were analyzed, and IGF‐I expression was also examined.

Results

Treatment with rIGF‐I significantly stimulated the number and area of bone nodules. This stimulatory effect was quite similar to those by laser irradiation, and this stimulation was abrogated dose‐dependently by treatment with IGF‐I‐Ab. Moreover, laser irradiation significantly increased IGF‐I protein and gene expression.

Conclusion

The stimulatory effect of bone nodule formation by low‐intensity laser irradiation will be at least partly mediated by IGF‐I expression. Lasers Surg. Med. 39:551–559, 2007. © 2007 Wiley‐Liss, Inc.
Polymer/Laponite Composite Latexes: Particle Morphology, Film Microstructure, and Properties
Authors: Negrete‐Herrera Norma , Putaux Jean‐Luc , David Laurent , Haas Felix De , Bourgeat‐Lami Elodie
Published: July 2007

Transparent film materials with excellent mechanical and thermal properties were elaborated by drying a latex suspension of armored polymer/Laponite composite particles. Low‐temperature TEM observation of ultrathin cross‐sections of the films indicated a unique network morphology characterized by a “honeycomb” distribution of the Laponite platelets remindful of the original particles morphology.

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Sub‐Micrometer Sized Hairy Latex Particles Synthesized by Dispersion Polymerization Using Hydrophilic Macromolecular RAFT Agents
Authors: Bathfield Maël , D'Agosto Franck , Spitz Roger , Charreyre Marie‐Thérèse , Pichot Christian , Delair Thierry
Published: July 2007

Dispersion polymerization of n‐butyl acrylate has been performed in a mixture of ethanol and water in the presence of poly(N‐acryloylmorpholine) (polyNAM). These hydrophilic polymer chains are synthesized by the RAFT process and thus incorporate well‐defined chain ends. The dithioester ω‐end group is used as an efficient chain transfer agent under dispersion polymerization conditions to produce hairy poly(n‐butyl acrylate) latex particles. Moreover, pre‐functionalization of the polyNAM chains on the α‐end by a carbohydrate derivative is also achieved to obtain directly functionalized particles according to the same strategy.

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Etiological musculo‐skeletal factor in focal dystonia in a musician's hand: A case study of the right hand of a guitarist
Authors: Leijnse Joris N.A.L. , Hallett Mark
Published: July 2007

A case study is presented in which a focal hand dystonia seems to have developed in the right hand of a classical guitarist as a result of a neuromuscular peripheral defect caused by trauma. The trauma was a near total perforation of the first web space by a splinter. Healing was uneventful without apparent functional complications. Two years later the patient noticed difficulties in extending the index in playing, for which he received various unsuccessful treatments during seven years. However, we found more severe dystonic symptoms (cocontractions) in the thumb than in the index during playing, which correlated with an undiagnosed insufficiency in the flexor pollicis brevis (FPB). This defect allowed proposing a biomechanical analysis of compensations for diminished thumb control in playing, which would explain the dysfunction in the index in playing as overcompensation for the thumb problem. If this analysis is correct, the etiology of the case can be traced back to underlying multiarticular control problems in the thumb caused by an insufficient FPB. This defect was considered irrepairable. It was concluded that even with knowledge of the underlying cause, a potentially successful treatment of the dystonia might not exist in this case. The case would demonstrate that task‐specific hand dystonias can arise as overcompensations for (peripheral) neuro‐musculoskeletal defects. The case is illustrated by videos of playing and functional thumb tests. © 2007 Movement Disorder Society
Combining spin echoes with gradient echoes in the context of the global coherent free precession pulse sequence
Authors: Rehwald Wolfgang G. , Salerno Michael , Chen Enn‐Ling , Sievers Burkhard , Kim Raymond J. , Judd Robert M.
Published: July 2007

