bluuebunny/crossref_metadata_2025 huggingface dataset:
Chromate reducing and plant growth promoting activies of psychrotrophic Rhodococcus erythropolis MtCC 7905
Authors: Trivedi Pankaj , Pandey Anita , Sa Tongmin
Published: December 2007

A psychrotrophic bacterial strain resistant to 300 mg l–1 of Cr6+ was isolated from metal contaminated soil samples from a site situated in the Indian Himalayan Region. Based on 16 S rRNA analysis the isolate showed maximum similarity to Rhodococcus erythropolis. Rhodococcus erythropolis MTCC 7905 reduced substantial amounts of Cr6+ to Cr3+ at 10 °C and showed plant growth promotion. The isolate offer promise as inoculant to promote plant growth of pea (Pisum sativum) in the presence of toxic Cr6+ concentration. To the best of our knowledge this is the first report on a psychrotrophic strain belonging to species R. erythropolis and its functional characterization to reduce Cr6+ and promote plant growth at low temperature. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Roles of larger conductance mechanosensitive channels (MscL) in sporulation and Act secretion in Streptomyces coelicolor
Authors: Wang Chun‐Xia , Ge Huan‐Xi , Hou Xiao‐Ping , Li Yong‐Quan
Published: December 2007

Larger conductance mechanosensitive channels (MscL) is a conserved channel existing in eukarya, bacteria and archaea. The gene SCO3190 in Streptomyces coelicolor encodes an MscL homolog of Escherichia coli. To elucidate the physiological roles of MscL in S. coelicolor (Sc‐MscL), deletion mutant was constructed. The Sc‐MscL deletion brought sporulation ahead, and had no significant influence to antibiotic synthesis in S. coelicolor. When Sc‐MscL was overexpressed in S. coelicolor, the colony of S. coelicolor was small and sleek with abundant blue pigment corresponding to actinorhodin (Act). Furthermore, abundant blue pigment displayed on hypoosmotic LB plates comparing to hyperosmotic R5 plates. These results suggested that Sc‐MscL was involved into Act secretion and sporulation relating to osmotic stress response in S. coelicolor. Moreover, Sc‐MscL showed possible functional pentamer by cross‐linking in vitro. It is first report about biochemical and functional characterization of MscL in S. coelicolor. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Temperature and pH effect on lindane removal by Streptomyces sp. M7 in soil extract
Authors: Benimeli C. S. , González A. J. , Chaile A. P. , Amoroso M. J.
Published: December 2007

This work was conduced to study the removal of γ‐hexachlorocyclohexane (lindane) in a soil extract liquid medium (SE) by Streptomyces sp. M7 and to determine the influence of pH and temperature on bacterial growth and pesticide removal in this medium. When Streptomyces sp. M7 was cultured in SE supplemented with lindane 100 μg l–1 at different initial pH, the maximum growth was observed at pH 7 and the microorganism was not able to grow at pH 5 and 9; the highest pesticide removal (70.4%) by Streptomyces sp. M7 was noted at an initial pH of 7 at 4 weeks of incubation. The maximum removal (70% approximately) was observed when the microorganism was incubated in SE at 30 °C; although the optimal temperature for Streptomyces sp. M7 growth, with and without lindane, was 25 °C, and for the pesticide removal was 30 °C. The results of this study suggest that this actinomycete strain appears as an effective alternative in the remediation of lindane polluted sites. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Microbial diversity analysis of former salterns in southern Taiwan by 16S rRNA‐based methods
Authors: Wang Chung‐Yi , Ng Chang‐Chai , Chen Tseng‐Wei , Wu Sz‐Jie , Shyu Yuan‐Tay
Published: December 2007

The microbiota diversity of the former salterns in southern Taiwan was investigated by denaturing gradient gel electrophoresis (DGGE) and fluorescence in situ hybridization (FISH). Soil samples from three salterns were analyzed using DGGE and 16S rRNA from 502 colonies representing 5 archaea and 18 bacteria taxonomic groups. Each representative taxonomic group was further identified, whereas 8.7% of clones were unclassified microorganisms. Chromohalobacter, Halomonas and Virgibacillus are dominant in the Biemen saltern, Chiguensis saltern and Szutsau saltern, respectively. During FISH analysis, several taxonomic‐specific probes were used. The DAPI‐stained‐cell count in the Szutsao saltern had a higher number of microorganisms (4.58 × 107 cell/cm3) than the other salterns. Archaea occupied 2.7–6.6% whereas bacteria accounted for 37.2–52.9% of total microbial population at the three sites. Among these three sampling sites, the Szutsao saltern had the highest diversity in halophilic microbial composition, as indicated by DGGE and FISH. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Biosorption of metal and salt tolerant microbial isolates from a former uranium mining area. Their impact on changes in rare earth element patterns in acid mine drainage
Authors: Haferburg Götz , Merten Dirk , Büchel Georg , Kothe Erika
Published: December 2007

