bluuebunny/crossref_metadata_2025 huggingface dataset:
Structure–Property Relationships and Nonlinear Optical Effects in Donor‐Substituted Dicyanopyrazine‐Derived Push–Pull Chromophores with Enlarged and Varied π‐Linkers
Authors: Bureš Filip , Čermáková Hana , Kulhánek Jiří , Ludwig Miroslav , Kuznik Wojciech , Kityk Iwan V. , Mikysek Tomáš , Růžička Aleš
Published: December 2011

Thirteen new, stable, push–pull systems featuring dimethylamino and pyrazine‐2,3‐dicarbonitrile moieties as the donor and acceptor, respectively, and systematically extended and varied π‐linkers were prepared and investigated. Evaluation of the measured UV/Vis spectra, electrochemical data (cyclic voltammetry, rotating disc voltammetry, and polarography), X‐ray data, and experimentally determined and calculated hyperpolarizability values enabled structure–property studies; these revealed some important structural features that affected the efficiency of intramolecular charge‐transfer and nonlinear optical properties in this class ofheterocyclic push–pull chromophores. The charge‐transfer transition was most significantly affected by structuralfeatures such as π‐linker length, chromophore planarity, and the number of 1,4‐phenylene/ethynylene subunits in the π‐linker.
Impaired survival of neural progenitor cells in dentate gyrus of adult mice lacking FMRP
Authors: Lazarov Orly , Demars Michael P. , Da Tommy Zhao Kai , Ali Haroon M. , Grauzas Vanessa , Kney Adam , Larson John
Published: December 2011

Fragile X syndrome (FXS) is the most common form of inherited intellectual disability in humans. Individuals affected with the disorder exhibit a deficiency of the fragile X mental retardation protein (FMRP), due to transcriptional silencing of the Fmr1 gene. It is widely accepted that learning deficits in FXS result from impaired synaptic function and/or plasticity in the brain. Interestingly, recent evidence suggests that conditional knockout of Fmr1 in neural progenitor cells in mice impairs hippocampal neurogenesis, which in turn contributes to learning impairments. To examine the nature of the neurogenic impairments and determine whether they impact the morphology of the dentate gyrus, we assessed the extent of neural progenitor cell proliferation, survival, and differentiation in older adult Fmr1 knockout mice. Here, we show that the number of fast‐proliferating cells in the subgranular layer of the dentate gyrus, as well as the subsequent survival of these cells, are dramatically reduced in Fmr1 knockout mice. In addition, the number of mature neurons in the granule layer of the dentate gyrus of these mice is significantly smaller than in wild type littermate controls, suggesting that impaired proliferation and survival of neural progenitor cells compromises the structure of the dentate gyrus. Impaired adult neurogenesis may underlie, at least in part, the learning deficits that characterize fragile X syndrome. © 2011 Wiley Periodicals, Inc.
Feedback regulation of the α2(1) collagen gene via the Mek–Erk signaling pathway
Authors: Dzobo Kevin , Leaner Virna D. , Parker M. Iqbal
Published: December 2011

The extracellular matrix (ECM) provides the microenvironment that is pivotal for cell growth, motility, attachment, and differentiation. Advances in cell culture techniques have led to the development of cell‐derived ECM model systems that are more reflective of the in vivo architecture of the ECM in tissue. In this study, a fibroblast‐derived ECM (fd‐ECM) was used to study the feedback regulation of type I collagen synthesis in fibroblasts. Fibroblasts plated on a preformed fd‐ECM showed a significant decrease in the production of type I collagen and pro‐α2(1) collagen mRNA compared to cells grown in the absence of a matrix. Function‐blocking antibodies showed that this downregulation of type I collagen gene expression is mediated via α2β1 integrin. The use of several kinase inhibitors and a dominant negative ras construct (N17Ras) showed that the matrix‐mediated downregulation of COL1A2 occurs via Ras‐dependent activation of the MEK/ERK signaling pathway. Deletion analysis of the COL1A2 promoter implicated the region between −375 and −107 as containing a potential matrix responsive element. The use of Sp1 siRNA demonstrated that Sp1 is an important mediator of this feedback inhibition. This study provides some new insights into the feedback regulation of COL1A2 gene expression. © IUBMB, IUBMB Life, 2011.
Allyl isothiocyanate as a potential inducer of paraoxonase‐1 ‐ studies in cultured hepatocytes and in mice
Authors: Schrader Charlotte , Graeser Anne‐Christin , Huebbe Patricia , Wagner Anika E. , Rimbach Gerald
Published: December 2011