To extend the signal longevity of magnetically excited spins in flowing fluids while in a state of global coherent free precession (GCFP), a refocusing radiofrequency (RF) pulse and bipolar gradient waveforms were combined with the GCFP sequence. The data demonstrate that RF refocusing in the presence of flowing blood is possible, but the improvement in signal amplitude depends on the static magnetic field homogeneity along the direction of motion and the displacement of the spins between the excitation and the RF refocusing pulse, as well as displacement during subsequent RF refocusing pulses. The least amount of phase dispersion and thus the longest lasting signal is obtained with the shortest echo spacing where only one line of data is recorded between two RF refocusing pulses. This approach was successfully used in a phantom and in vivo to image fast and slow blood flow. Depending on the experimental conditions, signal persistence is improved significantly compared to playing the same sequence without RF refocusing, but the improvement is limited by the product of blood flow velocity and the time between RF refocusing pulses. Magn Reson Med 58:82–91, 2007. © 2007 Wiley‐Liss, Inc.
Modifying and managing the surface properties of polymers
Authors: Hutchings Lian R , Narrianen Amilcar Pillay , Thompson Richard L , Clarke Nigel , Ansari Imtiyaz
Published: July 2007

An ongoing challenge in polymer science is the preparation of materials with bespoke surface properties which differ from that of the bulk, for example hydrophobicity, wettability, chemical resistance, adhesion or biocompatibility. We highlight here recent efforts in the design, development and application of (multi)end‐functionalized polymers as additives for the efficient modification of polymer surface properties. Aryl‐ether moieties bearing up to eight functional groups have been used as initiators for the controlled polymerization of both styrene and methyl methacrylate by atom transfer radical polymerization (ATRP) and of lactide by ring opening polymerization (ROP). The resulting polymers have been used as additives to modify the surfaces of the corresponding bulk polymers. Fluorinated polymer surfaces are particularly appealing in terms of their liquid repellence, chemical inertness and low coefficient of friction. When an additive consisting of a low molecular weight polystyrene chain, end‐capped with four C8F17 groups, is present in a matrix of polystyrene at levels as low as 0.1%, near polytetrafluoroethylene‐like surface properties result. Copyright © 2007 Society of Chemical Industry
Enhancement of wettability in low density polyethylene films using low pressure glow discharge N2 plasma
Authors: Sanchis Rosa M. , Calvo Oscar , Sánchez Lourdes , García David , Balart Rafael
Published: July 2007

Low pressure glow discharge nitrogen plasma has been used to improve wettability in a low density polyethylene (LDPE) film for technical applications. The plasma treatment was carried out at a power of 300 W for different exposure times in the 1–20 min range. Wettability changes were analyzed using contact angle measurements. In addition to this, plasma‐treated samples were subjected to an aging process to determine the durability of the plasma treatment. X‐ray photoelectron spectroscopy, atomic force microscopy, and scanning electron microscopy were used for surface characterization. The nitrogen plasma treatment considerably reduced contact angle values thus indicating an increase in surface wettability. The spectroscopic study showed presence of oxygen‐based species on the plasma‐treated samples, which are mainly generated after the plasma treatment as a consequence of air exposure. These polar species contribute to improve surface functionalization, but this is almost lost during aging due to the hydrophobic recovery process. Microscopic studies revealed that also small changes in surface roughness occurred during the plasma treatment but these are very low compared to surface activation. The results confirmed that low pressure nitrogen can be considered as an environmentally efficient process to improve wettability in low density polyethylene films. © 2007 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 45: 2390–2399, 2007
Vapor‐induced spreading dynamics of adsorbed linear and brush‐like macromolecules as observed by environmental SFM: Polymer chain statistics and scaling exponents
Authors: Gallyamov Marat O. , Tartsch Bernd , Mela Petra , Potemkin Igor I. , Sheiko Sergei S. , Börner Hans , Matyjaszewski Krzysztof , Khokhlov Alexei R. , Möller Martin
Published: July 2007

Scaling exponents ν, that describe the correlation between mean square end‐to‐end distances and contour lengths of macromolecules, were determined by statistical analysis of scanning force micrographs of single linear poly(2‐vinylpyridine) and brush‐like poly(butanoate‐ethyl methacrylate)‐graft‐poly(n‐butyl acrylate) macromolecules adsorbed on mica. Using an atmosphere‐controlled scanning force microscope, single adsorbed molecules were collapsed and re‐expanded upon being exposed to alcohol and water vapor, respectively. This manipulated collapse‐unfolding was used to equilibrate the molecular structure/conformation. The in situ and real‐time scanning force microscopy analysis allows the scientist to quantitatively characterize end‐to‐end distances and contour lengths of the molecules directly on the image and to observe differences in the spreading dynamics for the two types of macromolecules. A distinct difference has been observed between the expanded two‐dimensional (2D) conformations of linear and brush‐like polymer chains. Whereas a scaling exponent ν of 0.73 was found for the expanded 2D conformation of the linear molecules, a ν‐value of 0.53 was determined for the expanded 2D conformation of the seemingly stiffer brush‐like molecules. A theoretical explanation of the differences between the 2D conformations of brush‐like and linear macromolecules is proposed here. © 2007 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 45: 2368–2379, 2007
Porous SiOCH, SiCH and SiO2 Etching in High Density Fluorocarbon Plasma with a Pulsed Bias
Authors: Raballand Vanessa , Cartry Gilles , Cardinaud Christophe
Published: July 2007

