bluuebunny/crossref_metadata_2025 huggingface dataset:
Ecological Genomics of Marine Picocyanobacteria
Authors: Scanlan D. J. , Ostrowski M. , Mazard S. , Dufresne A. , Garczarek L. , Hess W. R. , Post A. F. , Hagemann M. , Paulsen I. , Partensky F.
Published: June 2009

Marine picocyanobacteria of the generaProchlorococcusandSynechococcusnumerically dominate the picophytoplankton of the world ocean, making a key contribution to global primary production.Prochlorococcuswas isolated around 20 years ago and is probably the most abundant photosynthetic organism on Earth. The genus comprises specific ecotypes which are phylogenetically distinct and differ markedly in their photophysiology, allowing growth over a broad range of light and nutrient conditions within the 45°N to 40°S latitudinal belt that they occupy.SynechococcusandProchlorococcusare closely related, together forming a discrete picophytoplankton clade, but are distinguishable by their possession of dissimilar light-harvesting apparatuses and differences in cell size and elemental composition.Synechococcusstrains have a ubiquitous oceanic distribution compared to that ofProchlorococcusstrains and are characterized by phylogenetically discrete lineages with a wide range of pigmentation. In this review, we put our current knowledge of marine picocyanobacterial genomics into an environmental context and present previously unpublished genomic information arising from extensive genomic comparisons in order to provide insights into the adaptations of these marine microbes to their environment and how they are reflected at the genomic level.
Challenging a Paradigm: the Role of DNA Homology in Tyrosine Recombinase Reactions
Authors: Rajeev Lara , Malanowska Karolina , Gardner Jeffrey F.
Published: June 2009

A classical feature of the tyrosine recombinase family of proteins catalyzing site-specific recombination, as exemplified by the phage lambda integrase and the Cre and Flp recombinases, is the ability to recombine substrates sharing very limited DNA sequence identity. Decades of research have established the importance of this short stretch of identity within the core regions of the substrates. Since then, several new enzymes that challenge this paradigm have been discovered and require the role of sequence identity in site-specific recombination to be reconsidered. The integrases of the conjugative transposons such as Tn916, Tn1545, and CTnDOT recombine substrates with heterologous core sequences. The integrase of the mobilizable transposon NBU1 performs recombination more efficiently with certain core mismatches. The integration of CTX phage and capture of gene cassettes by integrons also occur by altered mechanisms. In these systems, recombination occurs between mismatched sequences by a single strand exchange. In this review, we discuss literature that led to the formulation of the current strand-swapping isomerization model for tyrosine recombinases. The review then focuses on recent developments on the recombinases that challenged the paradigm that was derived from the studies of early systems.
Tumultuous Relationship between the Human Immunodeficiency Virus Type 1 Viral Infectivity Factor (Vif) and the Human APOBEC-3G and APOBEC-3F Restriction Factors
Authors: Henriet Simon , Mercenne Gaëlle , Bernacchi Serena , Paillart Jean-Christophe , Marquet Roland
Published: June 2009

The viral infectivity factor (Vif) is dispensable for human immunodeficiency virus type 1 (HIV-1) replication in so-called permissive cells but is required for replication in nonpermissive cell lines and for pathogenesis. Virions produced in the absence of Vif have an aberrant morphology and an unstable core and are unable to complete reverse transcription. Recent studies demonstrated that human APOBEC-3G (hA3G) and APOBEC-3F (hA3F), which are selectively expressed in nonpermissive cells, possess strong anti-HIV-1 activity and are sufficient to confer a nonpermissive phenotype. Vif induces the degradation of hA3G and hA3F, suggesting that its main function is to counteract these cellular factors. Most studies focused on the hypermutation induced by the cytidine deaminase activity of hA3G and hA3F and on their Vif-induced degradation by the proteasome. However, recent studies suggested that several mechanisms are involved both in the antiviral activity of hA3G and hA3F and in the way Vif counteracts these antiviral factors. Attempts to reconcile the studies involving Vif in virus assembly and stability with these recent findings suggest that hA3G and hA3F partially exert their antiviral activity independently of their catalytic activity by destabilizing the viral core and the reverse transcription complex, possibly by interfering with the assembly and/or maturation of the viral particles. Vif could then counteract hA3G and hA3F by excluding them from the viral assembly intermediates through competition for the viral genomic RNA, by regulating the proteolytic processing of Pr55
Gag
, by enhancing the efficiency of the reverse transcription process, and by inhibiting the enzymatic activities of hA3G and hA3F.
Signals, Regulatory Networks, and Materials That Build and Break Bacterial Biofilms
Authors: Karatan Ece , Watnick Paula
Published: June 2009

Biofilms are communities of microorganisms that live attached to surfaces. Biofilm formation has received much attention in the last decade, as it has become clear that virtually all types of bacteria can form biofilms and that this may be the preferred mode of bacterial existence in nature. Our current understanding of biofilm formation is based on numerous studies of myriad bacterial species. Here, we review a portion of this large body of work including the environmental signals and signaling pathways that regulate biofilm formation, the components of the biofilm matrix, and the mechanisms and regulation of biofilm dispersal.
Enantioselective synthesis of structurally intricate and complementary polyoxygenated building blocks of Spongistatin 1 (Altohyrtin A)
Authors: Braun Alain , Cho Il Hwan , Ciblat Stephane , Clyne Dean , Forgione Pat , Hart Amy C. , Huang Guoxiang , Kim Jungchul , Modolo Isabelle , Paquette Leo A. , Peng Xiaowen , Pichlmair Stefan , Stewart Catherine A. , Wang Jizhou , Zuev Dmitry
Published: June 2009

