bluuebunny/crossref_metadata_2025 huggingface dataset:
A Different Kind of Profession
Authors: Luey Beth
Published: July 2008

Is journal editing a profession? If so, it is not – and should not be – a traditional one, like law or medicine. Rather, it should be a profession open to innovation and talent and transparent to those who interact with it as authors, subscribers, and readers. This article, which began as the keynote address at the 2006 meeting of the Council of Editors of Learned Journals, examines the characteristics of the professions, the ways they are – and are not – appropriate to journal editing, and some possibilities for increasing professionalism without encumbering ourselves with its less desirable features.
Oceanic Slab Melting and Mantle Metasomatism
Authors: Scaillet Bruno , Prouteau Gaëlle
Published: July 2008

Modern plate tectonic brings down oceanic crust along subduction zones where it either dehydrates or melts. Those hydrous fluids or melts migrate into the overlying mantle wedge trigerring its melting which produces arc magmas and thus additional continental crust. Nowadays, melting seems to be restricted to cases of young (<50 Ma) subducted plates. Slab melts are silicic and strongly sodic (trondhjemitic). They are produced at low temperatures (<1000°C) and under water excess conditions. Their interaction with mantle peridotite produces hydrous metasomatic phases such as amphibole and phlogopite that can be more or less sodium rich. Upon interaction the slab melt becomes less silicic (dacitic to andesitic), and Mg, Ni and Cr richer. Virtually all exposed slab melts display geochemical evidence of ingestion of mantle material. Modern slab melts are thus unlike Archean Trondhjemite–Tonalite–Granodiorite rocks (TTG), which suggests that both types of magmas were generated via different petrogenetic pathways which may imply an Archean tectonic model of crust production different from that of the present-day, subduction-related, one.
Three-Dimensional Reconstruction of Single Particle Electron Microscopy: The Voltage Sensitive Sodium Channel Structure
Authors: Ueno Yutaka , Sato Chikara
Published: July 2008

Single particle analysis in electron microscopy allows direct observation of the reconstructed three-dimensional structures of protein molecules. This method enables a more comprehensive study of membrane proteins which have been problematic in structural studies using X-ray crystallography. These membrane proteins include the voltage-sensitive ion channel proteins, which play an important rule in neural activities, and have great medical significance. The method described is supported by the development of cryo-electron microscopy and the angular reconstitution method. This review summarizes certain principles governing single particle analysis employing angular reconstitution. This method was applied to our study of the voltage-sensitive sodium channel, and the results are discussed. With improvements in resolutions and statistical analyses, the single particle technique is considered to be advantageous in studies of the structural changes and molecular interactions of protein molecules.
The Origin of Life I: When and Where Did it Begin?
Authors: Davies Paul
Published: July 2008

For decades most scientists assumed that life emerged billions of years ago in a “primordial soup” somewhere on the Earth's surface. Evidence is mounting, however, that life may have begun deep beneath the surface, perhaps near a volcanic ocean vent or even inside the hot crust itself. Since there are hints that life's history on Earth extends back through the phase of massive cosmic bombardment, it may be that life started on Mars and came here later, perhaps inside rocks ejected from the Red Planet by large impacts. The traffic of intact rocks between Mars and Earth is now an established fact, and experiments confirm that microbes could survive the rigours of the journey through space if cocooned within such material. Unfortunately, this planetary cross-contamination compromises astro-biologists’ hope of finding a second genesis in the solar system.
Single Crystal Time-of-Flight Neutron Diffraction
Authors: Peters J. , Jauch W.
Published: July 2008

The last century has seen a large development in diffraction techniques. The time-of-flight neutron diffraction method is now so advanced that it provides high precision results for position and thermal parameters, which are complementary to other diffraction results from X-ray sources. Here we review the history of neutron sources, the difficulties encountered with the time-of-flight technique and an outlook for applications. In this context, we will show the limitations of existing neutron sources and the expected advantages of new spallation neutron sources. An overview of all corrections to be taken into account with the wavelength-sorting technique will be presented as well as actual results, how to overcome such problems, and the special difficulty of integration of three-dimensional Bragg peaks.
Comparative Biology of γδ T Cells
Authors: Chen Zheng W.
Published: July 2008

Accumulative evidence suggests that resident γδ T cells in epithelia are biologically distinct from systemic γδ T cells in the circulation. Murine resident γδ T cells have innate immune characteristics and play an important role in tissue homeostasis after damages. In contrast, a unique subset of circulating γδ T cells in primates, like αβ T cells, can mount adaptive immune responses in infections. This article compares biological features between resident and circulating γδ T cells.
Microporous Materials
Authors: Attfield Martin P.
Published: July 2008

All materials possess interatomic or interionic voids that are typically too small for any molecular species to enter. However, there is a class of crystalline materials that contain internal voids, and apertures, that are large enough for molecular species to enter and pass through. These materials are termed microporous and form a highly diverse group of compounds that may be synthesised or occur as natural minerals. The composition of microporous materials ranges from being exclusively inorganic to inorganic-organic hybrids and their applications vary from 1 Mton annual usage in detergents, to hosts for superconducting carbon nan-otubes. In this contribution, new and mature aspects of the synthesis, scope, modification and application of microporous materials are covered to provide the reader with an overview of this exciting field of materials chemistry.
Development of the Sensory Organs
Authors: Francis-West Philippa H. , Ladher Raj K. , Schoenwolf Gary C.
Published: July 2008