In this study, we tested the ability of structure‐related isothiocyanates to induce the antiatherogenic enzyme paraoxonase‐1 (PON1) in cultured hepatocytes. Allyl isothiocyanate (AITC), phenylethyl isothiocyanate (PEITC), and sulforaphane (SFN), but not butyl isothiocyanate (BITC) resulted in dose‐dependent induction of PON1 transactivation in Huh7 cells in vitro. Induction of PON1 due to AITC was inhibited by the selective peroxisome proliferator‐activated receptor γ‐antagonist T0070907. AITC was used in a subsequent in vivo study in mice (n = 10 per group, Western‐type diet) to test its PON1 inducing activity. Unlike in cultured hepatocytes, AITC supplementation (15 mg/kg body weight) did not increase hepatic PON1 mRNA and protein levels in mice. Thus, it is suggested that AITC may be a potent inducer of PON1 in vitro, but not in mouse liver in vivo. © 2011 IUBMB, IUBMB Life,, 2011.
Protein monoubiquitination and polyubiquitination generate structural diversity to control distinct biological processes
Authors: Sadowski Martin , Suryadinata Randy , Tan Anthonius Ricardo , Roesley Siti Nur Ain , Sarcevic Boris
Published: December 2011

Ubiquitination involves the attachment of ubiquitin (Ub) to lysine residues on substrate proteins or itself, which can result in protein monoubiquitination or polyubiquitination. Polyubiquitination through different lysines (seven) or the N‐terminus of Ub can generate different protein‐Ub structures. These include monoubiquitinated proteins, polyubiqutinated proteins with homotypic chains through a particular lysine on Ub or mixed polyubiquitin chains generated by polymerization through different Ub lysines. The ability of the ubiquitination pathway to generate different protein‐Ub structures provides versatility of this pathway to target proteins to different fates. Protein ubiquitination is catalyzed by Ub‐conjugating and Ub‐ligase enzymes, with different combinations of these enzymes specifying the type of Ub modification on protein substrates. How Ub‐conjugating and Ub‐ligase enzymes generate this structural diversity is not clearly understood. In the current review, we discuss mechanisms utilized by the Ub‐conjugating and Ub‐ligase enzymes to generate structural diversity during protein ubiquitination, with a focus on recent mechanistic insights into protein monoubiquitination and polyubiquitination. © IUBMB, IUBMB Life, 2011.
Iκb‐ζ plays an important role in the ERK‐dependent dysregulation of malaria parasite GPI‐induced IL‐12 expression
Authors: Zhu Jianzhong , Weinberg Rebecca , Wu Xianzhu , Gowda Nagaraj M. , Muta Tatsushi , Gowda D. Channe
Published: December 2011

Plasmodium falciparum glycosylphosphatidylinositols (GPIs) have been proposed as malaria pathogenic factors based on their ability to induce proinflammatory responses in macrophages and malaria‐like symptoms in mice. Parasite GPIs induce the production of inflammatory cytokines by activating the mitogen‐activated protein kinase (MAPK) and NF‐κB signaling pathways. Importantly, inhibition of the extracellular‐signal‐regulated kinase (ERK) pathway upregulates a subset of cytokines, including IL‐12. We investigated the role of nuclear transcription factor, IκB‐ζ, in the GPI‐induced dysregulated expression of IL‐12 on inhibition of the ERK pathway. GPIs efficiently induced the expression of IκB‐ζ in macrophages regardless of whether cells were pretreated or untreated with ERK inhibitors, indicating that ERK has no role in IκB‐ζ expression. However, on ERK inhibition followed by stimulation with GPIs, NF‐κB binding to Il12b promoter κB site was markedly increased, suggesting that the ERK pathway regulates Il12b transcription. Knockdown of IκB‐ζ using siRNA markedly reduced the GPI‐induced IL‐12 production and abrogated the dysregulated IL‐12 production in ERK inhibited cells. Together these results demonstrate that ERK modulates IL‐12 expression by regulating IκB‐ζ‐dependent binding of NF‐κB transcription factors to Il12b gene promoter. Additionally, our finding that IκB‐ζ can be knocked down efficiently in primary macrophages is valuable for studies aimed at gaining further insights into IκB‐ζ function. © 2011 IUBMB, IUBMB Life,, 2012
Determination of pesticide residues in complex matrices using multi‐walled carbon nanotubes as reversed‐dispersive solid‐phase extraction sorbent
Authors: Zhao Pengyue , Wang Lei , Luo Jinhui , Li Jianguo , Pan Canping
Published: December 2011