Enantioselective approaches to the construction of four complex building blocks of the structurally intricate marine macrolide known as spongistatin 1 are presented. The first phase of the synthetic effort relies on a practical approach to a desymmetrized, enantiomerically pure spiroketal ring system incorporating rings A and B. Concurrently, the C17–C28 subunit, which houses one-fifth of the stereogenic centers of the target in the form of rings C and D, was assembled via a composite of stereocontrolled aldol condensations. Once arrival at the entire C1–C28 sector had been realized, routes were devised to provide two additional highly functionalized sectors consisting of C29–C44 and C38–C51. A series of subsequent transformations including cyclization of the E ring and hydroboration to afford the B-alkyl intermediate for the key Suzuki coupling to append the side chain took advantage of efficient stereocontrol. Ultimately, complete assembly and functionalization of the western EF sector of spongistatin was thwarted by an inoperative Suzuki coupling step intended to join the side chain to the C29–C44 sector, and later because of complications due to protecting groups, which precluded the complete elaboration of the late stage C29–C51 intermediate.
α-(Disilylallenyl) α-amino acid derivatives from the Claisen rearrangement of propargyl glycinates
Authors: Mohamed Mustafa , Brook Michael A.
Published: June 2009

Silylpropargyl glycinate esters undergo [3,3]-sigmatropic rearrangements to give 2-(disilylallenyl)glycine derivatives, interesting highly functional synthons, in moderate to good yield (30 to 85%) and in high diastereoselectivity when directed by a large silylpropargyl group (9:1 to 22:1). The highly functional amino acid, methyl (R)-2-(Boc-amino)-3,5-bis(trimethylsilyl)hexa-3,4-dienoate was isolated and characterized by X-ray crystal structure analysis.
A COMPARATIVE STUDY OF DATA SAMPLING TECHNIQUES FOR CONSTRUCTING NEURAL NETWORK ENSEMBLES
Authors: AKHAND M. A. H. , ISLAM MD. MONIRUL , MURASE KAZUYUKI
Published: June 2009

Ensembles with several classifiers (such as neural networks or decision trees) are widely used to improve the generalization performance over a single classifier. Proper diversity among component classifiers is considered an important parameter for ensemble construction so that failure of one may be compensated by others. Among various approaches, data sampling, i.e., different data sets for different classifiers, is found more effective than other approaches. A number of ensemble methods have been proposed under the umbrella of data sampling in which some are constrained to neural networks or decision trees and others are commonly applicable to both types of classifiers. We studied prominent data sampling techniques for neural network ensembles, and then experimentally evaluated their effectiveness on a common test ground. Based on overlap and uncover, the relation between generalization and diversity is presented. Eight ensemble methods were tested on 30 benchmark classification problems. We found that bagging and boosting, the pioneer ensemble methods, are still better than most of the other proposed methods. However, negative correlation learning that implicitly encourages different networks to different training spaces is shown as better or at least comparable to bagging and boosting that explicitly create different training spaces.
DYNAMIC COMPETITIVE PROBABILISTIC PRINCIPAL COMPONENTS ANALYSIS
Authors: LÓPEZ-RUBIO EZEQUIEL , ORTIZ-DE-LAZCANO-LOBATO JUAN MIGUEL
Published: June 2009

We present a new neural model which extends the classical competitive learning (CL) by performing a Probabilistic Principal Components Analysis (PPCA) at each neuron. The model also has the ability to learn the number of basis vectors required to represent the principal directions of each cluster, so it overcomes a drawback of most local PCA models, where the dimensionality of a cluster must be fixed a priori. Experimental results are presented to show the performance of the network with multispectral image data.
AN ACTION GENERATION MODEL BY USING TIME SERIES PREDICTION AND ITS APPLICATION TO ROBOT NAVIGATION
Authors: GOUKO MANABU , ITO KOJI
Published: June 2009

This paper proposes an action generation model which consists of many motor primitive modules. The motor primitive modules output motor commands based on sensory information. Complicated behavior is generated by sequentially switching the modules. The model also has a prediction unit. This unit predicts which module will be used for current action generation. We have confirmed the effectiveness of the model by applying it to a robot navigation task simulation, and have investigated the influence of the prediction on the action generation.
NONLINEAR SYSTEM IDENTIFICATION BASED ON INTERNAL RECURRENT NEURAL NETWORKS
Authors: PUSCASU GHEORGHE , CODRES BOGDAN , STANCU ALEXANDRU , MURARIU GABRIEL
Published: June 2009

A novel approach for nonlinear complex system identification based on internal recurrent neural networks (IRNN) is proposed in this paper. The computational complexity of neural identification can be greatly reduced if the whole system is decomposed into several subsystems. This approach employs internal state estimation when no measurements coming from the sensors are available for the system states. A modified backpropagation algorithm is introduced in order to train the IRNN for nonlinear system identification. The performance of the proposed design approach is proven on a car simulator case study.
MODELING AND OPTIMIZATION OF A PHARMACEUTICAL FORMULATION SYSTEM USING RADIAL BASIS FUNCTION NETWORK
Authors: ANAND P. , SIVA PRASAD B. V. N. , VENKATESWARLU CH.
Published: June 2009