The concentration of metals in microbial habitats influenced by mining operations can reach enormous values. Worldwide, much emphasis is placed on the research of resistance and biosorptive capacities of microorganisms suitable for bioremediation purposes. Using a collection of isolates from a former uranium mining area in Eastern Thuringia, Germany, this study presents three Gram‐positive bacterial strains with distinct metal tolerances. These strains were identified as members of the genera Bacillus, Micrococcus and Streptomyces. Acid mine drainage (AMD) originating from the same mining area is characterized by high metal concentrations of a broad range of elements and a very low pH. AMD was analyzed and used as incubation solution. The sorption of rare earth elements (REE), aluminum, cobalt, copper, manganese, nickel, strontium, and uranium through selected strains was studied during a time course of four weeks. Biosorption was investigated after one hour, one week and four weeks by analyzing the concentrations of metals in supernatant and biomass. Additionally, dead biomass was investigated after four weeks of incubation. The maximum of metal removal was reached after one week. Up to 80% of both Al and Cu, and more than 60% of U was shown to be removed from the solution. High concentrations of metals could be bound to the biomass, as for example 2.2 mg/g U. The strains could survive four weeks of incubation. Distinct and different patterns of rare earth elements of the inoculated and non‐inoculated AMD water were observed. Changes in REE patterns hint at different binding types of heavy metals regarding incubation time and metabolic activity of the cells. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Microbes and metals: interactions in the environment
Authors: Haferburg Götz , Kothe Erika
Published: December 2007

Research on the behaviour of microorganisms in geogenic or anthropogenic metallomorphic environments is an integral part of geomicrobiology. The investigation of microbial impact on the fate of minerals and geologically significant compounds of mining areas can lead to an understanding of biogeochemical cycles. Metabolic processes of microorganisms are the cause for the dissolution of minerals, and especially pyrite oxidation results in the generation of acid mine drainage which, in turn, leads to heavy metal contamination as a result of mining activities. On the other hand, microbial metabolism can also contribute to the formation of certain ore deposits over geological time.

The adaptation to heavy metal rich environments is resulting in microorgansims which show activities for biosorption, bioprecipitation, extracellular sequestration, transport mechanisms, and/or chelation. Such resistance mechanisms are the basis for the use of microorganisms in bioremediation approaches. As only a small part of the worldwide occurring prokaryotes has been described yet, the understanding of the role bacteria play in a geogenic and pedogenic context is very likely to change deeply as soon as more habitat relevant microbial functions can be described. Examples for the identification of microbial processes from case studies may help to advance this field. The strongly interdisciplinary field of bio‐geo‐interactions spanning from the microorganism to the mineral holds much promise for future developments in both basic research as well as applied sciences. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Hydrocarbon degradation by thermophilic Nocardia otitidiscaviarum strain TSH1: physiological aspects
Authors: Zeinali Majid , Vossoughi Manouchehr , Ardestani Sussan K. , Babanezhad Esmaeil , Masoumian Mohamadreza
Published: December 2007

Indigenous thermophilic hydrocarbon degraders are of special significance for the bioremediation of oil‐contaminated desert soils with ambient temperature of 45–50 °C. The first objective of this study was to demonstrate the hydrocarbon‐degrading capability of Nocardia otitidiscaviarum TSH1 (DSM 45036) which grows optimally at 50 °C. Analysis of the metabolic profile of the strain TSH1 showed that it could metabolize phenol, intermediate‐chain‐length n ‐alkanes and some polycyclic aromatic hydrocarbons (PAHs) ranging in size from two to four fused rings efficiently, but not toluene and xylene. N. otitidiscaviarum TSH1 was able to survive and grow at phenol concentrations up to 875 mg l–1. For the first time, the physiological response of a thermophilic Nocardia strain to poorly available hydrophobic compounds was also investigated. When grown on a mineral salt medium with hexadecane, N. otitidiscaviarum TSH1 showed very high affinity for the organic phase. Additionally, PAH‐grown cells were considerably hydrophobic. The capacity of PAH‐utilizing N. otitidiscaviarum TSH1 isolate to produce biosurfactants was also investigated. Fatty acids (C14–C18) were detected by GC‐MS analysis during bacterial growth in PAH supplemented mineral media. High cell surface hydrophobicity and capability of N. otitidiscaviarum TSH1 to degrade different hydrocarbons at 50 °C may make it an ideal candidate to treat oil‐contaminated desert soils. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Beating in free polarization decay
Authors: Gol'dort V G , Ledovskikh D V , Khvorostov E B , Rubtsova N N
Published: December 2007

Free polarization decay formed by Stark switching technique in a presence of 9P(32) CO2 laser low intensity radiation in a low pressure gas 13CH3F is investigated as a function of Stark field strength. Rotation transition R(4,3) of vibrational mode 0 ↔ 1 ν3 was used. The beatings between free polarization signals originating from transitions with different magnetic quantum numbers appeared as periodic peaks with the period inversely proportional to the Stark field strength. The weighted difference between permanent dipole moments of upper and lower vibration states is estimated from these data, in agreement with known values of permanent dipole moments.
Temperature‐dependent magneto‐photoluminescence spectroscopy of carbon nanotubes: evidence for dark excitons
Authors: Shaver J. , Kono J.
Published: December 2007