The sensory organs – the eye, ear, and nose- are formed, in part, from ectodermal thickenings: placodes. Their development is distinct from that of other regions of the developing body and they are essential for the development of other structures. For example, the olfactory placode which gives rise to the nose is essential for the functional development of the reproductive organs and hence fertility. Recently much progress has been made in the understanding of placode development, at both a molecular and embryological level. This is important as abnormal development of placodes occurs in a number of human syndromes. Furthermore, knowledge of placode development will give insight into therapeutic strategies to prevent degenerative change such as deafness. This review highlights the current knowledge of placode development and the future challenges in unravelling the cascades of signalling interactions that control development of these unique structures.
Resistance to Antifolates in Plasmodium Falciparum, the Causative Agent of Tropical Malaria
Authors: Warhurst David C.
Published: July 2008

Every year there are 270 million clinical attacks of malaria and 2 million deaths, caused by the protozoan Plasmodium falciparum. Most of these cases occur in Africa. Chloroquine-resistance has led to reliance on antimalarial antifolates, in particular the synergistic combination sulfadoxine/ pyrimethamine (S/P) which targets enzymatic synthesis of folate co-factors through dihydropteroate synthase (DHPS) and dihydrofolate reductase (DHFR). Resistance to S/P is now increasing and replacement antimalarials are needed. Crystal structures are not yet available for these key enzymes in the folate pathway. This review focuses on the activity of drugs on DHFR in malaria parasites, attempts to interpret differences in activity of pyrimethamine and its related drugs, and to clarify how residue changes due to point mutations determine the development of resistance.

In homology-modelled P. falciparum DHFR (PfDHFR), the typical structure of four α-helices, 8-stranded β-sheet, four Loops and eight Turns is clearly seen. Long polar sequences specific for Plasmodium are inserted in Turns 1 and 2. Structures immediately concerned in drug binding are β-A, L1, α-B, α-C, T-3, β-E, α-F, and β-F. The roles of several mutations associated with resistance are discussed. In view of sequence differences in turn 3 in PfDHFR and in the human enzyme, and the marked interaction with residues of T3 of the experimental flexible antifolate WR99210 effective in pyrimethamine and cycloguanil resistance, further drug development in this area is indicated.
Weak Organic Acids: A Panoply of Effects on Bacteria
Authors: Hirshfield Irvin N. , Terzulli Stephanie , O'Byrne Conor
Published: July 2008

Weak organic acids have been used for centuries to preserve foods, but only recently has the possible mechanism for bacterial growth inhibition been investigated. Although the lowering of internal pH was favored as the cause of growth inhibition, the emphasis has shifted to the anion and its specificity. There are a number of applications of weak organic acids to foods and in the food industry be they pre-or postharvest, However, there is concern that the ability of foodborne pathogens to adapt to these acids may allow longer survival in these commodities and also to better survive transit through the gastric acid barrier of the stomach. Genomic and proteomic approaches have been applied to the identification of genes and proteins that may allow prokaryotes to cope with organic acid stress. These technologies in combination with genetic approaches may provide better identification of genes essential for survival to organic acids. These acids may have other roles: they can induce phenotypic antibiotic resistance, and the high concentrations of these acids in the colon may signal a relationship to diet, colonic microflora, and human health.
Morphological Changes to Escherichia Coli O157:H7, Commensal E. coli and Salmonella spp in Response to Marginal Growth Conditions, with Special Reference to Mildly Stressing Temperatures
Authors: Mattick Karen L. , Rowbury Robin J. , Humphrey Tom J.
Published: July 2008

Certain rod-shaped bacteria have been reported to form elongated filamentous cells when exposed to marginal growth conditions, including refrigeration temperatures. To expand upon these observations, the filamentation of commensal Escherichia coli, E. coli O157:H7 and Salmonella spp was investigated, following exposure to certain, mildly stressing, levels of temperature, pH or water activity (aw), with levels of cellular protein being monitored during cell elongation, in some experiments. Our studies indicated that cellular filamentation could be demonstrated in all 15 strains of the above organisms tested, following exposure to marginal conditions achieved by incubation at high or low temperatures, high or low pH values and low aw. The level of environmental stress causing filamentation tended to be specific to the particular organisms. For example, Salmonella spp formed filamentous cells at 44°C, whereas E. coli strains, including 0157, grew by binary fission at that temperature, but formed filamentous cells at 46°C. In addition, plate count techniques to enumerate bacteria during filamentation, failed to reflect the increase in cell biomass that was occurring, whereas measurements of protein concentration demonstrated the increase quite strikingly. These findings have important implications for our understanding of the ability of food-borne pathogens to cause disease, since the infectious dose of a microorganism implicated in an outbreak of such disease is typically determined by a viable count method, which could underestimate the number of potential infectious units present in a food that had been stored in such a way as to provide marginal growth conditions.
Applied and Ecological Aspects of Oxidative-Stress Damage to Bacterial Spores and to Oral Microbes
Authors: Marquis Robert E.
Published: July 2008