A Pharmaceutical formulation is composed of several formulation factors and process variables. Quantitative model based pharmaceutical formulation involves establishing mathematical relations between the formulation variables and the resulting responses, and optimizing the formulation conditions. In a formulation system involving several objectives, the desirable formulation conditions for one property may not always be desirable for other characteristics, thus leading to the problem of conflicting objectives. Therefore, efficient modeling and optimization techniques are needed to devise an optimal formulation system. In this work, a novel method based on radial basis function network (RBFN) is proposed for modeling and optimization of pharmaceutical formulations involving several objectives. This method has the advantage that it automatically configures the RBFN using a hierarchically self organizing learning algorithm while establishing the network parameters. This method is evaluated by using a trapidil formulation system as a test bed and compared with that of a response surface method (RSM) based on multiple regression. The simulation results demonstrate the better performance of the proposed RBFN method for modeling and optimization of pharmaceutical formulations over the regression based RSM technique.
THE SCALAR UNPARTICLE EFFECT ON THE CHARGED LEPTON ELECTRIC DIPOLE MOMENT
Authors: ILTAN E. O.
Published: June 2009

We study the charged lepton electric dipole moment which is induced by the scalar unparticle mediation and we predict the appropriate range for the free parameters appearing in the effective Lagrangian which drives the unparticle-standard model lepton interactions. We observe that the charged lepton electric dipole moment is strongly sensitive to the scaling dimension du of the unparticle and the new couplings in the effective interaction. Furthermore, we see that the current experimental limits of charged lepton electric dipole moments can ensure an appropriate range for these free parameters.
(NON)TRIVIALITY OF PURE SPINORS AND EXACT PURE SPINOR–RNS MAP
Authors: POLYAKOV DIMITRI
Published: June 2009

All the BRST-invariant operators in pure spinor formalism in d = 10 can be represented as BRST commutators, such as [Formula: see text] where λ+ is the U(5) component of the pure spinor transforming as [Formula: see text]. Therefore, in order to secure nontriviality of BRST cohomology in pure spinor string theory, one has to introduce "small Hilbert space" and "small operator algebra" for pure spinors, analogous to those existing in RNS formalism. As any invariant vertex operator in RNS string theory can also represented as a commutator V = {Q brst , LV} where L = -4c∂ξξe-2ϕ, we show that mapping [Formula: see text] to L leads to identification of the pure spinor variable λα in terms of RNS variables without any additional nonminimal fields. We construct the RNS operator satisfying all the properties of λα and show that the pure spinor BRST operator ∮λαdα is mapped (up to similarity transformation) to the BRST operator of RNS theory under such a construction.
MULTIPARTITE COHERENT ENTANGLED STATE OF CONTINUOUS VARIABLES: STRUCTURE AND GENERATION
Authors: HU LI-YUN , FAN HONG-YI
Published: June 2009

Motivated by the new approach to finding multipartite entangled state representation [Int. J. Mod. Phys. A22, 4481 (2007)], we construct the multipartite coherent entangled state (MCES) of continuous variables which exhibits both coherent state's and entangled state's properties. A protocol of generating such an MCES is proposed by using beam splitters in a sequence. Applications of MCES in studying generalized Wigner function, squeezing and quantum teleportation are discussed.
INVERSE SQUARE PROBLEM AND so(2, 1) SYMMETRY IN NONCOMMUTATIVE SPACE
Authors: GIRI PULAK RANJAN
Published: June 2009

We study the quantum mechanics of a system with inverse square potential in noncommutative space. Both the coordinates and momenta are considered to be noncommutative, which breaks the original so(2, 1) symmetry. The energy levels and eigenfunctions are obtained. The generators of the so(2, 1) algebra are also studied in noncommutative phase space and the commutators are calculated, which shows that the commutators obtained in noncommutative space is not closed. However the commutative limit Θ, [Formula: see text] for the commutators smoothly go to the standard so(2, 1) algebra.
THE SU(2) ⊗ U(1) ELECTROWEAK MODEL BASED ON THE NONLINEARLY REALIZED GAUGE GROUP
Authors: BETTINELLI D. , FERRARI R. , QUADRI A.
Published: June 2009

The electroweak model is formulated on the nonlinearly realized gauge group SU (2) ⊗ U (1). This implies that in perturbation theory no Higgs field is present. This paper provides the effective action at the tree level, the Slavnov–Taylor identity (necessary for the proof of physical unitarity), the local functional equation (used for the control of the amplitudes involving the Goldstone bosons) and the subtraction procedure (nonstandard, since the theory is not power-counting renormalizable). Particular attention is devoted to the number of independent parameters relevant for the vector mesons; in fact, there is the possibility of introducing two mass parameters. With this choice the relation between the ratio of the intermediate vector meson masses and the Weinberg angle depends on an extra free parameter.

We briefly outline a method for dealing with γ5 in dimensional regularization. The model is formulated in the Landau gauge for sake of simplicity and conciseness. The QED Ward identity has a simple and intriguing form.
FORWARD PHYSICS AT THE LHC: ELASTIC SCATTERING
Authors: FIORE R. , JENKOVSZKY L. , ORAVA R. , PREDAZZI E. , PROKUDIN A. , SELYUGIN O.
Published: June 2009

The following effects in the nearly forward ("soft") region of the LHC are proposed to be investigated:

• At small |t| the fine structure of the cone (Pomeron) should be scrutinized: (a) a break of the cone near t ≈ -0.1 GeV 2, due to the two-pion threshold, and required by t-channel unitarity, and (b) possible small-period oscillations between t = 0 and the dip region.

• In measuring the elastic pp scattering and total pp cross-section at the LHC, the experimentalists are urged to treat the total cross-section σt, the ratio ρ of real to imaginary part of the forward scattering amplitude, the forward slope B and the luminosity [Formula: see text] as free parameters, and to publish model-independent results on dN/dt.