The effect of radio frequency bias pulsing on porous SiOCH, SiCH and SiO2 etching using inductively coupled fluorocarbon plasmas was investigated. It was found that pulse frequency had only a small influence on material etch rates. However, pulse duty cycle, defined as the time during which a bias is applied over the total period, clearly modified etch rates and selectivities. Indeed, etch selectivities between porous SiOCH and SiCH or SiO2 were considerably improved when the duty cycle was decreased. This enhancement was associated with relatively high porous SiOCH etch rates, and pattern transfers under low duty cycle conditions proved to be successful. To better understand the pulse process, surface analysis was also realised. According to XPS analysis, the material surface structure was found to be similar after etching in continuous or in pulsed mode. However, fluorocarbon species on material surfaces were fluorine richer after etching in the pulsed mode.

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Experimental Characterisation of the Plasma Absorption Probe
Authors: Scharwitz Christian , Böke Marc , Hong Suk‐Ho , Winter Jörg
Published: July 2007

The plasma absorption probe has been developed to provide a fast and efficient diagnostic tool for the characterisation of discharges, especially of reactive plasmas. Unlike Langmuir probes, the plasma absorption probe measures electron densities in reactive plasmas undisturbed by coatings of the probe surface. It consists of a semirigid coaxial cable with protruding inner conductor as an antenna, covered by a dielectric tube. The measurement principle is based on active resonance spectroscopy. A network analyser feeds the coaxial cable with HF of variable frequency and the power reflection spectrum is detected. At resonant frequencies, characteristic for the discharge, absorption signals are observed. In this paper, we present measurements of the plasma absorption probe for various discharge conditions and we evaluate the probes' further potential for the analysis of reactive plasmas.

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Pulmonary testing using peak flow meters of very low birth weight children born in the perisurfactant era and school controls at age 10 years
Authors: Palta Mari , Sadek‐Badawi Mona , Madden Kathleen , Green Christopher
Published: July 2007

We determined lung function at age 10 years in very low birthweight (VLBW, ≤1,500 g) children and controls, and compared the sensitivity to detect subgroup differences by peak expiratory flow (PEF), forced expiratory volume in one second (FEV1), forced vital capacity (FVC) and their diurnal variation. VLBW children were recruited across the perisurfactant era at admission to six NICUs in Wisconsin and Iowa, and controls from area classrooms. Two hundred sixty five VLBW children and 360 controls were tested by the Jaeger AM1 peak flow meter at age 10 years. Two hundred six VLBW and 79 controls had additional home monitoring. Abnormality was defined as observed/predicted ratio <0.8 for PEF, FEV1, and FVC, and by criteria of Pelkonen for diurnal PEF variation. VLBW children were compared to controls, VLBW children with bronchopulmonary dysplasia (BPD) to those without, and those with respiratory conditions to those without. PEF and FEV1 showed high reproducibility (intraclass correlations, ICC 0.75–0.83). Controls and VLBW children with and without BPD differed significantly on all measures. Baseline test results did not differ across birth years, but PEF variation was less after surfactant availability (P = 0.04). Observed over predicted FEV1 was the most sensitive in detecting differences between groups (P < 0.001), with mean (s.d.) 0.97 (0.12) for controls, 0.88 (0.14) for VLBW children without BPD, and 0.78 (0.13) for those with BPD. Odds ratios for abnormality were especially high with respiratory medication use during the first 5 years of life, 4.4 (95% CI: 2.0–9.8) for FEV1 and 5.1 (95% CI: 2.0–13.2) for diurnal PEF variation. Our results show that respiratory abnormalities persist to at least age 10 years for VLBW children born in the surfactant era. Pediatr Pulmonol. 2007; 42:819–828. © 2007 Wiley‐Liss, Inc.
Placebo‐controlled study of montelukast and budesonide on short‐term growth in prepubertal asthmatic children
Authors: Pedersen Søren , Agertoft Lone , Williams‐Herman Debora , Kuznetsova Olga , Reiss Theodore F. , Knorr Barbara , Dass S. Balachandra , Wolthers Ole D.
Published: July 2007

Background

Inhaled corticosteroids and anti‐leukotriene agents are widely used in the treatment of pediatric asthma. Although data on the effect of corticosteroids on growth are available, there are few such data on anti‐leukotriene agents. The aim of this study was to assess the influence of montelukast on short‐term lower leg growth rate (LLGR) in prepubertal children with asthma.