A modified quick, easy, cheap, effective, rugged and safe (QuEChERS) method with multi‐walled carbon nanotubes (MWCNTs) as a reversed‐dispersive solid‐phase extraction (r‐DSPE) material combined with gas chromatography‐mass spectrometry was developed for the determination of 14 pesticides in complex matrices. Four vegetables (leek, onion, ginger and garlic) were selected as the complex matrices for validating this new method. This technique involved the acetonitrile‐based sample preparation and MWCNTs were used as the r‐DSPE material in the cleanup step. Two important parameters influencing the MWCNTs efficiency, the external diameters and the amount of MWCNTs used, were investigated. Under the optimized conditions, recoveries of 78–110% were obtained for the target analytes in the complex matrices at two concentration levels of 0.02 and 0.2 mg/kg. In addition, the RSD values ranged from 1 to 13%. LOQs and LODs for 14 pesticides ranged from 2 to 20 μg/kg and from 1 to 6 μg/kg, respectively.
A Hydrophobic Starch Polymer for Nanoparticle‐Mediated Delivery of Docetaxel
Authors: Dandekar Prajakta , Jain Ratnesh , Stauner Thomas , Loretz Brigitta , Koch Marcus , Wenz Gerhard , Lehr Claus‐Michael
Published: December 2011

A hydrophobic starch derivative is used for safe and enhanced delivery of anticancer agents. The synthesis and characterization of propyl starch with a controlled degree of substitution to modulate the release of the encapsulated hydrophobic drug is reported. The application of this polymer for formulating nanoparticles of docetaxel, an anti‐cancer agent effective against numerous types of cancers but possessing intrinsic formulation difficulties is described. The solvent emulsification/diffusion technique is used and the synthesis is optimized with respect to several formulation parameters. Uptake studies with these nanoparticles indicate their enhanced internalization by the cancerous cells and their peri‐nuclear localization.

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Statistical comparison of dynamic contrast‐enhanced MRI pharmacokinetic models in human breast cancer
Authors: Li Xia , Welch E. Brian , Chakravarthy A. Bapsi , Xu Lei , Arlinghaus Lori R. , Farley Jaime , Mayer Ingrid A. , Kelley Mark C. , Meszoely Ingrid M. , Means‐Powell Julie , Abramson Vandana G. , Grau Ana M. , Gore John C. , Yankeelov Thomas E.
Published: December 2011

By fitting dynamic contrast‐enhanced MRI data to an appropriate pharmacokinetic model, quantitative physiological parameters can be estimated. In this study, we compare four different models by applying four statistical measures to assess their ability to describe dynamic contrast‐enhanced MRI data obtained in 28 human breast cancer patient sets: the chi‐square test (χ2), Durbin–Watson statistic, Akaike information criterion, and Bayesian information criterion. The pharmacokinetic models include the fast exchange limit model with (FXL_vp) and without (FXL) a plasma component, and the fast and slow exchange regime models (FXR and SXR, respectively). The results show that the FXL_vp and FXR models yielded the smallest χ2 in 45.64 and 47.53% of the voxels, respectively; they also had the smallest number of voxels showing serial correlation with 0.71 and 2.33%, respectively. The Akaike information criterion indicated that the FXL_vp and FXR models were preferred in 42.84 and 46.59% of the voxels, respectively. The Bayesian information criterion also indicated the FXL_vp and FXR models were preferred in 39.39 and 45.25% of the voxels, respectively. Thus, these four metrics indicate that the FXL_vp and the FXR models provide the most complete statistical description of dynamic contrast‐enhanced MRI time courses for the patients selected in this study. Magn Reson Med, 2012. © 2011 Wiley Periodicals, Inc.
The altered expression of MiR‐221/‐222 and MiR‐23b/‐27b is associated with the development of human castration resistant prostate cancer
Authors: Sun Tong , Yang Ming , Chen Shaoyong , Balk Steven , Pomerantz Mark , Hsieh Chen‐Lin , Brown Myles , Lee Gwo‐Shu Mary , Kantoff Philip W.
Published: December 2011

BACKGROUND

We have previously identified seven miRs‐miR‐221, ‐222, ‐23b, ‐27b, ‐15a, ‐16‐1, and ‐203, that are differentially expressed in the hormone sensitive LNCaP cell line and the hormone resistant LNCaP‐abl cell line and hypothesized that these miRs may characterize certain subtypes of human castration resistant prostate cancer (CRPC).