• Of extreme interest are the details of the expected diffraction minimum in the differential cross-section. Its position, expected in the interval 0.4 < -t < 1 GeV 2 at the level of about 10-2 mb · GeV -2–10-1 mb · GeV -2, cannot be predicted unambiguously, and its depth, i.e. the ratio of dσ/dt at the minimum to that at the subsequent maximum (about -t = 5 GeV 2, which is about 5) is of great importance.

• The expected slow-down with increasing |t| of the shrinkage of the second cone (beyond the dip-bump), together with the transition from an exponential to a power decrease in -t, will be indicative of the transition from "soft" to "hard" physics. Explicit models are proposed to help in quantifying this transition.

• In a number of papers a limiting behavior, or saturation of the black disk limit (BDL), was predicted. This controversial phenomenon shows that the BDL may not be the ultimate limit, instead a transition from shadow to antishadow scattering may by typical of the LHC energy scale.
FRAMES FOR SUPERSYMMETRY
Authors: DORAN C. F. , FAUX M. G. , GATES S. J. , HÜBSCH T. , IGA K. M. , LANDWEBER G. D.
Published: June 2009

We explain how the redefinitions of supermultiplet component fields, comprising what we call "frame shifts," can be used in conjuction with the graphical technology of multiplet Adkinras to render manifest the reducibility of off-shell representations of supersymmetry. This technology speaks to possibility of organizing multiplet constraints in a way which complements and extends the possibilities afforded by superspace methods.
HOLOGRAPHIC ENTANGLEMENT ENTROPY AT FINITE TEMPERATURE
Authors: BAH IBRAHIMA , FARAGGI ALBERTO , PANDO ZAYAS LEOPOLDO A. , TERRERO-ESCALANTE CÉSAR A.
Published: June 2009

Using a holographic proposal for the entanglement entropy we study its behavior in various supergravity backgrounds. We are particularly interested in the possibility of using the entanglement entropy as way to detect transitions induced by the presence horizons. We consider several geometries with horizons: the black hole in AdS3, nonextremal D p-branes, dyonic black holes asymptotically to AdS4 and also Schwarzschild black holes in global AdS p coordinates. Generically, we find that the entanglement entropy does not exhibit a transition, that is, one of the two possible configurations always dominates.
THE HISTORY OF THE GURALNIK, HAGEN AND KIBBLE DEVELOPMENT OF THE THEORY OF SPONTANEOUS SYMMETRY BREAKING AND GAUGE PARTICLES
Authors: GURALNIK GERALD S.
Published: June 2009

I discuss historical material about the beginning of the ideas of spontaneous symmetry breaking and particularly the role of the paper by Guralnik, Hagen and Kibble in this development. I do so adding a touch of some more modern ideas about the extended solution-space of quantum field theory resulting from the intrinsic nonlinearity of nontrivial interactions.
MODEL DRIVEN DEVELOPMENT OF SEMANTIC WEB ENABLED MULTI-AGENT SYSTEMS
Authors: KARDAS GEYLANI , GOKNIL ARDA , DIKENELLI OGUZ , TOPALOGLU N. YASEMIN
Published: June 2009

Semantic Web evolution brought a new vision into agent research. The interpretation of this second generation web will be realized by autonomous computational entities, called agents, to handle the semantic content on behalf of their human users. Surely, Semantic Web environment has specific architectural entities and a different semantic which must be considered to model a Multi-agent System (MAS) within this environment. Hence, in this study, we introduce a MAS development process which supports the Semantic Web environment. Our approach is based on Model Driven Development (MDD) which aims to change the focus of software development from code to models. We first define an architecture for Semantic Web enabled MASs and then provide a MAS metamodel which consists of the first class meta-entities derived from this architecture. We also define a model transformation process for MDD of such MASs. We present a complete transformation process in which the source and the target metamodels, entity mappings between models and the implementation of the transformation for two different real MAS frameworks by using a well-known model transformation language are all included. In addition to the model-to-model transformation, the implementation of the model-to-code transformation is given as the last step of the system development process. The evaluation of the proposed development process by considering its use within the scope of a real commercial software project is also discussed.
COMPOSING SERVICES INTO STRUCTURED PROCESSES
Authors: ESHUIS RIK , GREFEN PAUL
Published: June 2009

Service composition languages like BPEL and many enactment tools only support structured process models, but most service composition approaches only consider unstructured process models. This paper defines an efficient algorithm that composes a set of cooperative services with their dependencies into a structured process. The algorithm takes as input a dependency graph and returns a structured process model that orchestrates the services while respecting their dependencies. The algorithm is embedded in a lightweight, semi-automated service composition approach, in which first dependencies between services are derived in a semi-automated way and next the algorithm is used to construct a structured composition. The approach has been implemented in a prototype that supports the dynamic formation and collaboration of dynamic virtual enterprises using cross-organizational service-oriented technology.
TOWARDS A SERVICE-ORIENTED MDA-BASED APPROACH TO THE ALIGNMENT OF BUSINESS PROCESSES WITH IT SYSTEMS: FROM THE BUSINESS MODEL TO A WEB SERVICE COMPOSITION MODEL
Authors: DE CASTRO VALERIA , MARCOS ESPERANZA , WIERINGA ROEL
Published: June 2009