Methods

Forty‐two boys (6‐ to 12‐year old) and 29 girls (6‐ to 11‐year old) with mild asthma were randomized to 1 of 2 crossover arms, with two treatment sequences per arm: montelukast 5 mg once daily/placebo or inhaled dry powder budesonide 200 µg twice daily/placebo. Budesonide was used as a positive control to ensure that the method was sensitive enough to detect a suppression of LLGR. The 3‐week double‐blind treatment period was followed by a 3‐week washout. Primary outcome was LLGR over the 3‐week treatment, measured by knemometry.

Results

Ninety‐four percent of patients completed the study. Mean LLGR was similar between patients receiving montelukast and placebo treatments: mean difference, −0.02 mm/week [95% confidence interval −0.14, 0.11]. Mean LLGR in patients receiving budesonide was significantly less than for those receiving placebo (difference of −0.16 mm/week [−0.25, −0.06], P = 0.002). Mean LLGR was similar for patients taking placebo in the two arms (0.43 and 0.44 mm/week).

Conclusion

Montelukast 5 mg did not significantly affect short‐term LLGR in prepubertal children. Pediatr Pulmonol. 2007; 42:838–843. © 2007 Wiley‐Liss, Inc.
Sunflowers as a trap crop for reducing soybean losses to the stalk borer Dectes texanus (Coleoptera: Cerambycidae)
Authors: Michaud JP , Qureshi Jawwad A , Grant Angela K
Published: July 2007

Larvae of Dectes texanus LeConte cause significant losses to soybean production in the American High Plains by girdling the stalks of mature plants at their base, causing them to lodge. The authors demonstrated that cultivated sunflowers can reduce rates of D. texanus infestation in adjacent soybean fields because adult females prefer sunflower over soybean for feeding and oviposition. Since females do not avoid ovipositing in plants already containing their own eggs or those of conspecific females, sunflower plants can accumulate multiple eggs, and subsequent larval combat typically results in the survival of only one. In west central Kansas, planting one half of a center pivot irrigated field to sunflower in 2004 significantly reduced infestation of soybean plants in the other half of the field within 200 m of the crop border. Beyond 200 m from the sunflowers, the rate of soybean infestation increased significantly. Planting sunflowers in the non‐irrigated corners of a center pivot irrigated soybean field in 2005 reduced D. texanus infestation of soybeans by 65% compared with a control field without adjacent sunflowers. Surrounding a 0.33 ha soybean field with six rows of sunflowers in 2006 reduced soybean infestation to < 5% of plants, compared with 96% of sunflower plants. These results reveal that sunflowers can reduce D. texanus infestation in adjacent soybeans by acting as an ‘ovipositional sink’. Further research is warranted to determine the optimum crop area proportions and spatial configurations that will maximize the efficacy of a sunflower trap crop to reduce soybean losses due to D. texanus‐induced lodging. Copyright © 2007 Society of Chemical Industry
Maintenance of female dominance in blue‐eyed black lemurs (Eulemur macaco flavifrons) and gray bamboo lemurs (Hapalemur griseus griseus) under semi‐free‐ranging and captive conditions
Authors: Digby Leslie , Mclean Stevens Alexandra
Published: July 2007