METHODS

Functional studies in cell culture systems have been performed to determine the effect of alternated expression level on cellular response to androgen treatment. To determine the clinical relevance of the expression patterns of these miRs, we compared the expression levels of these seven miRs in normal prostate tissues from 86 individuals, prostate tumor tissues from 34 individuals with localized hormone naïve disease, and bone‐derived metastatic CRPC tissues from 17 individuals.

RESULTS

The altered expression of miR‐221/‐222 (as previously described) or miR‐203 affected the cellular response to androgen treatment, suggesting their potential involvement in the transition to CRPC. However, the expression of miR‐23b, ‐27b, ‐15a, and ‐16‐1 did not have a significant influence in the cellular response to androgen treatment, suggesting that these miRs may not play a causative role in the CRPC phenotype. Comparison of the expression levels of these miRs in tissue samples revealed that strikingly, ∼90% of the analyzed metastatic CRPC tumors could be characterized by the increased miR‐221/‐222 expression and the down‐regulated miR‐23b/‐27b expression.

CONCLUSIONS

This finding suggests that altered miR‐221/‐222 and miR‐23b/‐27b expression may be associated with the CRPC process. Prostate 72:1093–1103, 2012. © 2011 Wiley Periodicals, Inc.
Prospects in radionuclide imaging of prostate cancer
Authors: Lütje Susanne , Boerman Otto C. , van Rij Catharina M. , Sedelaar Michiel , Helfrich Wijnand , Oyen Wim J.G. , Mulders Peter F.A.
Published: December 2011

Prostate cancer is the most common malignancy in men in the Western world and represents a major health problem with substantial morbidity and mortality. Sensitivity and specificity of digital rectal examination (DRE) and evaluation of prostate specific antigen (PSA) are excellent methods for diagnosis of prostate cancer, but have limited value for staging. Imaging of prostate cancer has become increasingly important to improve staging and management of prostate cancer patients. Conventional imaging modalities, such as transrectal ultrasound and computed tomography, show limited accuracy for a reliable assessment of prostate cancer. Diagnostic value of magnetic resonance imaging has improved by dynamic contrast enhancement (DCI‐MRI) and diffusion‐weighted magnetic resonance imaging (DWI). Recently, substantial progress has been made in the development of functional and molecular imaging modalities, such as positron emission tomography using radiolabeled metabolic tracers, receptor‐binding ligands, amino acids, peptides, or antibodies. Here, we review the value of these novel radionuclide imaging techniques in the assessment of prostate cancer. Prostate 72:1262–1272, 2012. © 2011 Wiley Periodicals, Inc.
Opportunities for minimization of confounding in observational research
Authors: Quartey George , Feudjo‐Tepie Maurille , Wang Jixian , Kim Joseph
Published: December 2011

Observational epidemiological studies are increasingly used in pharmaceutical research to evaluate the safety and effectiveness of medicines. Such studies can complement findings from randomized clinical trials by involving larger and more generalizable patient populations by accruing greater durations of follow‐up and by representing what happens more typically in the clinical setting. However, the interpretation of exposure effects in observational studies is almost always complicated by non‐random exposure allocation, which can result in confounding and potentially lead to misleading conclusions. Confounding occurs when an extraneous factor, related to both the exposure and the outcome of interest, partly or entirely explains the relationship observed between the study exposure and the outcome. Although randomization can eliminate confounding by distributing all such extraneous factors equally across the levels of a given exposure, methods for dealing with confounding in observational studies include a careful choice of study design and the possible use of advanced analytical methods. The aim of this paper is to introduce some of the approaches that can be used to help minimize the impact of confounding in observational research to the reader working in the pharmaceutical industry. Copyright © 2011 John Wiley & Sons, Ltd.
Using a Learning Needs Assessment to Identify Knowledge Deficits Regarding Procedural Sedation for Pediatric Patients
Authors: Jest Anne D. , Tonge Andrea
Published: December 2011