In recent years, the automation of business processes has become one of the most prominent and promising uses of Web service technology. Consequently several languages have been created for the execution of business processes, making it possible to define new and more complex services or business processes which are implemented for example by means of Web service composition. Nevertheless, these kinds of languages are not suitable for use in the early stages of the development process of information systems. Special methodologies or techniques are therefore necessary to allow systems analysts to understand services from a business point of view, while facilitating the design and development of Web service composition. In this paper, we present a service-oriented approach to information system development that starts by identifying, through business modeling, the services required by the customers of a business, to make it possible to create a Web service composition model. This model will facilitate the transformation to specific languages for business process execution, thereby reducing the development efforts made in service-oriented applications. The method proposed is illustrated by means of a Web application for the management of medical images, which we have taken as a case study.
Reality of the Wigner Functions and Quantization
Authors: Nasiri Sadollah , Bahrami Samira
Published: June 2009

Here we use the extended phase space formulation of quantum statistical mechanics proposed in an earlier work to define an extended lagrangian for Wigner's functions (WFs). The extended action defined by this lagrangian is a function of ordinary phase space variables. The reality condition of WFs is employed to quantize the extended action. The energy quantization is obtained as a direct consequence of the quantized action. The technique is applied to find the energy states of harmonic oscillator, particle in the box, and hydrogen atom as the illustrative examples.
Information Infrastructure for Cooperative Research in Neuroscience
Authors: Durka P. J. , Blinowski G. J. , Klekowicz H. , Malinowska U. , Kuś R. , Blinowska K. J.
Published: June 2009

The paper describes a framework for efficient sharing of knowledge between research groups, which have been working for several years without flaws. The obstacles in cooperation are connected primarily with the lack of platforms for effective exchange of experimental data, models, and algorithms. The solution to these problems is proposed by construction of the platform (EEG.pl) with the semantic aware search scheme between portals. The above approach implanted in the international cooperative projects like NEUROMATH may bring the significant progress in designing efficient methods for neuroscience research.
The Phytoestrogen Quercetin Impairs Steroidogenesis and Angiogenesis in Swine Granulosa Cells In Vitro
Authors: Santini Sujen Eleonora , Basini Giuseppina , Bussolati Simona , Grasselli Francesca
Published: June 2009

Experimental evidence documents that nutritional phytoestrogens may interact with reproductive functions but the exact mechanism of action is still controversial. Since quercetin is one of the main flavonoids in livestock nutrition, we evaluated its possible effects on cultured swine granulosa cell proliferation, steroidogenesis, and redox status. Moreover, since angiogenesis is essential for follicle development, the effect of the flavonoid on Vascular Endothelial Growth Factor output by granulosa cells was also taken into account. Our data evidence that quercetin does not affect granulosa cell growth while it inhibits progesterone production and modifies estradiol 17β production in a dose‐related manner. Additionally, the flavonoid interferes with the angiogenic process by inhibiting VEGF production as well as by altering redox status. Since steroidogenesis and angiogenesis are strictly involved in follicular development, these findings appear particularly relevant, pointing out a possible negative influence of quercetin on ovarian physiology. Therefore, the possible reproductive impact of the flavonoid should be carefully considered in animal nutrition.
Depression with Panic Episodes and Coronary Vasospasm
Authors: Vidovich Mladen I. , Ahluwalia Aneet , Manev Radmila
Published: June 2009

Variant (Prinzmetal's) angina is an uncommon cause of precordial pain caused by coronary vasospasm and characterized by transient ST elevation and negative markers of myocardial necrosis. This is the case of a female patient with a prior history of depression and panic attacks who presented with recurrent symptoms including chest pain. A cardiac event monitor positively documented coronary vasospasm associated with anxiety-provoking chest pain, whereas the coronary arteries were angiographically normal. We noted that the frequency of angina attacks apparently increased during the period that coincided with the introduction of Bupropion SR for treatment of the patient's depression. Considering the possibility of bupropion-associated negative impact on coronary vasospasm, the antidepressant therapy was adjusted to exclude this drug. Although Prinzmetal's angina is relatively uncommon, we suspect that a routine use of cardiac event monitors in subjects with panic disorder might reveal a greater incidence of coronary vasospasm in this patient population.
The Studies of Conditions for Inducing Chirality to Cu(II) Complexes by Chiral Zn(II) and Ni(II) Complexes with Schiff Base
Authors: Akitsu Takashiro , Yamaguchi Jun , Uchida Naoki , Aritake Yoshikazu
Published: June 2009

Recently, we have discovered that some chiral Schiff‐base nickel(II) complexes induced d‐d bands of CD spectra of some achiral copper(II) complexes. However, the novel phenomenon could be observed only a few systems of hybrid materials or limited conditions so far. In order to test conditions about copper(II) ions, we investigated model systems (1) metal‐dendrimer (Cu‐PAMAM; G4‐NH2 terminal) containing relatively small amount of copper(II) ions (4.5 equivalent to PAMAM) for modeling separated systems of achiral copper(II) complex from chiral Schiff‐base nickel(II) or zinc(II) complexes, Bis(N‐R‐1‐naphtylethyl‐3,5‐dichlorosalicydenaminato)nickel(II) or zinc(II) by polymer matrix. (2) equilibrium of copper(II) N‐ethylethylenediamine complexes to measure absorption spectra of d‐d band, pH, and electron conductivity during titration of copper(II) ions. The results showed that (1) 4.5Cu‐PAMAM could not be induced their d‐d bands by the chiral nickel(II) or zinc(II) complexes, which suggested that separation by polymers prevented from inducing CD peaks. (2) Although 36Cu‐PAMAM was known, uncoordinated copper(II) ions excess to ligands mainly attributed to increase electron conductivity by remained ions in methanol solutions, which was not associated with intermolecular interaction or dipole moments being effective for the induced CD mechanism by using molecular recognition between neutral molecules of metal complexes.
Designing Zirconium Coated Polystyrene Colloids and Application
Authors: Chira Diana , Seo Seong S.
Published: June 2009