Bacterial cells have adapted in a variety of ways to resist oxidative stresses and damage in their everyday lives in a predominantly aerobic world. The nearly universal occurrence of resistance mechanisms against oxidative stresses, particularly those due to reactive oxygen species (ROS), suggests that most, if not all, bacteria have to deal with oxidative assaults. A primary source of oxidative stress is aerobic metabolism, which leads to production of ROS such as hydrogen peroxide, superoxide radical, perhydroxyl radical, hydroxyl radical and a variety of other toxic metabolites, including organic peroxides and other organics or inorganics able to transfer electrons to sites of oxidative damage. Anaerobes as well as aerobic and facultative organisms are subject to oxidative stresses, often as a result of their own metabolism of O2 or that of associated facultative organisms. If anaerobes would just ignore oxygen instead of metabolizing it, they would not have to deal with toxic metabolites of their own making. Another major source of oxidative stress comes from the use of oxidative agents in the disinfection-sterilization industry. Notable examples are hypochlorite for water purification and hydrogen peroxide used for industrial sterilization. Antimicrobials such as isoniazide and mitomycin C also act oxidatively to cause damage. In this article, aseptic packaging and processing involving use of hydrogen peroxide for sterilization of packaging materials is reviewed as an example of oxidative stress imposed on bacterial spores and vegetative cells from outside the organisms or the microbial community. The other example considered is related to oral microbiology and infectious disease in which oxidative stress may arise from the metabolism of the oral microbiota or may come from outside through use of oral care products.
The structure of Iranian chemistry research, 1990–2006: An author cocitation analysis
Authors: Osareh Farideh , McCain Katherine W.
Published: July 2008

To study the structure of Iranian chemistry research, we identified 43 Iranian and international chemists who were highly cited in 7,682 Iranian chemistry publications (defined as an article with at least one Iranian author address) indexed in Science Citation Index (SciSearch) between 1990 and 2006, inclusive. We collected cocitation data for these authors from the entire SciSearch file (Dialog, File 34) over the time period. A principal components analysis identified seven interrelated factors accounting for 78% of the variance in the cocitation matrix. Iranian and international authors tended to load on separate factors. Three factors—synthesis of carbonyl compounds, solvent‐free synthesis of organic compounds and oxidation of organic compounds—had an inter‐correlation of | 0.3 | or higher. Physical organic chemistry and ionophores (a mixed factor of Iranian and international authors) connected at a lower value, while crown ethers and analytical chemistry were essentially uncorrelated. The PFNet structure maintained the topical factor groupings and Iranian and international authors tended to appear in separate subnetworks. Geographic and institutional influences, apparently relating in part to institutional affiliation and in part to restricted research topics, appear to underlie the primary structural features of Iranian chemistry in this time period.
High‐Density Gold Nanoparticles Supported on a [Ru(bpy)3]2+‐Doped Silica/Fe3O4 Nanocomposite: Facile Preparation, Magnetically Induced Immobilization, and Applications in ECL Detection
Authors: Guo Shaojun , Li Jing , Wang Erkang
Published: July 2008

A large‐scale process combined sonication with self‐assembly techniques for the preparation of high‐density gold nanoparticles supported on a [Ru(bpy)3]2+‐doped silica/Fe3O4 nanocomposite (GNRSF) is provided. The obtained hybrid nanomaterials containing Fe3O4 spheres have high saturation magnetization, which leads to their effective immobilization on the surface of an ITO electrode through simple manipulation by an external magnetic field (without the need of a special immobilization apparatus). Furthermore, this hybrid nanomaterial film exhibits a good and very stable electrochemiluminescence (ECL) behavior, which gives a linear response for tripropylamine (TPA) concentrations between 5 μM and 0.21 mM, with a detection limit in the micromolar range. The sensitivity of this ECL sensor can be easily controlled by the amount of [Ru(bpy)3]2+ immobilized on the hybrid nanomaterials (that is, varying the amount of [Ru(bpy)3]2+ during GNRSF synthesis).
Reactions at the Ru–S Bonds of Coordinatively Unsaturated Ruthenium Complexes with Tethered 2,6‐Dimesitylphenyl Thiolate
Authors: Ohki Yasuhiro , Takikawa Yuko , Sadohara Hitomi , Kesenheimer Christian , Engendahl Barthel , Kapatina Elissavet , Tatsumi Kazuyuki
Published: July 2008

Coordinatively unsaturated ruthenium complexes with a tethered SDmp (Dmp=2,6‐dimesitylphenyl) ligand, [(DmpS)Ru(PR3)][BArF4] (3 a: R=Et; 3 b: R=Ph; ArF=3,5‐(CF3)2C6H3), were synthesized by the reactions of [{(p‐cymene)RuCl}2(μ‐Cl)2], LiSDmp, phosphines, and NaBArF4. The RuS bonds in 3 a and 3 b were found to serve as the polarized reactive site in reactions with alkyl halides, diazoalkanes, (p‐tosyliminoiodo)benzene, phenylacetylene, and H2. Alkylation of 3 a and 3 b with methyl iodide or ethyl bromide occurred instantaneously to give the thioether complexes [(DmpSR′)RuX(PR3)][BArF4] (4 a: R=Et, R′=Me, X=I; 4 b: R=R′=Et, X=Br; 4 c: R=Ph, R′=Me, X=I; 4 d: R=Ph, R′=Et, X=Br). Treatment of 3 a with diazoalkanes N2CHR (R=CO2Et, SiMe3) led to the cycloaddition of carbenes to the RuS bond to form [DmpS(CHR)Ru(PEt3)][BArF4] (5 a: R=CO2Et; 5 b: R=SiMe3), whereas the reaction with (p‐tosyliminoiodo)benzene gave rise to [DmpS{NS(O)(C6H4‐4‐CH3)O}Ru(PEt3)][BArF4] (6), which contains a five‐membered ruthenacycle of RuSNSO. Addition of phenylacetylene to the RuS bond occurred reversibly to produce the vinyl sulfide complexes [DmpS(PhCCH)Ru(PR3)][BArF4] (7 a: R=Et; 7 b: R=Ph). On the other hand, the phenylacetylene at ruthenium slowly isomerized to vinylidene and bridged Ru and S in the products, [DmpS{C(CHPh)}Ru(PR3)][BArF4] (8 a: R=Et; 8 b: R=Ph). Complex 3 a catalyzed the hydrogenation of acetophenone, in which the heterolytic H–H splitting at the Ru–S site is suggested to be involved in the mechanism.
Penta(pyrenyl)[60]fullerenes: Pyrene–Pyrene and [60]Fullerene–Pyrene Interactions in the Crystal and in Solution
Authors: Matsuo Yutaka , Morita Kouhei , Nakamura Eiichi
Published: July 2008