Procedural sedation is a cost‐effective method of providing sedation and analgesia for patients undergoing diagnostic and therapeutic procedures. Sedation ranges on a continuum from minimal sedation to deep sedation, so procedural sedation can pose many risks for patients (eg, compromised airway, depressed respirations, hypotension). The unique variables inherent in the pediatric population and the associated risks of procedural sedation make it imperative that RNs be knowledgeable and competent in monitoring and managing these patients. Through the use of a learning needs assessment, perioperative resource nurses at a pediatric hospital in a large, southeast metropolitan area identified practice concerns associated with staff RNs' management of pediatric patients undergoing procedural sedation. As a result of these findings, the perioperative resource nurses are in the process of implementing annual sedation competency skills testing in a special procedures laboratory for all nurses who participate in sedation procedures.
Decision making after pediatric traumatic brain injury: trajectory of recovery and relationship to age and gender
Authors: Schmidt Adam T. , Hanten Gerri R. , Li Xiaoqi , Vasquez Ana C. , Wilde Elisabeth A. , Chapman Sandra B. , Levin Harvey S.
Published: December 2011

The aim of the study was to examine longitudinal patterns of decision making based on risk and reward using a modified version of the Iowa Gambling Task (IGT) in children who had sustained traumatic brain injury (TBI) and children with orthopedic injury (OI). Participants were 135 children and adolescents with TBI (n = 71) or OI (n = 64) who were 7–17 years at the time of injury were enrolled and assessed prospectively at baseline and at follow‐up intervals of 3, 12, 18, and 24 months after injury. Groups were similar in age, socioeconomic status, and gender. Participants chose from four decks of cards with the aim of maximizing earnings across 100 trials. Two of the decks offered relatively small rewards and relatively small losses, but were advantageous over the course of the experiment. The other two decks offered large rewards, but also introduced occasional large losses, and were considered disadvantageous over the course of the experiment. The variable of interest was the proportion of advantageous decks chosen across trials.

Longitudinal analysis of the pattern of change across 2 years revealed a three‐way interaction among injury group, age, and the quadratic term of interval‐since‐injury. In this interaction, the effect of age weakened in the TBI group across time, as compared to the OI group, which showed stronger quadratic patterns across the recovery intervals that differed by age. The OI group generally outperformed the TBI group.

In addition, analyses revealed a three‐way interaction among group, gender and the cubic term of post‐injury interval, such that overall, males improved a great deal with time, but females showed small gains, regardless of injury group.
WEAK FORMS OF AMENABILITY FOR BANACH ALGEBRAS
Authors: SAMEA H.
Published: December 2011

In this paper, the amenability and approximate amenability of weighted ℓp-direct sums of Banach algebras with unit, where 1≤p<∞, are completely characterized. Applications to compact groups and hypergroups are given.
UNIQUENESS OF ENTIRE FUNCTIONS SHARING A VALUE WITH LINEAR DIFFERENTIAL POLYNOMIALS
Authors: LAHIRI INDRAJIT , MUKHERJEE RAJIB
Published: December 2011

We study the uniqueness of entire functions sharing a nonzero finite value with linear differential polynomials and improve a result of P. Li.
BIHARMONIC SUBMANIFOLDS IN NONFLAT LORENTZ 3-SPACE FORMS
Authors: SASAHARA TORU
Published: December 2011

The purpose of this paper is to classify nonharmonic biharmonic curves and surfaces in de Sitter 3-space and anti-de Sitter 3-space.
Genetic variability and demographic history ofHeliothis virescens(Lepidoptera: Noctuidae) populations from Brazil inferred by mtDNA sequences
Authors: Albernaz K.C. , Silva-Brandão K.L. , Fresia P. , Cônsoli F.L. , Omoto C.
Published: December 2011