A simple technique has been developed to prepare core colloids that are modified using zirconium oxychloride, based on heating a solution of core colloid composites, consisting of poly (ethylenimine) (PEI) and zirconium oxychloride. The interaction of zirconium oxychloride with the polystyrene (PS) core colloids has been investigated using Fourier transform‐infrared spectroscopy (FT‐IR), energy dispersive X‐ray spectroscopy (EDX), and scanning electron microscopy (SEM) data. FT‐IR studies confirm the occurrence of amine groups present in PEI which are oxidized to carboxyl groups after the reaction. The EDX data and the SEM images confirm the presence of zirconium particles immobilized on the polystyrene surfaces. Demeton, a highly toxic nerve agent, was used due to its ability to easily bind through its organophosphate group illustrating a practical application of the PS‐PEI‐Zr particles. Attenuated Total Reflection (ATR) Spectroscopy was used to assess the interactions between the toxic nerve agent demeton‐S and the PS‐PEI‐Zr particles. The results show that the presented technique for coating polystyrene core colloids with zirconium was successfully accomplished, and the newly formed particles easily bond with demeton agents through the P=O functional group.
Application of Interval Arithmetic in the Evaluation of Transfer Capabilities by Considering the Sources of Uncertainty
Authors: Umapathy Prabha , Venkataseshaiah C. , Arumugam M. Senthil
Published: June 2009

Total transfer capability (TTC) is an important index in a power system with large volume of inter‐area power exchanges. This paper proposes a novel technique to determine the TTC and its confidence intervals in the system by considering the uncertainties in the load and line parameters. The optimal power flow (OPF) method is used to obtain the TTC. Variations in the load and line parameters are incorporated using the interval arithmetic (IA) method. The IEEE 30 bus test system is used to illustrate the proposed methodology. Various uncertainties in the line, load and both line and load are incorporated in the evaluation of total transfer capability. From the results, it is observed that the solutions obtained through the proposed method provide much wider information in terms of closed interval form which is more useful in ensuring secured operation of the interconnected system in the presence of uncertainties in load and line parameters.
High Specificity of Quantitative Methylation‐Specific PCR Analysis for MGMT Promoter Hypermethylation Detection in Gliomas
Authors: Parrella Paola , la Torre Antonella , Copetti Massimiliano , Valori Vanna M. , Barbano Raffaela , Notarangelo Angelo , Bisceglia Michele , Gallo Antonietta Pia , Balsamo Teresa , Poeta Maria Luana , Carella Massimo , Catapano Domenico , Parisi Salvatore , Dallapiccola Bruno , Maiello Evaristo , D′Angelo Vincenzo , Fazio Vito Michele
Published: June 2009

Normal brain tissue from 28 individuals and 50 glioma samples were analyzed by real‐time Quantitative Methylation‐Specific PCR (QMSP). Data from this analysis were compared with results obtained on the same samples by MSP. QMSP analysis demonstrated a statistically significant difference in both methylation level (P = .000009 Mann Whitney Test) and frequencies (P = .0000007, Z‐test) in tumour samples as compared with normal brain tissues. Although QMSP and MSP showed similar sensitivity, the specificity of QMSP analysis was significantly higher (93%; CI95%: 84%–100%) as compared with MSP (64%; 95%CI: 46%–82%). Our results suggest that QMSP analysis may represent a powerful tool to identify glioma patients that will benefit from alkylating agents chemotherapy.
Facile Synthesis of Highly Aligned Multiwalled Carbon Nanotubes from Polymer Precursors
Authors: Han Catherine Y. , Xiao Zhi-Li , Wang H. Hau , Lin Xiao-Min , Trasobares Susana , Cook Russell E.
Published: June 2009

We report a facile one‐step approach which involves no flammable gas, no catalyst, and no in situ polymerization for the preparation of well‐aligned carbon nanotube array. A polymer precursor is placed on top of an anodized aluminum oxide (AAO) membrane containing regular nanopore arrays, and slow heating under Ar flow allows the molten polymer to wet the template through adhesive force. The polymer spread into the nanopores of the template to form polymer nanotubes. Upon carbonization the resulting multi‐walled carbon nanotubes duplicate the nanopores morphology precisely. The process is demonstrated for 230, 50, and 20 nm pore membranes. The synthesized carbon nanotubes are characterized with scanning/transmission electron microscopies, Raman spectroscopy, and resistive measurements. Convenient functionalization of the nanotubes with this method is demonstrated through premixing CoPt nanoparticles in the polymer precursors.
Progressive Macular Hypomelanosis: A Rarely Diagnosed Hypopigmentation in Caucasians
Authors: Neynaber Sven , Kirschner Christina , Kamann Stefanie , Plewig Gerd , Flaig Michael J.
Published: June 2009

A 35-year-old woman who developed whitish macules on trunk and limbs at 12 years of age and observed a remarkable increase of the hypopigmentated lesions after her pregnancies at ages 29 and 32 years. Because of the highly characteristic clinical aspect and the light- and electron-microscopic histopathologic findings, we diagnosed progressive macular hypomelanosis (PMH). It is a nonscaly disorder with hypopigmented macules mainly on the trunk and is more often seen in young women. In contrast to some authors assuming the presence ofPropionibacterium spp.as a matter of principle in PMH, we report a case with no evidence forPropionibacterium spp.
Synthesis of Nanowires by Spray Pyrolysis
Authors: Pingali Kalyana C. , Deng Shuguang , Rockstraw David A.
Published: June 2009