We review recent experimental and theoretical studies on the radiative properties of excitons in single‐walled carbon nanotubes (SWNTs) as a function of magnetic field and temperature. These studies not only provide new insight into the fundamental properties of excitons in the ultimate one‐dimensional (1D) limit but also reveal new phenomena associated with the unique crystal and electronic structure of SWNTs. During the past several years, SWNTs have emerged as one of the most ideal systems available for the systematic study of 1D excitons, which are predicted to possess a set of properties that are distinctly different from excitons in higher dimensions. In addition, their tubular nature allows them to exhibit non‐intuitive quantum phenomena when subjected to a parallel magnetic field, which breaks time reversal symmetry and adds an Aharonov‐Bohm phase to the electronic wavefunction. In particular, a series of recent experiments demonstrate that such a symmetry‐breaking magnetic field can dramatically “brighten” an optically‐inactive, or dark, exciton state at low temperature (see the title figure on the right). We show that this phenomenon, magnetic brightening, can be understood as a consequence of interplay between the strong intervalley Coulomb mixing and field‐induced lifting of valley degeneracy. Detailed temperature‐dependent photoluminescence studies of excitons in SWNTs in a varying magnetic field have thus provided one of the most critical tests for recently proposed theories of 1D excitons taking into account the strong 1D Coulomb interactions and unique band structure on an equal footing. Furthermore, results of these studies suggest the intriguing possibility of manipulating the optical properties of SWNTs by judicious symmetry control, which can lead to novel devices and applications in lasers and optoelectronics.
Composite Nano‐Titanium Oxide–Chitosan Artificial Skin Exhibits Strong Wound‐Healing Effect—An Approach with Anti‐Inflammatory and Bactericidal Kinetics
Authors: Peng Chiung‐Chi , Yang Ming‐Hua , Chiu Wen‐Ta , Chiu Chun‐Hung , Yang Chi‐Shen , Chen Yi‐Wen , Chen Kuan‐Chou , Peng Robert Y.
Published: December 2007

A composite nano‐TiO2–chitosan with collagen artificial skin (NTCAS) showed promising characteristics of moderate water absorptivity (110 wt.‐%), fine thickness (0.34 mm), low density (0.33 mg · mm−3), moderate biodegradability (<3.0%), and favorable time‐dependent biodegradability (0.0521 mg · mL−1 · h−1 on Day 0; 0.0006 mg · mL−1 · h−1on Day 3 post covering). More importantly, it showed uniquely potent bactericidal (sterilization) property with relatively large values of pseudo first‐order kinetic coefficients (0.1736–0.0360 min−1) for TiO2 contents ranging from 2.63 × 10−5 to 2.11 × 10−4 mg · cm−2. In wounded subjects, NTCAS showed a steady level of TNF‐α, while the IL‐6 level reached a peak on Day 7, although significantly lower than in the control and Duoderm groups. In the animal model, NTCAS showed better and faster recovery than the other groups, which can be attributed to the unique bactericidal effect of nano‐TiO2 and immune‐enhancing effect of chitosan. NTCAS is a promising artificial skin substitute and is superior to any other market product currently in use.

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Morphology and Phase Separation of Hydrophobic Clusters of Soy Globular Protein Polymers
Authors: Sun Xiuzhi Susan , Wang Donghai , Zhang Lu , Mo Xiaoqun , Zhu Li , Bolye Dan
Published: December 2007

Protein hydrophobic interaction has been considered the most important factor dominating protein folding, aggregation, gelling, self‐assembly, adhesion, and cohesion properties. In this paper, morphology and phase separation of hydrophobic clusters, networks, and aggregates of soy globular protein polymers, induced by using a reducing agent (NaHSO3), are studied using microscopic instruments. The morphology and phase separation of these hydrophobic clusters are sensitive to protein structure and composition, pH, and ionic‐strength (Im). Most of the clusters are in spherical‐shape architecture and mainly consist of hydrophobic polypeptides. Rod‐shape clusters were also observed at higher ionic strength, and mainly consist of hydrophilic polypeptides. The ratio of hydrophobic/hydrophilic (HB/HL) polypeptides is important to facilitate the formation of clusters in an environment with a certain pH value and ionic strength. At HB/HL 0.8, uniform spherical clusters were observed and diameters ranged from 30 to 70 nm. At HB/HL <0.8, large spherical clusters were formed with diameters ranging from 100 to 1 000 nm, and at HB/HL ≥1.8, large hydrophobic aggregates formed, and size of aggregates can be up to 2 500 nm. When solid content increased from 3% to 38%, at Im ≤ 0.058 mol · L−1, pH = 4.8, HB/HL ratio <0.8, the networks turned into a continuous substance that has strong adhesion to various surfaces; at Im ≥ 0.115 mol · L−1, HB/HL ratio ≥1.8, the large aggregates became very cohesive and viscoelastic. Clear phase separation was observed during curing between hydrophobic and hydrophilic protein polymers. Phase‐separation degree increased as HB/HL ratio increased.

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Are quantitative measurements by electrochemical diagnostic procedures possible?
Authors: Finke M.
Published: December 2007

In order to guarantee the demanded run‐time of chemical and petrochemical production plants and to keep them in up most technical conditions, an alignment between maintenance strategy, inspection intervals, and diagnostic methods is necessary. For the determination of the useful life of an equipment, it is necessary to select testing methods, which possess high sensitivity and long PF intervals (lead time to failure). This approach supports an optimal condition‐based maintenance program to avoid unplanned shutdown. In order to monitor corrosion processes, electrochemical methods can be successfully employed. In this paper, contributions of some online diagnostic methods are described, especially concerning their quantitative presentation.
Listen to corrosion at work — A newly developed versatile corrosion monitoring tool ready for plant application
Authors: Schmitt G.
Published: December 2007