Intra- and inter-population genetic variability and the demographic history ofHeliothis virescens(F.) populations were evaluated by using mtDNA markers (coxI, coxIIandnad6) with samples from the major cotton- and soybean-producing regions in Brazil in the growing seasons 2007/08, 2008/09 and 2009/10. AMOVA indicated low and non-significant genetic structure, regardless of geographical scale, growing season or crop, with most of genetic variation occurring within populations. Clustering analyzes also indicated low genetic differentiation. The haplotype network obtained with combined datasets resulted in 35 haplotypes, with 28 exclusive occurrences, four of them sampled only from soybean fields. The minimum spanning network showed star-shaped structures typical of populations that underwent a recent demographic expansion. The recent expansion was supported by other demographic analyzes, such as the Bayesian skyline plot, the unimodal distribution of paired differences among mitochondrial sequences, and negative and significant values of neutrality tests for the Tajima'sDand Fu'sFSparameters. In addition, high values of haplotype diversity (Ĥ) and low values of nucleotide diversity (π), combined with a high number of low frequency haplotypes and values of θπ<θW, suggested a recent demographic expansion ofH. virescenspopulations in Brazil. This demographic event could be responsible for the low genetic structure currently found; however, haplotypes present uniquely at the same geographic regions and from one specific host plant suggest an initial differentiation amongH. virescenspopulations within Brazil.
Effect of polymorphisms in the leptin, leptin receptor and acyl-CoA:diacylglycerol acyltransferase 1 (DGAT1) genes and genetic polymorphism of milk proteins on bovine milk composition
Authors: Glantz Maria , Lindmark Månsson Helena , Stålhammar Hans , Paulsson Marie
Published: December 2011

The relations between cow genetics and milk composition have gained a lot of attention during the past years, however, generally only a few compositional traits have been examined. The aim of this study was to determine if polymorphisms in the leptin (LEP), leptin receptor (LEPR) and acyl-CoA:diacylglycerol acyltransferase 1 (DGAT1) genes as well as genetic polymorphism of β-casein (β-CN), κ-CN and β-lactoglobulin (β-LG) impact several bovine milk composition traits. Individual milk samples from the Swedish Red and Swedish Holstein breeds were analyzed for components in the protein, lipid, carbohydrate and mineral profiles. Cow alleles were determined on the following SNP: A1457G, A252T, A59V and C963T on the LEP gene, T945M on the LEPR gene and Nt984+8(A-G) on the DGAT1 gene. Additionally, genetic variants of β-CN, κ-CN and β-LG were determined. For both the breeds, the same tendency of minor allele frequency was found for all SNPs and protein genes, except on LEPA1457G and LEPC963T. This study indicated significant (P<0·05) associations between the studied SNPs and several compositional parameters. Protein content was influenced by LEPA1457G (G>A) and LEPC963T (T>C), whereas total Ca, ionic Ca concentration and milk pH were affected by LEPA1457G, LEPA59V, LEPC963T and LEPRT945M. However, yields of milk, protein, CN, lactose, total Ca and P were mainly affected by β-CN (A2>A1) and κ-CN (A>B>E). β-LG was mainly associated with whey protein yield and ionic Ca concentration (A>B). Thus, this study shows possibilities of using these polymorphisms as markers within genetic selection programs to improve and adjust several compositional parameters.
A twin study of body dysmorphic concerns
Authors: Monzani B. , Rijsdijk F. , Anson M. , Iervolino A. C. , Cherkas L. , Spector T. , Mataix-Cols D.
Published: December 2011

Background

Dysmorphic concern refers to an excessive preoccupation with a perceived or slight defect in physical appearance. It lies on a continuum of severity from no or minimal concerns to severe concerns over one's appearance. The present study examined the heritability of dysmorphic concerns in a large sample of twins.

Method

Twins from the St Thomas UK twin registry completed a valid and reliable self-report measure of dysmorphic concerns, which also includes questions about perceived body odour and malfunction. Twin modelling methods (female twins only, n=3544) were employed to decompose the variance in the liability to dysmorphic concerns into additive genetic, shared and non-shared environmental factors.

Results

Model-fitting analyses showed that genetic factors accounted for approximately 44% [95% confidence intervals (CI) 36–50%] of the variance in dysmorphic concerns, with non-shared environmental factors and measurement error accounting for the remaining variance (56%; 95% CI 50–63%). Shared environmental factors were negligible. The results remained unchanged when excluding individuals reporting an objective medical condition/injury accounting for their concern in physical appearance.