Several species of Malagasy prosimians are characterized by female dominance, an unusual trait among mammals. We compare the extent to which female dominance is displayed and the mechanisms that are used to maintain dominance in the frugivorous blue‐eyed black lemurs (Eulemur macaco flavifrons) and the folivorous gray bamboo lemurs (Hapalemur griseus griseus) housed at the Duke Lemur Center. All dominant–submissive interactions were recorded during 448 hr of focal animal observations. Both species of lemurs exhibited clear patterns of female dominance. However, the two species used aggressive dominance (defined as aggression+submission) and social dominance (defined as submission in the absence of aggression) to different extents in maintaining hierarchies within each group. The adult female blue‐eyed black lemurs used aggressive dominance (e.g., chase, cuff, bite) in more of their dominance interactions (66%) than did the adult female gray bamboo lemurs (40%). In both species, rates of aggressive dominance interactions were higher during feeding versus nonfeeding periods and while in smaller outdoor runs versus larger natural habitat enclosures, but the differences were not significant. Overall blue‐eyed black lemurs exhibit a more aggressive form of female dominance compared to the gray bamboo lemur. Zoo Biol 26:345–361, 2007. © 2007 Wiley‐Liss, Inc.
A solution thermodynamic study of soybean oil/solvent systems by inverse gas chromatography
Authors: King Jerry W. , List Gary R.
Published: July 2007

Inverse gas chromatography (IGC) has seen wide application in the characterization of molten polymers, fibrous materials, and natural products, such as proteins and carbohydrates, over the past fifteen years. This study describes a relatively simple IGC technique for evaluating solute‐solvent interactions using a refined soybean oil as a solvent. Utilizing soybean columns that are 5–20% by weight of the inert support has allowed the determination of a number of thermodynamic solution parameters for 22 solute‐solvent pairs in the temperature range of 55–125°C. Weight and mole fraction activity coefficients, along with Henry's Law constants at infinite dilution, are presented for six solute classes. In general, activity coefficients increase with carbon number for n‐alkanes, alkyl‐substituted benzenes, and n‐alkanoic acids at all temperatures investigated, while the reverse is found for the n‐alkanols. The activity coefficient data indicate that aromatic solutes, chlorinated hydrocarbons, ketones, and cyclohexane can readily dissolve soybean oil. Calculated heats of mixing for n‐alkanols were found to be positive (to 2.84 kcal/mole) while recorded enthalpic interactions were weak for aromatic solutes, lower alkanes, and chlorinated hydrocarbons. The relevance of the above data to such problems as oil dissolution and solvent devolatilization are discussed.
Preparation and surface active properties of amphipathic compounds with two sulfate groups and two lipophilic alkyl chains
Authors: Zhu Yun‐peng , Masuyama Araki , Okahara Mitsuo
Published: July 2007

These compounds with various connecting groups between the two lipophilic groups were prepared by the reaction of glycol diglycidyl ethers with long‐chain alcohols, followed by sulfation with chlorosulfonic acid or with a mixture of chlorosulfonic acid and acetic acid. The Krafft point of all these new amphipathic compounds was below 0°C, and they had good water solubility. These compounds were superior in surface active properties to general anionic surfactants with one lipophilic chain and one hydrophilic group, such as sodium dodecylsulfate. The effect of the structure of the connecting group on CMC, γCMC, foaming properties and wetting ability was investigated. They also showed excellent lime‐soap dispersing ability.
Determination of true iodine number of oils with conjugate unsaturation by use of hypochlorous acid reagent
Authors: Chowdhury R. Basu , Mukherjee S.
Published: July 2007

Hypochlorous acid reagent has conveniently been used for the determination of total unsaturation in oils containing conjugated double bonds. The use of 0.1 N HOCl reagent normally employed for oils with isolated double bonds leads to incomplete absorption, and the increase in concentration and reaction period gives desirable results in the presence of mercuric acetate catalyst. A 1‐hr. reaction period with 0.3 N HOCl reagent in the presence of 2.5% solution of the catalyst is recommended. A sample size varying between 0.07–0.1 g. and a 300–400% excess reagent should be employed to obtain reliable results. This procedure can be effectively used for determining the total unsaturation of tung oil, isomerized fatty acids, and dehydrated castor oil and can be employed for detecting the adulteration in commercial samples of tung oil, which cannot be ordinarily detected by the determination of the partial iodine number with the help of conventional procedures.
Solubility of monoglycerides in oil and its relation to the production of global edible spread
Authors: Hellman N. N. , Zobel H. F. , Senti F. R.
Published: July 2007