A new type of fullerene–pyrene hybrid molecule, C60Ar5R [Ar=1‐pyrenyl, 4‐(1‐pyrenyl)C6H4, 4‐{(1‐pyrenyl)CO2}C6H4, and 4‐{(1‐pyrenyl)(CH2)3CO2}C6H4; R=H and Me] was synthesized by a regioselective penta‐addition reaction using organocopper reagents. The compounds were investigated using electrochemical measurements, DFT calculations, single‐crystal X‐ray structural analysis, and spectroscopic and fluorescence measurements. Intramolecular and intermolecular fullerene–pyrene and pyrene–pyrene interactions were characterized in the crystals. Fluorescence measurements in dilute solutions suggested the presence of intramolecular fullerene–pyrene and pyrene–pyrene interactions.
Mitochondrial aspartate/glutamate carrier SLC25A12 gene is associated with autism
Authors: Turunen Joni A. , Rehnström Karola , Kilpinen Helena , Kuokkanen Mikko , Kempas Elli , Ylisaukko‐oja Tero
Published: July 2008

Two single nucleotide polymorphisms (SNP) within Mitochondrial Aspartate/Glutamate Carrier SLC25A12 gene have recently shown to be strongly associated with autism. Here, we attempted to replicate this finding in two separate Finnish samples with autism spectrum disorders. Family‐based association analysis of two SNPs, rs2056202 and rs2292813, previously shown to be associated with autism was performed in two samples with different phenotypic characteristics. The samples included 97 families with strictly defined autism and 29 extended families with Asperger syndrome (AS). We detected association at rs2292813 (FBAT, P=0.0018) in the Finnish autism sample. In, addition other family‐based analysis methods supported this finding. By contrast, analysis of the AS sample yielded no evidence for association. This study shows further support that genetic variants within SLC25A12 gene contribute to the etiology of autism.
A dynamic model for diauxic growth, overflow metabolism, and AI‐2‐mediated cell–cell communication of Salmonella Typhimurium based on systems biology concepts
Authors: Cappuyns Astrid M. , Bernaerts Kristel , Vanderleyden Jos , Van Impe Jan F.
Published: July 2008

The last decades, the research on bacterial cell–cell communication or quorum sensing has been quite intense. Quorum sensing allows bacteria to coordinate their behavior and to act as one entity. Quorum sensing controls microbiological functions of medical, agricultural and industrial importance and a better understanding of the underlying mechanisms and the conditions under which the signaling occurs, offers possibilities for new applications. In this article a dynamic model for diauxic growth, overflow metabolism and AI‐2‐mediated cell–cell communication of Salmonella Typhimurium is presented. The growth, and the production and uptake of the AI‐2 signaling molecule of S. Typhimurium are investigated in a controlled environment (bioreactor). In a first stage a model is developed to describe diauxic growth and overflow metabolism. This model is extended in a second stage to describe AI‐2 dynamics of S. Typhimurium in relation to the growth kinetics and biomass concentration. It is illustrated how this model can be employed to test hypotheses concerning AI‐2 dynamics on the basis of macroscopic data. Biotechnol. Bioeng. 2009;102: 280–293. © 2008 Wiley Periodicals, Inc.
PLS works
Authors: Bro R. , Eldén L.
Published: July 2008

In a recent paper, claims were made that most current implementations of PLS provide wrong and misleading residuals [1]. In this paper the relation between PLS and Lanczos bidiagonalization is described and it is shown that there is a good rationale behind current implementations of PLS. Most importantly, the residuals determined in current implementations of PLS are independent of the scores used for predicting the dependent variable(s). Oppositely, in the newly suggested approach, the residuals are correlated to the scores and hence may be high due to variation that is actually used for predicting. It is concluded that the current practice of calculating residuals be maintained. Copyright © 2008 John Wiley & Sons, Ltd.
Quantification of single‐stranded nucleic acid and oligonucleotide interactions with metal ions by affinity capillary electrophoresis – Part II
Authors: Stettler Alexandra R. , Chaurin Valérie , Constable Edwin C. , Housecroft Catherine E. , Schwarz Maria A.
Published: July 2008

The interactions between tetranucleotides or heptanucleotides and inorganic cations have been measured by affinity CZE. The variation in migration behavior with increasing concentrations of divalent cations (Ca2+, Mg2+ and Ni2+) in the running buffer was investigated and quantified by the calculation of binding constants for mononuclear and multinuclear interactions. In addition to these fundamental studies of binding equilibria, the effect of sequence and the position of the guanine transition metal‐binding site in the oligonucleotide have been investigated.
Pulsatile tinnitus: A harbinger of a greater ill?
Authors: Liess Benjamin D. , Lollar Kevin W. , Christiansen Sidney G. , Vaslow Dale
Published: July 2008

Background.

Pulsatile tinnitus is an uncommon otologic symptom, which may be the presenting complaint of a potentially devastating pathology. Understanding this manifestation as a possible symptom of a significant vascular abnormality is crucial to guide management and treatment.