The basic principle of a new approach of electrochemical noise (ECN) diagnostics, the Coulombs counting method, is outlined, and the wide range of application as an online‐monitoring tool in technical corrosion systems is exemplified. It is shown that corrosion monitoring can be achieved with ECN sensors as simple as monitoring temperatures. A special feature of this method is that corrosion in crevices or under deposits can be investigated under real‐time conditions. This allows to monitor the efficiency of mitigation measures, e.g. application of corrosion inhibitors, under crevice corrosion conditions. The new ECN diagnostic approach listens to the message of corroding systems and translates it into technically relevant information.
Using electrochemical noise for corrosion testing: Determination of critical pitting temperatures
Authors: Heyn A. , Goellner J.
Published: December 2007

The phenomenon of the electrochemical noise is already known for some decades. With the growing technical possibilities in the fields of electronic measuring devices and recording techniques, a new window of observation has been opened to observe and record smallest charge fluctuations from dynamic corrosion processes. The main advantage compared to other electrochemical techniques is the contemporary and sensible way of getting information from the beginning of and the tendency to corrosion. This is also the basis for applications for corrosion testing and examination. In this paper, it is shown in the example of the determination of critical pitting temperatures (CPTs), how a conventional testing method can be improved by these advantages. The prerequisites concerning the measuring technique, the experimental procedure and the assessment of the measured data are shown as well as some fundamental and technical restrictions, which have to be taken into account.
An attempt to detect SCC by combined measurements of electrochemical noise and acoustic emission
Authors: Kovač J. , Leban M. , Legat A.
Published: December 2007

Electrochemical voltage and current noise (EN) were measured simultaneously with acoustic emission (AE) during intergranular stress‐corrosion cracking (IGSCC) on tensile specimens under a constant load. The elongation of the test specimens was also measured continuously during the tests, as an additional measuring technique. The test specimens were made from sensitized stainless steel of type 304, and immersed in an aqueous solution of sodium thiosulphate. The main aim of our work was to find out how successfully IGSCC processes could be detected by the simultaneous use of all three measurement methods. The results of the tests indicated that the accumulation of cracking and dissolution events could be satisfactorily monitored, whereas it was not possible to detect individual IGSCC events with the existing measuring set‐up. It is not clear whether this inability to detect single IGSCC events was a consequence of the continuous nature of the IGSCC processes, or whether it was due to the insufficient resolution of the measurement system set‐up.
Corrosion and corrosion testing of magnesium alloys
Authors: Bender S. , Goellner J. , Heyn A. , Boese E.
Published: December 2007

The corrosion behaviour of magnesium alloys is not substantially comparable to other metals, such as iron, nickel and copper. It is always accompanied by hydrogen evolution. More hydrogen is evolved at a more positive potential or a higher anodic current density. The ‘strange’ hydrogen evolution behaviour is a common phenomenon for magnesium alloys and it is called negative difference effect (NDE). The NDE continues to receive considerable discussion.

Furthermore, the corrosion behaviour of magnesium alloys depends mainly on the pH value of the surrounding electrolyte. Voluminous reaction products, formed in neutral electrolytes, lead to a diffusion‐controlled dissolution on the surface of the underlying magnesium alloy. Therefore, influences from structure and alloying are suppressed very strongly. In alkaline environments, passivation occurs as a result of the formation of a hydroxide layer on the magnesium surface. Therefore, differences in the corrosion behaviour between the alloys are hardly detectable. Measurable effects can only be detected using very ‘aggressive’ corrosion conditions. Present methods do not adequately take into account the specific character of the corrosion of magnesium alloys. It can be better characterized using a rotating disc electrode for electrochemical measurements, which enables model defined flow conditions on the surface. Furthermore, the application of electrochemical noise offers the possibility of a simple and sensitive assessment of the corrosion susceptibility of magnesium alloys. Due to the high sensitivity of this measurement procedure, it is also possible to carry out examinations under more practical conditions.
Investigation of the initial stage of crevice corrosion on Al99.5 by electrochemical noise analysis
Authors: Schneider M. , Galle K.
Published: December 2007

The electrochemical noise analysis (ENA) is a powerful tool to investigate the initial state of local corrosion processes as pitting corrosion or crevice corrosion on aluminium alloys. The focus of this work lays on Al99.5 (AA1050). In spite of the good corrosion protection and the very low passive current density the noise activity in the early state of corrosion can be very well observed. ENA was performed by using current noise measurement under potentiostatic control. The effect of chromate inhibitors on the noise activity of the initial state of corrosion on Al99.5 is surprisingly negligible. This phenomenon is discussed in this paper.
Modeling of electrochemical noise transients
Authors: Bierwirth M. , Goellner J.
Published: December 2007

Starting from the elementary corrosion reactions on a passive metal surface a model is developed for the origin of electrochemical noise. The ion currents flowing at the electrochemical reactions are described by the electrons remaining in the metal and then interpreted as a measuring signal. The measurable sum current is composed of the superimposition of the electron currents of the partial reactions. Due to the inhomogeneity of the metal surface, local metal dissolutions take place in preferential areas until the area is consumed or repassivated after short times. The short‐time surplus of free electrons leads for every metal dissolution event to a current transient, which itself consists of the partial currents of the elementary anodic and cathodic reactions. Due to the different reaction speeds, there are temporary charge disequilibria and thus measurable noise transients. In model calculations the influence of the diffusion of the oxygen on the sum signal as well as the variation of the anodic current is shown. Furthermore, the results show that a measurable noise signal can only arise under certain conditions. This signal arisen directly at the metal surface is not, however, ascertainable without further amplification. In the measurement amplifiers filter stages play an important role for signal conditioning. The influence of the measuring technique is shown at the filtration of a simulated test signal in different frequency domains. It is discussed how the signal distortion affects the detectability of the partial reactions described at the beginning and in which way the noise signal is estimated. Indications for the layout of suitable measuring parameters are given.
Copolymers of Thiophene and Cyano‐Substituted Phenylene: Facile Tuning of Electronic Energy Levels and their Photovoltaic Application
Authors: Zou Yingping , Sang Guangyi , Zhou Erjun , Li Yongfang
Published: December 2007