Conclusions

Over-concern with a perceived or slight defect in physical appearance is a heritable trait, with non-shared environmental factors also playing an important role in its causation. The results are relevant for various psychiatric disorders characterized by excessive concerns in body appearance, odour or function, including but not limited to body dysmorphic disorder.
Exactness of the Euclidean algorithm and of the Rauzy induction on the space of interval exchange transformations
Authors: MIERNOWSKI TOMASZ , NOGUEIRA ARNALDO
Published: December 2011

The two-dimensional homogeneous Euclidean algorithm is the central motivation for the definition of the classical multidimensional continued fraction algorithms, such as Jacobi–Perron, Poincaré, Brun and Selmer algorithms. The Rauzy induction, a generalization of the Euclidean algorithm, is a key tool in the study of interval exchange transformations. Both maps are known to be dissipative and ergodic with respect to Lebesgue measure. Here we prove that they are exact.
Reconstructing desecuritisation: the normative-political in the Copenhagen School and directions for how to apply it
Authors: HANSEN LENE
Published: December 2011

The concept of desecuritisation – the move of an issue out of the sphere of security – has been the subject of heated international political theory debate and adopted in case studies across a range of sectors and settings. What unites the political theory and the applied literature is a concern with the normative-political potential of desecuritisation. This article documents the political status and content of desecuritisation through four readings: one which shows how desecuritisation is a Derridarian supplement to the political concept of securitisation; one which traces the understanding of the public sphere's ability to rework the friend-enemy distinction; one which emphasises the role of choice, responsibility, and decisions; and one which uncovers the significance of the historical context of Cold War détente. The last part of the article provides a reading of the varied use of desecuritisation in applied analysis and shows how these can be seen as falling into four forms of desecuritisation. Each of the latter identifies a distinct ontological position as well as a set of more specific political and normative questions.
The epidemiology of human salmonellosis in New Zealand, 1997–2008
Authors: LAL A. , BAKER M. G. , FRENCH N. P. , DUFOUR M. , HALES S.
Published: December 2011

This study describes the epidemiology of human salmonellosis in New Zealand using notified, hospitalized and fatal cases over a 12-year period (1997–2008). The average annual incidence for notifications was 42·8/100 000 population and 3·6/100 000 population for hospitalizations. Incidence was about twice as high in summer as in winter. Rural areas had higher rates than urban areas (rate ratio 1·23, 95% confidence interval 1·22–1·24 for notifications) and a distinct spring peak. Incidence was highest in the 0–4 years age group (154·2 notifications/100 000 and 11·3 hospitalizations/100 000). Hospitalizations showed higher rates for Māori and Pacific Island populations compared to Europeans, and those living in more deprived areas, whereas notifications showed the reverse, implying that notifications are influenced by health-seeking behaviours.SalmonellaTyphimurium was the dominant serotype followed byS. Enteritidis. For a developed country, salmonellosis rates in New Zealand have remained consistently high suggesting more work is needed to investigate, control and prevent this disease.
Tissue Distribution of S‐(2‐Succino)cysteine (2SC), a Biomarker of Mitochondrial Stress in Obesity and Diabetes
Authors: Thomas Sonia A. , Storey Kenneth B. , Baynes John W. , Frizzell Norma
Published: December 2011

S‐(2‐succino)cysteine (2SC) is a chemical modification of proteins produced by reaction of fumarate with thiol groups in protein, a process known as succination. We propose to use the name S‐(2‐succino)cysteine (instead of S‐(2‐succinyl)cysteine) from this point on. This is to distinguish protein succination (in which fumarate forms a thioether linkage with cysteine residues) from succinylation (in which an ester, thioester or amide bond would be formed). Succination of proteins is increased in muscle of type 1 diabetic rats and in adipose tissue in type 2 diabetic mice. The increase in 2SC is a direct result of tissue accumulation of fumarate in response to nutrient excess and resultant mitochondrial stress in diabetes. In this study, we examine the breadth of succination of tissue proteins in the db/db type 2 model of diabetes. We also determined the extent of succination in epididymal adipocytes of type 1 (Akita, streptozotocin (STZ)) and type 2 (ob/ob, db/db) diabetic mice, in diet‐induced obese (DIO) mice, and in the adipose tissue of ground squirrels in various stages of hibernation. While succination was not increased in most tissues (brain, heart, kidney, liver, skeletal muscle) in the db/db model of diabetes, it was increased in all adipose beds of type 2 diabetic and DIO mice in comparison to their controls. Succination was not increased in adipocytes of type 1 diabetic mice. Adipose tissue from hibernating (HIB) 13‐lined ground squirrels was also studied to determine if obesity in the absence of hyperglycemia affected succination of proteins. There were no differences in succination of proteins in brown or white adipose tissue over the torpor‐arousal cycle. We conclude that 2SC is a biomarker of nutrient excess and mitochondrial stress in adipose tissue, increasing under the hyperglycemic and insulin resistant conditions associated with type 2 diabetes and obesity.
A proteomics approach to the study of the molecular consequence of IgE‐mediated cell signalling in RBL‐2H3.1 cells and 2D reference map preparation for the RBL‐2H3.1 cell line
Authors: Sadroddiny Esmaeil , Moir Arthur J G , Helm Birgit A
Published: December 2011