Nanowires of carbon as well as nickel‐carbon (Ni‐C) were synthesized by spray‐pyrolysis. The carbon nanowires were synthesized using methanol as a precursor while the Ni‐C nanowires were obtained by using nickel chloride methanol solution as feed. It was found that low argon carrier gas flow rates (<100 cm3/min) and suitable reaction temperatures (∼700∘C) were found to be critical for the formation of wired structures. The formation of nanowires was quite sensitive to reaction temperature. Nanowires could not form at temperatures higher than 900∘C in the presence of hexane. Ruthenium chloride and nickel chloride dissolved in hexane and methanol resulted in carbon coated binary metallic nanoparticles. Morphological differences of carbon nanowires, Ni‐C wires and carbon coated binary nanoparticles were characterized by scanning electron microscopy (SEM) and energy‐dispersive X‐ray analysis (EDS). The formation mechanism for the wired structures is proposed to explain the structural results obtained.
Synthesis and Characterization of Birnessite and Cryptomelane Nanostructures in Presence of Hoffmeister Anions
Authors: Cheney Marcos A. , Jose Robin , Banerjee Arghya , Bhowmik Pradip K. , Qian Shizhi , Okoh Joseph M.
Published: June 2009

The effect of Hoffmeister anions Cl−, SO4 2−, and ClO4 − on the structure and morphology of birnessite and cryptomelane‐type manganese dioxide nanostructures, produced by the reduction reaction of KMnO4
and MnSO4
in aqueous acidic media, was studied. The syntheses were based on the decomposition of aqueous KMnO4 in presence of HCl for birnessite‐type and acidified MnSO4 for cryptomelane‐type manganese dioxide under soft hydrothermal conditions. They were characterized using X‐ray diffraction (XRD), transmission electron microscopy (TEM), and high‐resolution transmission electron microscopy (HRTEM) techniques. XRD patterns show the formation of birnessite for the first synthesis and a mixture of cryptomelane and birnessite‐types
MnO2 for the second synthesis. XRD data revealed that the Hoffmeister anions have a significant effect on the nanostructures of birnessite. The sulphate ion‐treated birnessite has the smallest crystals, whereas the chloride ion‐treated birnessite has the largest crystals. Their TEM and HRTEM studies revealed a transformation from nanoplatelet morphology for chloride‐treated samples to nanofibrous morphology for sulphate‐treated birnessite. For the cryptomelane nanostructures, Hoffmeister anions also show a profound effect on their crystalline structures as determined by XRD analyses revealing a transformation of the cryptomelane phase to birnessite phase of
MnO2. This transformation is also supported by TEM and HRTEM studies.
Synthesis of Poly[(3-(6-(9-anthracenylmethoxy)hexyl)thiophene)-co-(3-(6-bromohexyl)thiophene)] Postfunctionalized from Poly(3-(6-bromohexyl)thiophene): A Comparative Study of the Base Polymer with Its Chlorinated Analogous
Authors: Díaz-Alzamora F. R. , del Valle M. A. , Núñez C. M. , Zamora P. P. , Soto J. P. , Bernède J. C.
Published: June 2009

A synthetic method based on the postfunctionalization of a reactive homopolymer precursor, which allows for the preparation of different copolymers derived from poly(3-alkylthiophene), was studied. Although these groups decrease the solubility of the resultant material, they enable controlling the degree of substitution to obtain a material with improved spectroscopic (absorption and emission) properties making them useful for the fabrication of electronic devices, for example, solar cells and light-emitting diodes. Furthermore, a comparative study of two halogenated (Cl and Br) reactive poly(3-ω-haloalkyl)thiophenes was carried out.
Regulation of HSulf-1 Expression by Variant Hepatic Nuclear Factor 1 in Ovarian Cancer
Authors: Liu Peng , Khurana Ashwani , Rattan Ramandeep , He Xiaoping , Kalloger Steve , Dowdy Sean , Gilks Blake , Shridhar Viji
Published: June 2009

We recently identified HSulf-1 as a down-regulated gene in ovarian carcinomas. Our previous analysis indicated that HSulf-1 inactivation in ovarian cancers is partly mediated by loss of heterozygosity and epigenetic silencing. Here, we show that variant hepatic nuclear factor 1 (vHNF1), encoded by transcription factor 2 gene (TCF2, HNF1β), negatively regulates HSulf-1 expression in ovarian cancer. Immunoblot assay revealed that vHNF1 is highly expressed in HSulf-1–deficient OV207, SKOV3, and TOV-21G cell lines but not in HSulf-1–expressing OSE, OV167, and OV202 cells. By short hairpin RNA–mediated down-regulation of vHNF1 in TOV-21G cells and transient enhanced vHNF1 expression in OV202 cells, we showed that vHNF1 suppresses HSulf-1 expression in ovarian cancer cell lines. Reporter assay and chromatin immunoprecipitation experiments showed that vHNF1 is specifically recruited to HSulf-1 promoter at two different vHNF1-responsive elements in OV207 and TOV-21G cells. Additionally, down-regulation of vHNF1 expression in OV207 and TOV-21G cells increased cisplatin- or paclitaxel-mediated cytotoxicity as determined by both 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide and clonogenic assays and this effect was reversed by down-regulation of HSulf-1. Moreover, nude mice bearing TOV-21G cell xenografts with stably down-regulated vHNF1 were more sensitive to cisplatin- or paclitaxel-induced cytotoxicity compared with xenografts of TOV-21G clonal lines with nontargeted control short hairpin RNA. Finally, immunohistochemical analysis of 501 ovarian tumors including 140 clear-cell tumors on tissue microarrays showed that vHNF1 inversely correlates to HSulf-1 expression. Collectively, these results indicate that vHNF1 acts as a repressor of HSulf-1 expression and might be a molecular target for ovarian cancer therapy. [Cancer Res 2009;69(11):4843–50]
Promyelocytic Leukemia Protein is Required for Gain of Function by Mutant p53
Authors: Haupt Sue , di Agostino Silvia , Mizrahi Inbal , Alsheich-Bartok Osnat , Voorhoeve Mathijs , Damalas Alex , Blandino Giovanni , Haupt Ygal
Published: June 2009