Methods and Results.

We describe a 38‐year‐old woman with sudden‐onset right‐sided pulsatile tinnitus. A right extracranial internal carotid artery (ICA) dissection was diagnosed with MRI/magnetic resonance angiography (MRA) and treated with anticoagulation. Follow‐up MRI/MRA demonstrated complete resolution. Two months later, left‐sided pulsatile tinnitus evolved. An MRI/MRA of the neck demonstrated left‐sided extracranial ICA dissection. She was treated in a similar fashion and a repeat MRI/MRA demonstrated its resolution.

Conclusion.

Spontaneous extracranial ICA dissection may present with pulsatile tinnitus as the only symptom in 4% to 50% of patients. Subsequent evolution of a contralateral dissection is even more uncommon. Generally, treatment of this phenomenon is conservative utilizing anticoagulation or aspirin; however, surgical intervention may be necessary. © 2008 Wiley Periodicals, Inc. Head Neck 2009
Association between self‐esteem and depression among patients with head and neck cancer: A pilot study
Authors: Kobayashi Mika , Sugimoto Taro , Matsuda Ayako , Matsushima Eisuke , Kishimoto Seiji
Published: July 2008

Background.

We examined the psychological distress in patients with head and neck cancer and investigated how preoperative self‐esteem influenced psychological distress during treatment.

Methods.

Fifty‐eight patients who were scheduled for surgery for head and neck cancer participated. The Japanese version of hospital anxiety and depression scale (HADS) was administered preoperatively, after surgery, and 6 months postoperatively, and Rosenberg self‐esteem scale was administered preoperatively and 6 months postoperatively.

Results.

There were significant differences among the 3 examination periods for psychological distress; the course of anxiety and depression differed between the high self‐esteem group (HSEG) and the low self‐esteem group (LSEG). In all examination periods, anxiety and depression scores for HSEG were significantly better than for LSEG. As for depression, scores did not change significantly over time in HSEG, whereas the scores went from bad to worse in LSEG.

Conclusions.

Patients with cancer undergoing surgery, especially patients with low self‐esteem, need preoperative and ongoing intervention. © 2008 Wiley Periodicals, Inc. Head Neck 2008
Use of Single‐Walled Carbon Nanotubes as Reinforcing Fillers in UV‐Curable Epoxy Systems
Authors: Sangermano Marco , Borella Enrica , Priola Aldo , Messori Massimo , Taurino Rosa , Pötschke Petra
Published: July 2008

CNT were dispersed in an epoxy matrix and cured by means of UV light. An increase on elastic modulus and Tg values was measured by DMTA analysis and attributed to the constraint effect of CNT on polymer chain mobility. Excellent scratch resistant coatings characterized by high critical load, small cracks and high recovery were obtained in the presence of a very low CNT content (0.025 wt.‐%). TEM analysis showed some isolated CNT and some cluster agglomerations of size of about 250 nm. It was shown that it was possible to decrease the surface resistivity of the cured samples by three orders of magnitude in the presence of 0.1 wt.‐% of SWCNT content.

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Extended Chemical CrossLinking of a Thermoplastic Polyimide: Macroscopic and Microscopic Property Development
Authors: Aberg Christopher M. , Ozcam Ali E. , Majikes Jacob M. , Seyam Mohamed A. , Spontak Richard J.
Published: July 2008

Polyimides are well established as gas separation membranes due to their intrinsically low free volume and correspondingly high H2 selectivity relative to other gases such as CO2. Prior studies have established that H2/CO2 selectivity can be improved by crosslinking polyimides with diamines differing in spacer length. In this work, we follow the evolution of macroscopic and microscopic properties of a commercial polyimide over long crosslinking times (tx) with 1,3‐diaminopropane. According to spectroscopic analysis, the crosslinking reaction saturates after ≈24 h, whereas tensile, nanoindentation and stress relaxation tests reveal that the material stiffens, and possesses a long relaxation time that increases with increasing tx. Although differential scanning calorimetry shows that the glass transition temperature decreases systematically with increasing tx, permeation studies indicate that the permeabilities of H2 and CO2 decrease, while the H2/CO2 selectivity increases markedly, with increasing tx. At long tx, the polyimide becomes impermeable to CO2, suggesting that it could be used as a barrier material.

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High Ionic Conductivity of Transparent Film of Hydroxyapatite and Poly(vinyl alcohol) Nanocomposite
Authors: Tajitsu Yoshiro , Fukuda Kazuyuki , Takaki Tosiyuku
Published: July 2008

Summary: Hydroxyapatite (HAp)‐polyvinyl alcohol (PVA) nanocomposite film containing Li+ was designed as a solid polymer electrolyte. A composite was prepared by reacting Ca(OH)2 with H3PO4 in the presence of PVA which is denatured in order to have the carboxyl group, and a LiN(CF3SO2)2 was added. HAp particles were commonly formed in the shape of spindles (long axis ca. 80 nm and short axis ca. 25 nm). The obtained nanocomposite film, in which HAp particles were dispersed uniformly, is transparent, flexible and drawable. Its ionic conductivity is about 10−3 S/m at room temperature. This value is very large. This high ionic conductivity is considerable on the basis of the dynamic percolation theory.
Ambipolar Blends of Cu‐Phthalocyanine and Fullerene: Charge Carrier Mobility, Electronic Structure and their Implications for Solar Cell Applications
Authors: Brütting Wolfgang , Bronner Markus , Götzenbrugger Marcel , Opitz Andreas
Published: July 2008