A series of copolymers of thiophene and different molar ratios of DOCNP have been synthesized and characterized. The copolymers exhibit interesting tunable electronic energy levels and optoelectronic properties. The LUMO energy levels of the copolymers decreased with increasing DOCNP content, while the HOMO levels changed only a little. The copolymer films show broad absorption and high absorption coefficients in the visible region, which could be beneficial to the application as photovoltaic materials in solar cells. The results show that the introduction of a proper amount of electron‐acceptor groups in the polymer main chains induces an extension of the absorption spectra and improves the photovoltaic properties of the copolymers.

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Solid‐State Electrochromic Devices via Ionic Self‐Assembled Multilayers (ISAM) of a Polyviologen
Authors: Jain Vaibhav , Yochum Hank , Wang Hong , Montazami Reza , Hurtado Mónica A. Vidales , Mendoza‐Galván Arturo , Gibson Harry W. , Heflin James R.
Published: December 2007

A PV was synthesized by polymerization of N,N′‐bis(δ‐aminopropyl)‐4,4′‐bipyridinium bromide hydrobromide (APD) and isophthaloyl chloride (ISP). The PV was completely soluble in water as well as in organic solvents. The spectroelectrochemical and EC properties of the resulting ionic self‐assembled multilayers of PV/poly‐(2‐acrylamido‐2‐methylpropanesulfonic acid) (PAMPs) were examined by cyclic voltammetry, FT‐IR spectroscopy, UV‐vis spectroscopy, optical switching and current density measurements. Solid state devices made of PV films sandwiched with PANI as a counter electrode have switching times of 100–250 ms. 40 Bilayer films of PV/PAMPs show high contrast (ΔT = 61%) in 0.1 M NaClO4 liquid electrolyte solution and CE as high as 57 cm2 · C−1, one of the highest reported so far for any bipyridinium salt system.

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Influence of a Melt Flow on Generation of Functionally Graded Structure in Bulk Polymeric Materials under Uniaxial Thermal Gradient
Authors: Koide Satoshi , Asakawa Naoki , Inoue Yoshio , Yazawa Koji
Published: December 2007

A mechanism for the generation of the compositional gradient along the long axis for poly(ε‐caprolactone) (PCL)/poly(ethylene oxide) (PEO) blend under uniaxial thermal gradient was proposed by observations of the convection of polymer using graphite powder as a visual probe. The convection under the thermal gradient promoted the transfer of PCL into the liquid phase from the interface of PEO crystallites. The convex downward shape of the solid–liquid interface indicates the generation of the compositional gradient along the radial direction. By dissolution of PEO, a porous scaffold with a porosity gradient structure along the longitudinal direction was fabricated.

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Synthesis of Poly(N‐aryl‐2,7‐carbazole)s for Efficient Blue Electroluminescence Materials
Authors: Koguchi Ryohei , Kobayashi Norifumi , Shinnai Toshinobu , Oikawa Kazuma , Tsuchiya Kazuhiko , Kijima Masashi
Published: December 2007

Several poly(N‐phenyl‐2,7‐carbazole)s that have dialkoxy groups at the m‐ and p‐positions (PmpCzDC, PmpPhDC, PmpCBiDC, PmpEHC), a silyl group at the p‐position (PpPhDSiC), and a diphenylamino group (PmPhDAC, PmEHAC) at the m‐position of the N‐phenyl portion are synthesized, and their optical properties are characterized. These polymers have been used as emitting layer materials of organic light‐emitting diode (OLED) devices that have a configuration of ITO/PEDOT(PSS)/polymer/CsF/Al. The OLED devices embedded with PmpCzDC, PmpPhDC, and PmpEHC show intense luminance of about 15 000 cd · m−2 with efficiencies of about 1 cd · A−1, while the devices embedded with PpPhDSiC, PmPhDAC, and PmEHAC show less luminance but retain the color purity of blue emission under a wide range of applied voltages.

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Macromol. Chem. Phys. 24/2007
Authors: Papaioannou Emmanuel H. , Liakopoulou‐Kyriakides Maria , Papi Rigini M. , Kyriakidis Dimitrios A.
Published: December 2007

Cover: The cover illustrates a non‐covalent strategy for the preparation of molecularly imprinted polymers for cholecystokinin C‐terminal pentapeptide (CCK‐5) recognition. Copolymerization of methacrylic acid and ethylene glycol dimethacrylate in the presence of CCK‐5 resulted in a polymer able to recognize CCK‐5 and larger C‐terminal CCK fragments, such as CCK‐8. Further details can be found in the article by E. H. Papaioannou, M. Liakopoulou‐Kyriakides,* R. M. Papi, and D. A. Kyriakidis on page 2621.
A New Concept for an Alkaline Developable Positive‐Tone Resist: Molecular Resist Utilizing Acid Catalyzed Isomerization from Oxabenzonorbornadiene to Naphthol
Authors: Mori Hajime , Nomura Eisaku , Hosoda Asao , Miyake Yasuhito , Taniguchi Hisaji
Published: December 2007

A novel positive‐tone molecular resist possessing oxabenzonorbornadiene moiety was developed for electron‐beam (EB) lithography. The synthesized resist material showed relatively high glass transition temperature and readily formed uniform amorphous films on a silicon wafer. The sensitivity of an EB resist was ca. 8 µC · cm−2 and line and space patterns of 200 nm could be fabricated. The promising feature of the resist materials is that no outgassed products from base matrixes are theoretically produced under the exposure and post‐exposure bake procedure.