Mutations in the p53 tumor suppressor are the most common genetic events in human cancer. These mutations not only result in a loss of wild-type p53 activity, but can also lead to a gain of new oncogenic properties. Understanding how these gained functions are regulated is in its infancy. In this study, we show that the promyelocytic leukemia (PML) protein is an important regulator of mutant p53. We show that PML interacts with mutant p53. Importantly, PML enhances the transcriptional activity of mutant p53. Unexpectedly, PML is required for the proliferation and colony formation of cancer cells bearing mutant p53. Down-regulation of PML expression inhibits the growth of mutant p53-expressing cancer cells, predominantly by promoting cell cycle arrest. Our results suggest that the tumor suppression function of PML depends on the status of p53. In the context of mutant p53, PML enhances its cancer-promoting activities. [Cancer Res 2009;69(11):4818–26]
Genomic Profiling of MicroRNAs in Bladder Cancer: miR-129 Is Associated with Poor Outcome and Promotes Cell Death In vitro
Authors: Dyrskjøt Lars , Ostenfeld Marie S. , Bramsen Jesper B. , Silahtaroglu Asli N. , Lamy Philippe , Ramanathan Ramshanker , Fristrup Niels , Jensen Jens L. , Andersen Claus L. , Zieger Karsten , Kauppinen Sakari , Ulhøi Benedicte P. , Kjems Jørgen , Borre Michael , Ørntoft Torben F.
Published: June 2009

microRNAs (miRNA) are involved in cancer development and progression, acting as tumor suppressors or oncogenes. Here, we profiled the expression of 290 unique human miRNAs in 11 normal and 106 bladder tumor samples using spotted locked nucleic acid–based oligonucleotide microarrays. We identified several differentially expressed miRNAs between normal urothelium and cancer and between the different disease stages. miR-145 was found to be the most down-regulated in cancer compared with normal, and miR-21 was the most up-regulated in cancer. Furthermore, we identified miRNAs that significantly correlated to the presence of concomitant carcinoma in situ. We identified several miRNAs with prognostic potential for predicting disease progression (e.g., miR-129, miR-133b, and miR-518c*). We localized the expression of miR-145, miR-21, and miR-129 to urothelium by in situ hybridization. We then focused on miR-129 that exerted significant growth inhibition and induced cell death upon transfection with a miR-129 precursor in bladder carcinoma cell lines T24 and SW780 cells. Microarray analysis of T24 cells after transfection showed significant miR-129 target down-regulation (P = 0.0002) and pathway analysis indicated that targets were involved in cell death processes. By analyzing gene expression data from clinical tumor samples, we identified significant expression changes of target mRNA molecules related to the miRNA expression. Using luciferase assays, we documented a direct link between miR-129 and the two putative targets GALNT1 and SOX4. The findings reported here indicate that several miRNAs are differentially regulated in bladder cancer and may form a basis for clinical development of new biomarkers for bladder cancer. [Cancer Res 2009;69(11):4851–60]
Intestinal Mucosal Inflammation Leads to Systemic Genotoxicity in Mice
Authors: Westbrook Aya M. , Wei Bo , Braun Jonathan , Schiestl Robert H.
Published: June 2009

Inflammatory bowel disease, including ulcerative colitis and Crohn's disease, substantially increases the risk of colorectal cancer. However, mechanisms linking mucosal inflammation to the sequence of dysplasia are incompletely understood. Whereas studies have shown oxidative damage to the colon, this study tests whether genotoxicity is elicited systemically by acute and chronic intestinal inflammation. In this study, genotoxic endpoints were assessed in peripheral leukocytes (DNA single- and double-stranded breaks and oxidative DNA damage) and normochromatic erythrocytes (micronuclei) during chemical or immune-mediated colitis. During three consecutive cycles of intestinal inflammation induced by dextran sulfate sodium administration, genotoxicity to peripheral leukocytes and erythroblasts was detected in both acute and chronic phases of dextran sulfate sodium–induced inflammation. Reactive oxygen species–mediated oxidative stress and DNA damage was confirmed with positive 8-oxoguanine and nitrotyrosine staining in peripheral leukocytes. Levels of DNA damage generally decreased during remission and increased during treatment, correlating with clinical symptoms and systemic inflammatory cytokine levels. In Gαi2−/− and interleukin-10−/− transgenic mice susceptible to immune-mediated colitis and inflammation-associated adenocarcinoma, similar levels of peripheral leukocyte and erythroblast genotoxicity were also observed. Moreover, this systemic genotoxicity was observed in mice with subclinical inflammation, which was further elevated in those with severe mucosal inflammation. We propose that mucosal inflammation, by eliciting substantial and ongoing systemic DNA damage, contributes early on to genetic instability necessary for progression to inflammatory bowel disease–associated dysplasia and the development of cancer. [Cancer Res 2009;69(11):4827–34]