Summary: Ambipolar transport has been realised in blends of the molecular hole conductor Cu‐phthalocyanine (CuPc) and the electron conducting fullerene C60. Charge carrier mobilities and the occupied electronic levels have been analyzed as a function of the mixing ratio using field‐effect transistor measurements and photoelectron spectroscopy. These results are discussed in the context of photovoltaic cells based on these materials.
New Fluorene‐Based Conjugated Copolymers Bearing Carboxylic Groups
Authors: Kukla Stanislav , Pavlačková Petra , Cimrová Věra , Výprachtický Drahomír
Published: July 2008

Summary: New conjugated copolymers containing 9,9‐dioctylfluorene and terephthalate units (as dimethyl ester or free acid) were synthesized by the Suzuki coupling and characterized by GPC and NMR, FT‐IR and UV‐VIS spectroscopies. These copolymers proved to be good luminescent materials showing emissions in the blue region of the visible spectrum both in solution (λem = 450 nm) and in thin layers. Differences in the luminescence properties were attributed to various extents of aggregation. It was shown that interchain interaction can be avoided by the formation of the copolymer sodium salt. The copolymers were tested as active layers in light‐emitting devices and the formation of their Eu(III) complexes was studied.
Synthesis of Novel Thiophene‐Based Oligomers and Polymers with Thienothiadiazole Units
Authors: Kmínek Ivan , Cimrová Věra , Výprachtický Drahomír , Pavlačková Petra
Published: July 2008

Summary: Novel non‐alkylated and alkylated quinquethiophenes were prepared by the Stille coupling reaction of bis(5‐bromo‐2‐thienyl)thieno[3,4‐c][1,2, 5]thiadiazole (TBr) with 2‐(tributylstannyl)thiophene. These compounds possess long wavelength absorption maxima around 700 nm in solution and 750 nm in thin films. Dibromo compound TBr is further employed as a building block in the syntheses of low‐bandgap copolymers with fluorene units. A soluble alternating copolymer was prepared by the Suzuki coupling of TBr with bis(propane‐1,3‐diyl) 9,9‐bis(2‐ethylhexyl)fluorene‐2,7‐diylbisboro‐nate. It shows the long‐wavelength absorption maximum at 747 nm in solution and at 764 nm in thin film, which indicates extensively conjugated system.
The Experimental Study of Acrylamide Based Photopolymer Recording Materials for Applications in Optical Holography
Authors: Květoň Milan , Havránek Antonín , Fiala Pavel , Richter Ivan
Published: July 2008

Summary: The photopolymer recording material based on acrylamide monomer has been experimentally studied. After illumination with an interference field, the photopolymerization process is initiated and a diffraction grating is formed in real‐time. The performance of the material depends on its chemical composition and recording parameters. Due to its self‐developing characteristics, the real‐time measurement of hologram formation is used for detection of the recording process. From the measurement, properties of the material can be determined and optimized for different holographic applications.
Estrogen and its receptors in cancer
Authors: Chen George G , Zeng Qiang , Tse Gary MK
Published: July 2008

The involvement of estrogen and its receptors in the development of cancer has been known for years. However, the exact mechanism responsible is far from clear. The estrogen‐mediated carcinogenic process is complicated by recent findings, which reveal that estrogens have multiple functions in cells, which can be either adverse or beneficial, and that the effects of estrogen may be cell‐type or organ dependent. The estrogenic effect may be also greatly influenced by the state of two estrogen receptors, ERα and ERβ. This review will discuss the role and function of estrogens and its receptors in cancers of three categories: (1) Breast cancer and gynecologic cancers, (2) Cancers of endocrine organs, (3) Lung cancer and cancers of digestive system. We will also review some novel treatments aiming to interfere with relevant pathways mediated by estrogens and its receptors. © 2008 Wiley Periodicals, Inc. Med Res Rev, 28, No. 6, 954–974, 2008
Fundamental Molecular Weight Distribution of RAFT Polymers
Authors: Tobita Hidetaka
Published: July 2008

The molecular weight distribution formed in an ideal reversible addition‐fragmentation chain transfer (RAFT)‐mediated radical polymerization is considered theoretically. In this polymerization, the addition to the RAFT agent is reversible, and the active period on the same chain could be repeated, via the two‐armed intermediate, with probability 1/2. This possible repetition is accounted for by introducing a new concept, the overall active/dormant periods. With this method, the apparent functional form of the molecular weight distribution (MWD) reduces to that proposed for the ideal living radical polymers (Tobita, Macromol. Theory Simul. 2006, 15, 12). The repetition results in a broader MWD than without the repetition. The formulae for the average molecular weights formed in batch and a continuous stirred tank reactor are also presented.

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Neuroleukemiosis: Case report of leukemic nerve infiltration in acute lymphoblastic leukemia
Authors: Aregawi Dawit G. , Sherman Jonathan H. , Douvas Michael G. , Burns Ted M. , Schiff David
Published: July 2008

We describe a patient in remission from acute lymphoblastic leukemia who developed a painless common peroneal neuropathy. Magnetic resonance imaging (MRI) revealed nerve thickening and enhancement, while a positron emission tomography (PET) scan demonstrated increased fluorodeoxyglucose uptake in a large segment of the neurovascular bundle, suggesting peripheral nerve infiltration. Both findings resolved following treatment with chemotherapy that crossed the blood–nerve barrier. In selected patients presenting with peripheral neuropathy, MRI and PET scan can be helpful in the diagnosis of peripheral nerve infiltration. Muscle Nerve, 2008
On the Correlation between Miscibility and Solubility Properties of Energetic Plasticizers/Polymer Blends: Modeling and Simulation Studies
Authors: Abou‐Rachid Hakima , Lussier Louis‐Simon , Ringuette Sophie , Lafleur‐Lambert Xavier , Jaidann Mounir , Brisson Josée
Published: July 2008