Solubility data have been presented for monostearin, monopalmitin, and monoglycerides of triple‐pressed stearic acid and hydrogenated lard in cotton‐seed oil. Monoglyceride precipitated from solution by quick chilling became less soluble after tempering 18 hrs. at 45°C. Decreased solubility was related to increased crystallinity as determined by X‐ray diffraction. Solubility data thus confirmed conclusions previously reported that tempering operates to improve global spread primarily through recrystallization which is now shown to involve converting precipitates of low degree of molecular order into more perfect crystals.
Effect of water activity on autoxidation of raw peanut oil
Authors: Gopalakrishna A. G. , Prabhakar J. V.
Published: July 2007

The effect of water activity (aw) on rate of autoxidation of raw peanut oil at 37 C was studied. Up to 3 weeks of storage, no marked effect of aw on the rate of peroxide formation was noticeable. However, with prolonged storage, the rate of peroxide formation decreased rapidly at aw of 0.67 and higher as compared to aw of 0.50 and lower. At the end of 9 weeks’ storage, the peroxide value at aw=0.02‐0.50 was in the range of 31–35, while it was only ca. 10 at 0.79 and 0.92 aw. There was no noticeable influence of aw on the rate of free fatty acid formation. The oil stored for 7 weeks at 0.02 and 0.11 aw had fresh flavor, although the peroxide values were high; whereas the oils at 0.79 and 0.92 aw were stale, although the peroxide values were less than 10. The anisidine value at 0.02 aw (348) was higher than at 0.92 aw (62). The carbonyl values at 0.02 and 0.11 aw were also higher (1090, 1021) than at 0.79 and 0.92 aw (573, 780). The results indicate that the protective effect on the oil against peroxide formation at high aw may be due to certain components present in raw peanut oil.
Enzymatic glycerolysis of a triglyceride in aqueous and nonaqueous microemulsions
Authors: Holmberg Krister , Lassen Bo , Stark Maj‐Britt
Published: July 2007

Enzymatic solvolysis of a model triglyceride, palm oil, was performed in microemulsions containing isooctane, sodiumbis(2‐ethylhexyl)sulfosuccinate (AOT), palm oil and a combination of water and glycerol as the polar component. Using a 1,3‐specific lipase both hydrolysis, leading to the formation of fatty acid and one mole of monoglyceride, and glycerolysis, giving three moles of monoglyceride, occur. The reaction was very slow in a completely nonaqueous system. Addition of a small amount of water led to an increased rate of glycerolysis, in addition to hydrolysis. It was found that by using3H labelled material reaction products originating from the two reactions were formed in equimolar amounts. The products probably emanate from a common intermediate. The molar ratio, R, of water and glycerol to surfactant turned out to be critical, optimum R‐value being 3.4. Four different lipases, one from porcine pancreas and three of fungal origin, were tested. No marked differences in ratio of monoglyceride to fatty acid formed were obtained, indicating that the ratio between glycerolysis and hydrolysis is constant regardless of the lipase used.
Determination of fatty acid composition of amaranthus species
Authors: Ayorinde Folahan O. , Ologunde Michael O. , Nana Erick Y. , Bernard Brian N. , Afolabi Oladapo A. , Oke Olusegun L. , Shepard Robert L.
Published: July 2007

Fatty acid compositions of the seed oils from eighteen vareties of amaranthus species have been determined after room temperature transesterification. Consistent with earlier studies, wide variations in the fatty acid composition are reported, and appear to be agronomically related. All variaties show significant levels (2–5%) of squalene and a combined linoleic acid and olaic acid occurrence of between 70–‐80%. This study represents the frist reported fatty acid composition of grain amaranthus cultivated in West Africa.
Hydrozirconation of oleyl alcohol
Authors: Karlsson Susanne , Hallberg Anders , Gronowitz Salo
Published: July 2007

Hydrozirconation of oleyl alcohol gave a mixture of the ω‐and γ‐zirconium‐stearyl alcohols. The zirconium alkyl bonds were cleaved by reaction with D2O, Br2 or CO‐Br2‐2‐methoxyethanol. 18‐Bromo‐stearyl alcohol (X) and 3‐bromo‐stearyl alcohol (IX) were isolated after bromination and 2‐methoxyethyl 19‐hydroxynonadecanoate (XII) and dihydro‐3‐pentadecyl‐2(3H)‐furanone (XIII) after carbonylation.
Potentiometric titration of long chain quaternary ammonium compounds using sodium tetraphenyl borate
Authors: Wang C. N. , Metcalfe L. D. , Donkerbroek J. J. , Cosijn A. H. M.
Published: July 2007

Current methods for determining the activity of long chain quaternary ammonium compounds (QACS) are based either on dye partition, titration, or colorimetric analysis. The two major disadvantages of these methods are the disparity of partition coefficients among differently constituted QACS and the difficulty in detecting visual end points. Some potentiometric titration methods for QACS have been reported in the literature. However, back titration techniques, as well as complicated electrode systems, are generally involved.