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Decision making in Parkinson's disease: Analysis of behavioral and physiological patterns in the Iowa gambling task
Authors: Kobayakawa Mutsutaka , Koyama Shinichi , Mimura Masaru , Kawamura Mitsuru
Published: December 2007

Recent studies suggest that social recognition processes are affected by Parkinson's disease (PD). However, whether PD patients exhibit behavioral changes is still controversial. The purpose of the present study was to examine the decision making of PD patients performing the Iowa Gambling Task (IGT). We recruited a large number of early, nondemented PD patients for the IGT. We also recorded the skin conductance responses (SCRs) during the task as a measure of emotional arousal. Compared with the normal control (NC) subjects, PD patients selected more disadvantageous decks in the IGT, and their SCRs were lower than those of NC subjects before making decisions and after receiving reward or punishment. The tendency toward risky choices was not correlated with age, education, global cognitive function, or the severity of the disease. These results confirmed that the decision making of PD patients was affected by the disease, rather than by other cognitive functions; moreover, such behavior was related to lower emotional responses. Behavioral and SCR patterns of PD patients were similar to those of amygdala‐damaged patients. The response bias toward risky choices in PD may be explained by the dysfunction of the amygdala, which is known to be involved in risk evaluation. © 2007 Movement Disorder Society
Electrophysiological signs and the prevalence of adverse effects of acetylcholinesterase inhibitors in patients with myasthenia gravis
Authors: Punga Anna Rostedt , Sawada Mikio , Stålberg Erik V.
Published: December 2007

The aim of this prospective study was to assess whether extra discharges (EDs), sometimes following the compound muscle action potential, could be used as a neurophysiological indicator of overdose of acetylcholinesterase inhibitors (AChEIs) in patients with myasthenia gravis (MG). The characteristics and frequency of EDs were explored and the correlation of EDs with cholinergic side effects was also determined. Twenty‐two MG patients (14 women, 8 men; 61 ± 16 years of age) with daily AChEI treatment were examined. The mean disease duration was 10 years (range 2–62 years) and all patients had been treated with AChEI since MG onset. Both single and repetitive stimulation of the ulnar and accessory nerves were performed before and 60 min after oral pyridostigmine bromide (PB) administration and after additional edrophonium injection. Fatigue, side effects, and AChE activity in blood were assessed before and 60 min after PB intake. The daily dose of PB ranged from 150 to 900 mg/day. Fourteen patients (64%) experienced daily cholinergic adverse effects, and muscarinic side effects correlated with AChE activity. Eleven patients (50%) developed EDs after oral PB. Among the eight patients with daily nicotinic side effects, EDs were significantly (P < 0.05) more common. Additionally, older patients were more prone to develop cholinergic side effects and EDs. Thus, when EDs are found, patients should be asked about daily muscular symptoms, which may be related to AChEI treatment and not solely to MG. Muscle Nerve, 2007
Optimal timing of switches between product sales for sports and entertainment tickets
Authors: Drake Matthew J. , Duran Serhan , Griffin Paul M. , Swann Julie L.
Published: December 2007

Like airlines and hotels, sports teams and entertainment venues can benefit from revenue management efforts for their ticket sales. Teams and entertainment venues usually offer bundles of tickets early in their selling horizon and put single‐event tickets on sale at a later date; these organizations must determine the best time to offer individual tickets because both types of ticket sales consume the same fixed inventory. We model the optimal a priori timing decision for a seller with a fixed number of identical tickets to switch from selling the tickets as fixed bundles to individual tickets to maximize the revenue realized before the start of the performance season. We assume that bundle and single‐ticket customers each arrive according to independent, nonhomogeneous Markovian death processes with a linear death rate that can vary over time and that the benefit from selling a ticket in a package is higher than from selling the ticket individually. We characterize the circumstances in which it is optimal for the seller to practice mixed bundling and when the seller should only sell bundles or individual tickets, and we establish comparative statics for the optimal timing decision for the special case of constant customer arrival rates. We extend our analytical results to find the optimal time for offering two groups of tickets with high and low demand. Finally, we apply the timing model to a data set obtained from the sports industry. © 2007 Wiley Periodicals, Inc. Naval Research Logistics, 2008
Optimal stabilizing controllers for linear discrete‐time stochastic systems
Authors: Feng Jun‐E , Lam James , Xu Shengyuan , Shu Zhan
Published: December 2007

The relationship between the spectral radius and the decay rate for discrete stochastic systems is investigated. Several equivalent conditions are obtained, which guarantee a specified decay rate of the closed‐loop systems. Based on the relationship, this paper provides a design method for state feedback controllers, which ensure that the closed‐loop systems converge as fast as possible. Finally, a numerical example is used to illustrate the developed method. Copyright © 2007 John Wiley & Sons, Ltd.
Knowledge of results and learning to tell the time in an adult male with an intellectual disability: a single‐subject research design
Authors: Applegate Samantha L , Rice Martin S , Stein Franklin , Maitra Kinsuk K
Published: December 2007