In this paper, systems for which miscibility (hydroxyl‐terminated polybutadiene–dioctyl adipate or HTPB–DOA) or immiscibility (HTPB–diethylene glycol dinitrate or HTPB–DEGDN) have been firmly established were used to test the usefulness of an atomistic molecular mechanics model. Two specific aspects were discussed: miscibility assessment of a plasticizer/polymer blend, and predictions of the enthalpy of vaporization. Simulations were carried out using Amorphous Cell and Discover packages of the Material Studio software using Compass force field for all calculations. A good agreement has been found for miscibility observations of blends, and for solubility parameter, density, and derived enthalpy of vaporization for pure substances. Therefore, the approach proposed in this work is a useful tool to provide insights on miscibility and properties of a given polymer/plasticizer blend. In addition, it is a promising technique to help in screening among several plastic bonded explosive (PBX) formulations prior to real experimental tests.
Conformational studies of [Abu3, 11]‐SFTI‐1, an analogue of the trypsin inhibitor isolated from sunflower seeds
Authors: Brzozowski Krzysztof , Majewski Radosław , Jaśkiewicz Anna , Łȩgowska Anna , Klaudel Lidia , Rodziewicz‐Motowidło Sylwia , Rolka Krzysztof
Published: July 2008

With only 14 amino acid residues, the trypsin inhibitor SFTI‐1 is the smallest naturally occurring serine proteinase inhibitor. It consists of two cyclic fragments (with head‐to‐tail cyclization and a disulfide bridge). In our previous paper, we showed that the removal of the disulfide bridge produced 2.4‐fold lower activity. Here, we present the total conformational analysis of the [Abu3, 11]‐SFTI‐1 analog by means of 2D NMR spectroscopy in conjunction with theoretical methods. The peptide was synthesized by Fmoc SPPS. It was cyclized with PyBop and DIPEA in DMF. The NMR studies were performed in DMSO‐d6 at 303 K. Conformations of the peptide studied were calculated by the following three approaches: distance geometry (DG), molecular dynamics (MD) and determination of the statistical weights of conformations. The first two algorithms use a CHARMM force field, whereas the last uses an ECEPP/3 force field. Our calculations resulted in three sets of conformers with 7, 9 and 6 representatives, respectively. All our results were compared with published ones. It was found that the peptide has an ill‐defined structure. Despite its conformational flexibility, the binding loop (3–11 fragment) displayed geometry similar to the corresponding fragments of the other SFTI‐1 analogs and to the inhibitor itself. Furthermore, the peptide bond between the Ile7 and Pro8 residues adopts cis geometry, which is essential for inhibitory activity. Copyright © 2008 European Peptide Society and John Wiley & Sons, Ltd.
Preparation of p‐type transparent conducting tin–antimony oxide thin films by DC reactive magnetron sputtering
Authors: Ji Zhenguo , Xi Junhua , Huo Lijuan , Zhao Yi
Published: July 2008

P‐type transparent conducting tin–antimony oxide (TAO) films were successfully prepared by DC reactive magnetron sputtering followed by post annealing in the air. Structural, optical and electrical properties of the TAO films were investigated. X‐ray diffraction studies showed that the films are polycrystalline with orthorhombic structure of Sb2O4. UV–Visible absorption and transmittance spectra showed that the optical band‐gap of the TAO films is about 3.90 eV, and the overall transmittance is higher than 85% in the visible region. Hall effect measurement indicated that the Sn/Sb ratio is a critical parameter to get p‐type conducting TAO films. It was found that 0.19 < Sn/Sb ratio < 0.43 is the range in which p‐type TAO films could be obtained. Hole concentration as high as 4.03 × 1019 cm–3 and electrical resistivity as low as 0.155 Ωcm were achieved, showing potential applications of TAO films as p‐type transparent conducting films. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Bivariate modeling of interobserver agreement coefficients
Authors: Shoukri Mohamed M. , Donner Allan
Published: July 2008

Many studies of interobserver agreement yield outcome measures on more than one binary trait. For example, Becker et al. (Int. J. Psychiatry Med. 2002; 32(3):271–283) reported on a study of depression and anxiety as two outcome measures obtained on 173 patients evaluated by two screening instruments, the first using a Patient Health Questionnaire and the second employing a Structured Clinical Interview. In this case, although inferences on each trait separately are usually of main interest, a question that also arises is whether or not the level of interobserver agreement can be regarded as stable across the two traits. In this paper, we develop the required methodology and provide an illustrative example. Copyright © 2008 John Wiley & Sons, Ltd.
The Late Cenozoic of northern Transbaikalia and paleoclimates of southern East Siberia
Authors: Enikeev F.I.
Published: July 2008

Comprehensive studies have been applied to a core from well 126 in the Chara basin (eastern Baikal-Stanovoy upland). The 1180 m thick drilled section comprises Upper Pleistocene sediments (0–173.1 m) with two intervals of varved silt coeval with the Wurm Glacial, two Middle Pleistocene glacial intervals at 180–263.5 m and 337–424.7 m, earliest Pleistocene (424.7–550 m), Pliocene (550–1036 m), and Miocene (1036–1180 m) strata. The core records the history of Late Cenozoic climate and vegetation for the past 20 Myr (with two large gaps), which has been reconstructed using the pollen analysis. Interpolation of long- and medium-period climate oscillations tied to the time scale allows predicting a trend of possible climate change for the future 2–2.5 kyr.
Petrology of the Early Mesozoic ultramafic-mafic Luchina massif (southeastern periphery of the Siberian craton)
Authors: Buchko I.V. , Sorokin A.A. , Izokh A.E. , Larin A.M. , Kotov A.B. , Sal’nikova E.B. , Velikoslavinskii S.D. , Sorokin A.P. , Yakovleva S.Z. , Plotkina Yu.V.
Published: July 2008