A new potentiometric titration system is presented which uses aqueous sodium tetraphenylborate (TPB) solution as a titrant and a platinum‐platinum electrode system to detect the end point. Standard potentiometric titration instruments may be used for this method. This new potentiometric method is superior in precision and accuracy to visual (colorimetric) methods.
The analysis of fatty alcohols and acids asp‐(methylthio)‐benzoate esters
Authors: Willett J. D. , Brody E. P. , Knight M. M.
Published: July 2007

Thep‐(methylthio)‐benzoate ester of fatty alcohols is investigated. This derivative shows either a molecular ion or M‐168 m/e peak in its mass spectrum and mixtures may be qualitatively analyzed directly by mass spectrometry. The compounds absorb strongly in the ultraviolet, allowing quantitative analysis by high performance liquid chromatography to 200 pmol.
Rapid determination of wax in sunflower seed oil
Authors: Morrison W. H.
Published: July 2007

A rapid turbidimetric method for determining wax content in sunflower seed oil is described. Oil is heated to 130 C, filtered, and after cooling, added to an equal volume of acetone. The mixture is then reheated under tap water to dissolve waxes which may have crystallized and is placed in an ice bath for 5 min. Turbidity is then measured and ppm wax is read from a previously prepared calibration curve. The amount of wax as determined by the turbidimetric method is in good agreement with the gas liquid chromatographic values.
Analytical13C NMR spectroscopy of fatty quaternary amines
Authors: Fairchild E. H.
Published: July 2007

Natural abundance13C nuclear magnetic resonance spectroscopy (CMR) has been used for the rapid, nondestructive analysis of fatty quaternary ammonium compounds. Quantitative analysis of mixtures of mono‐, di‐and tri‐fatty ammonium chlorides can be accommpublished under conditions that do not involve heat or extremes of pH and that are independent of solvent present. In order to determine optimal conditions for quantitative studies, carbon spin lattice relaxation times (T1) and nuclear Overhauser effects (NOE) were determined for each of the components. The method of internal standard addition was used to determine reproducibility and accuracy of the method for the measurement of mono‐and tri‐fatty quaternary components in material consisting predominantly (i.e., greater than 90%) of di‐fatty‐dimethyl ammonium chloride.
Effect of culture conditions on fatty acid composition in lipids produced by the yeastcryptococcus albidus var. albidus
Authors: Hansson Lena , Dostálek Milan
Published: July 2007

The influence of culture conditions on the fatty acid composition in lipids produced by Cryptococcus albidus var. albidus CBS 4517 was studied.

The major fatty acids in C. albidus var. albidus were oleic (18:1), linoleic (18:2) and palmitic (16:0) acid. The relative amounts of fatty acids produced varied considerably during growth and lipid accumulation phases in nitrogen‐limited as well as excess‐nitrogen cultures. The degree of unsaturation correlated to the lipid content in the biomass and decreased with increasing amounts of cellular lipid. After glucose exhaustion, no further changes in the fatty acid composition nor in the lipid content of the cells were observed. A number of carbon and nitrogen sources could be utilized for lipid synthesis, but they influenced the fatty acid composition only to a minor extent.
An improved ashing procedure for the determination of heavy metals in edible oils
Authors: Tsai Wei‐Chong , Lin Chia‐Pao , Shiau Lihwiuan , Pan Shuh‐Der
Published: July 2007

An accurate, reliable, and simple method was described for the determination of Pb, Cu, Cd, Mn, Zn, an d Fe in edible oils by atomic absorption spectrophotometry following burning of the sample in a restricted air supply. Recoveries for the six heavy metals by the proposed methods were about 100%. The relative standard deviation of the analysis for the lead at the level of 0.074 ppm was 6%, and the copper at the levels of 0.064 ppm and 0.158 ppm were 7% and 2%, respectively. The recovery of lead was found to be suppressed by the presence of a large quantity of iron in the oil, but the suppression was alleviated by adding a Mg(NO3)2 solution to the charred residue before ashing.