The present study investigated whether knowledge of results, in the form of visual and audible feedback, would increase the accuracy of time‐telling in an individual with an intellectual disability. A 19‐year‐old male with mild intellectual disability participated in this A1–B1–A2–B2 single‐subject study design. The task involved correctly identifying the time given on a computer. Data, based on the Wilcoxon signed‐rank test, showed that the participant demonstrated a greater number of correct responses during the intervention phases. Incorporating knowledge of results into a learning strategy for this individual with intellectual disability resulted in an increased ability to accurately identify the correct time on an analogue clock. There is a need to replicate the study design to increase the external validity and generalization of results. The strategies described in the present study may also be useful for occupational therapists who teach individuals with intellectual disability to gain skills in their everyday activities of daily living (ADLs). Copyright © 2007 John Wiley & Sons, Ltd.
Evidence of Notch pathway activation in the ectatic ducts of chronic pancreatitis
Authors: Bhanot UK , Köhntop R , Hasel C , Möller P
Published: December 2007

Ductal concretions in chronic pancreatitis (CP) are one of the causes of ductal obstruction, resulting in pancreatic ductal hypertension (PDH) and duct ectasia. Ductal epithelium subjected to chronic stress by PDH may undergo molecular alterations, thereby not only initiating and sustaining the inflammatory process but also activating molecules that have transforming potential. Acino‐ductal metaplasia and pancreatic intraepithelial neoplasia (PanIN) are frequently seen in CP. Using laser capture microdissection, cDNA microarrays and Ingenuity Pathways Analysis, we found an altered Notch pathway in the ectatic ducts of CP. The microarray data was further validated by real‐time PCR. We also found elevated transcripts of Notch receptors, Notch1 and Notch3 in microdissected ectatic ducts of CP. The Notch pathway ligands, Jagged/Delta‐like and a Notch target, HES‐related repressor protein (HERP), were up‐regulated in ectatic compared to normal pancreatic ducts, while another target of Notch, hairy/enhancer of split (HES), was down‐regulated. The transcripts of Delta‐like1 and Jagged1 were increased 3.7‐fold and 1.3‐fold, respectively, while those of HERP1 were elevated 2.4‐fold in the ectatic ducts of CP, compared to normal ducts. Immunohistochemistry showed that Jagged1 was not expressed in normal pancreatic ducts, while it was highly expressed in ectatic ducts. This pattern of Notch component alteration in ectatic ducts was mimicked to some extent in vitro in a human pancreatic duct epithelial (HPDE) cell line, when subjected to a pressure of 200 mmHg for 24 h. Therefore, we conclude that in the ectatic ducts of CP, PDH activates signalling pathways such as Notch, which have transforming potential. Copyright © 2007 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.
Gremlin localization and expression levels partially differentiate idiopathic interstitial pneumonia severity and subtype
Authors: Myllärniemi M , Vuorinen K , Pulkkinen V , Kankaanranta H , Aine T , Salmenkivi K , Keski‐Oja J , Koli K , Kinnula VL
Published: December 2007

Idiopathic pulmonary fibrosis (IPF) (histopathology of usual interstitial pneumonia, UIP) and non‐specific interstitial pneumonia (NSIP) are diseases characterized by loss of normal lung architecture and function. The differential diagnosis between IPF/UIP and NSIP may be difficult. The levels of bone morphogenetic protein (BMP)‐4 antagonist gremlin are up‐regulated in IPF/UIP. The present study was performed to clarify whether the localization or the mRNA expression of gremlin or BMP‐4 could be used in the differential diagnosis or assessment of severity of IPF/UIP and NSIP. Gremlin and BMP‐4 immunoreactivities were quantitated from 24 UIP and 12 NSIP lung specimens. Quantitative real‐time polymerase chain reaction analyses were performed to compare gremlin and BMP‐4 expression between UIP (n = 8) and NSIP (n = 5) biopsies. Immunohistochemical positivity and mRNA levels were correlated to lung function parameters. In IPF/UIP biopsies, gremlin was detected mainly in the thickened lung parenchyma, whereas in NSIP it was observed in the alveolar epithelium. BMP‐4‐positive (BMP‐4+) cells were detected solely in the alveolar wall. The percentage of gremlin‐positive area was higher in IPF/UIP (5.1 ± 0.6) than in NSIP (1.8 ± 0.7) (n = 36, p < 0.0001). Gremlin mRNA levels were higher in advanced UIP (p = 0.008) and NSIP (p = 0.007) biopsies than in the normal control lung. A negative correlation was found between the specific diffusion capacity corrected for alveolar volume (DLCO/VA) and gremlin mRNA levels (r = − 0.69, p = 0.007). The highest numbers of BMP‐4+ cells were found in NSIP biopsies. BMP‐4 mRNA levels correlated positively with forced vital capacity (r = 0.801, p < 0.0001) and diffusion capacity. Parenchymal gremlin immunoreactivity is thus suggestive of a UIP‐type interstitial pneumonia. Gremlin expression levels correlating negatively and BMP‐4 levels positively with disease severity support recent observations of a fibroprotective role for the BMPs. Copyright © 2007 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.
The significance of biochemical and molecular sample integrity in brain proteomics and peptidomics: Stathmin 2‐20 and peptides as sample quality indicators
Authors: Sköld Karl , Svensson Marcus , Norrman Mathias , Sjögren Benita , Svenningsson Per , Andrén Per E.
Published: December 2007