Three zones of layered series — lower, middle, and upper — composed of dunites and plagiodunites, troctolites and olivine gabbros, gabbros and gabbronorites, respectively, have been recognized in the Luchina massif. The melt that produced the massif rocks was of picrite-basaltic composition (15–16% MgO), and its crystallization took place at 1300–1000 °C and ∼7 kbar. The Early Mesozoic age (248±1 Ma), geochemistry, and location of the massif on the northern periphery of the eastern segment of the Mongolo-Okhotsk fold belt suggest that it formed either in the hinterland of subduction zone dipping beneath the southern margin of the Dzhugdzhur-Stanovoy superterrane or on the periphery of the Siberian superplume during the mantle heating.
Numerical solution of Maxwell’s equations for anisotropic media using the Laguerre transform
Authors: Mastryukov A.F. , Mikhailenko B.G.
Published: July 2008

We apply the spectral Laguerre transform in the time domain to solve 2D Maxwell’s equations for propagation of electromagnetic waves in lossy anisotropic media. The new algorithm is simple and efficient as Maxwell’s equations are reduced to a harmonic series of linear algebraic equations where the matrix is independent of the harmonic order and is the same for all harmonics.

The efficiency of the algorithm is improved by fitting a specially introduced free parameter of the Laguerre transform. If it is large, the solution spectrum shifts toward higher harmonics which is formally equivalent to the case of ray approximation.

The Laguerre solution is comparable with high-order accurate finite-difference time-domain (FDTD) solutions. The method is stable both in the region of the wavefield, where conductivity approaches zero and the spectral Fourier method is unstable, and in the high-conductivity region, where the explicit FDTD code requires a too small time step.
Comparison of the effects of a high- and normal-casein breakfast on satiety, ‘satiety’ hormones, plasma amino acids and subsequent energy intake
Authors: Veldhorst Margriet A. B. , Nieuwenhuizen Arie G. , Hochstenbach-Waelen Ananda , Westerterp Klaas R. , Engelen Marielle P. K. J. , Brummer Robert-Jan M. , Deutz Nicolaas E. P. , Westerterp-Plantenga Margriet S.
Published: July 2008

The present study compared the effects of a high- and normal-casein-protein breakfast on satiety, ‘satiety’ hormones, plasma amino acid responses and subsequent energy intake. Twenty-five healthy subjects (BMI 23·9 (sem 0·3) kg/m2; age 22 (sem 1) years) received a subject-specific standardised breakfast (20 % of daily energy requirements): a custard with casein as the single protein source with either 10, 55 and 35 (normal-casein breakfast) or 25, 55 and 20 (high-casein breakfast) % of energy (En%) from protein, carbohydrate and fat respectively in a randomised, single-blind design. Appetite profile (visual analogue scale; VAS), plasma glucose, insulin, glucagon-like peptide 1, ghrelin and amino acid concentrations were determined for 4 h; here the sensitive moment in time for lunch was determined. Subjects came for a second set of experiments and received the same custards for breakfast, and an ad libitum lunch was offered at 180 min after breakfast; energy intake was assessed. There were increased scores of fullness and satiety after the 25 En% casein-custard compared with the 10 En% casein-custard, particularly at 180 min (26 (sem 4) v. 11 (sem 5) mm VAS; P < 0·01) and 240 min (13 (sem 5) v. − 1 (sem 5) mm VAS; P < 0·01). This coincided with prolonged elevated plasma amino acid concentrations; total amino acids and branched-chain amino acids were higher after the 25 En% casein-custard compared with the 10 En% casein-custard at 180 and 240 min (P < 0·001). There was no difference in energy intake (3080 (sem 229) v. 3133 (sem 226) kJ for 25 En% and 10 En% respectively; NS) from the ad libitum lunch. In conclusion, a breakfast with 25 % of energy from casein is rated as being more satiating than a breakfast with 10 % of energy from casein at 3 and 4 h after breakfast, coinciding with prolonged elevated concentrations of plasma amino acids, but does not reduce subsequent energy intake.
Alfvén eigenmodes in magnetic X-point configurations with strong longitudinal fields
Authors: AYED N. BEN , McCLEMENTS K. G. , THYAGARAJA A.
Published: July 2008

A perturbative three-dimensional analysis is presented of Alfvén waves in a magnetic X-point configuration with a strong longitudinal guide field. The waves are assumed to propagate in the direction of the X-line, and both the plasma beta and equilibrium plasma current are taken to be zero. This provides a simple model of Alfvén wave propagation in the divertor region of tokamak plasmas. It is shown that the presence of the X-point places constraints on the structure of the leading-order (shear Alfvén) eigenfunctions. These eigenfunctions, and fast wave corrections to them, are determined explicitly for two cases. In the first of these the stream function for the shear Alfvén flow is azimuthally symmetric in the X-point plane and singular at the X-line; in the second case the stream function is largely confined to two quadrants in the X-point plane and is non-singular. For the latter scenario it is shown that coupling of the shear and fast waves is strongly localized to the vicinity of the separatrix.