Comparisons of transcriptional and translational expression in normal and abnormal states are important to reach an understanding of pathogenesis and pathophysiology. Maintaining the biochemical, molecular, and structural sample integrity is essential for correct sample comparisons. We demonstrate that both proteins and neuropeptides, including their PTMs, are subjected to massive degradation in the brain already 1 min postmortem. Further, markers for determining the integrity and status of a biological sample were identified. The protein fragment stathmin 2‐20 correlated well with the general level of postmortem degradation and may serve as a sample quality indicator for future work, both in animal and human postmortem brains. Finally, a novel method for preventing degradation of proteins and peptides in postmortem tissue is presented using rapid and uniform conductive heat transfer on tissue prior to the actual sample preparation procedures, which enables the relatively low‐abundant neuropeptides to remain intact, minimizes degradation of proteins by proteolysis, and conserves the PTMs of the neuropeptides.
“Glyco‐peakfinder” – de novo composition analysis of glycoconjugates
Authors: Maass Kai , Ranzinger René , Geyer Hildegard , von der Lieth Claus‐Wilhelm , Geyer Rudolf
Published: December 2007

Mass spectrometric techniques are the key technology for rapid and reliable glycan analysis. However, the lack of robust, dependable, and freely available software for the (semi‐) automatic annotation of mass spectra is still a severe bottleneck that hampers their rapid interpretation. In this article the “Glyco‐Peakfinder” web‐service is described allowing de novo determination of glycan compositions from their mass signals. Starting from a basic set of mandatory masses of glycan components, the calculation can be performed without any knowledge concerning the biological background of the sample or the fragmentation technique used. “Glyco‐Peakfinder” assigns all types of fragment ions including monosaccharide cross‐ring cleavage products and multiply charged ions. It provides full user control to handle modified glycans (persubstituted molecules, reducing‐end modifications, glycoconjugates) and ion types. The formula applied to calculate the fragment masses and an outline of the implemented algorithm are discussed. A systematic evaluation of the dependence of all factors influencing the computation time revealed strikingly different impact of the individual calculation steps. To provide access to known carbohydrate structures a “composition search” in the open access database GLYCOSCIENCES.de can be performed. The service is available at the URL: www.eurocarbdb.org/applications/ms‐tools.
Phosphorylation‐regulated cleavage of the reticulon protein Nogo‐B by caspase‐7 at a noncanonical recognition site
Authors: Schweigreiter Rüdiger , Stasyk Taras , Contarini Igea , Frauscher Silke , Oertle Thomas , Klimaschewski Lars , Huber Lukas A. , Bandtlow Christine E.
Published: December 2007

Reticulons (RTNs) are a large family of transmembrane proteins present throughout the eukaryotic domain in virtually every cell type. Despite their wide distribution, their function is still mostly unknown. RTN4, also termed Nogo, comes in three isoforms, Nogo‐A, ‐B, and ‐C. While Nogo‐A has been described as potent inhibitor of nerve growth, Nogo‐B has been implicated in vascular remodeling and regulation of apoptosis. We show here that Nogo‐B gets cleaved by caspase‐7, but not caspase‐3, during apoptosis at a caspase nonconsensus site. By a combination of MS and site‐directed mutagenesis we demonstrate that proteolytic processing of Nogo‐B is regulated by phosphorylation of Ser16 within the cleavage site. We present cyclin‐dependent kinase (Cdk)1 and Cdk2 as kinases that phosphorylate Nogo‐B at Ser16 in vitro. In vivo, cleavage of Nogo‐B is markedly increased in Schwann cells in a lesion model of the rat sciatic nerve. Taken together, we identified an RTN protein as one out of a selected number of caspase targets during apoptosis and as a novel substrate for Cdk1 and 2. Furthermore, our data support a functionality of caspase‐7 that is distinct from closely related caspase‐3.
Myocardial ischemia/reperfusion causes VDAC phosphorylation which is reduced by cardioprotection with a p38 MAP kinase inhibitor
Authors: Schwertz Hansjörg , Carter Justin M. , Abdudureheman Mulati , Russ Martin , Buerke Ute , Schlitt Axel , Müller‐Werdan Ursula , Prondzinsky Roland , Werdan Karl , Buerke Michael
Published: December 2007

Myocardial ischemia (MI) and reperfusion (R) results in activation of the p38 MAP kinase pathway. This pathway phosphorylates transcription factors and cytoplasmic proteins leading to expression of adhesion molecules and cytokines, increased neutrophil activation, and finally, myocardial necrosis and apoptosis. We studied the effects of a p38 MAP kinase inhibitor, PD169316, on cardioprotection, protein expression, and tyrosine phosphorylation, in a rabbit model of 1 h of (MI) and 3 h of (R). PD169316 administered just before (R) significantly reduced myocardial neutrophil accumulation, necrosis area (28.4 ± 7.9% vs. 56.4 ± 7.9% necrosis/AAR), and CK release compared to a vehicle treated group (p<0.05). We found several proteins altered in expression following MI + R alone or with p38 inhibition including myofilament proteins, energetics proteins, heat shock proteins, and the mitochondrial porin VDAC‐1. p38 MAPK inhibition significantly reduced the phosphorylation of VDAC‐1 which is a known mitochondrial regulator of cell survival. Thus, p38 MAP kinase inhibition with PD169316 is cardioprotective, reduces neutrophil activation, and controls protein expression and phosphorylation in MI and reperfusion.