A highly reproducible 2D (two‐dimensional) map for the proteome and a pattern of protein phosphorylation of high secretory variant of RBL‐2H3 cells (RBL‐2H3.1) (a model cell in allergy studies) in resting and treated cells with IgE or IgE+Ag are presented. Major molecular changes were seen in the proteome of 3 h‐activated cells with IgE+Ag, especially for proteins of ∼17 kDa compared with the control. We have identified 13 proteins on 11 corresponding spots as up‐regulated proteins in response to IgE+Ag activation. Also, protein identification on 55 spots with MALDI—TOF (matrix‐assisted laser‐desorption ionization—time‐of‐flight) and ESI‐MS (electrospray ionization mass spectrometry) resulted in a reliable 2D reference map and an opportunity for the subsequent use of a 1 min‐activated cell map for a phosphoproteomics study.
Refined tip preparation by electrochemical etching and ultrahigh vacuum treatment to obtain atomically sharp tips for scanning tunneling microscope and atomic force microscope
Authors: Hagedorn Till , Ouali Mehdi El , Paul William , Oliver David , Miyahara Yoichi , Grütter Peter
Published: December 2011

A modification of the common electrochemical etching setup is presented. The described method reproducibly yields sharp tungsten tips for usage in the scanning tunneling microscope and tuning fork atomic force microscope. In situ treatment under ultrahigh vacuum (p ⩽10−10 mbar) conditions for cleaning and fine sharpening with minimal blunting is described. The structure of the microscopic apex of these tips is atomically resolved with field ion microscopy and cross checked with field emission.
Continuous distribution model for the investigation of complex molecular architectures near interfaces with scattering techniques
Authors: Shekhar Prabhanshu , Nanda Hirsh , Lösche Mathias , Heinrich Frank
Published: December 2011

Biological membranes are composed of a thermally disordered lipid matrix and therefore require non-crystallographic scattering approaches for structural characterization with x-rays or neutrons. Here we develop a continuous distribution (CD) model to refine neutron or x-ray reflectivity data from complex architectures of organic molecules. The new model is a flexible implementation of the composition-space refinement of interfacial structures to constrain the resulting scattering length density profiles. We show this model increases the precision with which molecular components may be localized within a sample, with a minimal use of free model parameters. We validate the new model by parameterizing all-atom molecular dynamics (MD) simulations of bilayers and by evaluating the neutron reflectivity of a phospholipid bilayer physisorbed to a solid support. The determination of the structural arrangement of a sparsely-tethered bilayer lipid membrane (stBLM) comprised of a multi-component phospholipid bilayer anchored to a gold substrate by a thiolated oligo(ethylene oxide) linker is also demonstrated. From the model we extract the bilayer composition and density of tether points, information which was previously inaccessible for stBLM systems. The new modeling strategy has been implemented into the ga_refl reflectivity data evaluation suite, available through the National Institute of Standards and Technology (NIST) Center for Neutron Research (NCNR).
Interfaces in organic devices studied with resonant soft x-ray reflectivity
Authors: Yan Hongping , Wang Cheng , Garcia Andres , Swaraj Sufal , Gu Ziran , McNeill Christopher R. , Schuettfort Torben , Sohn Karen E. , Kramer Edward J. , Bazan Guillermo C. , Nguyen Thuc-Quyen , Ade Harald
Published: December 2011

Interfaces between donor and acceptor semiconducting polymers are critical to the performance of polymer light-emitting diodes and organic solar cells. Similarly, interfaces between a conjugated polymer and a dielectric play a critical role in organic thin-film transistors. Often, these interfaces are difficult to characterize with conventional methods. Resonant soft x-ray reflectivity (R-SoXR) is a unique and relatively simple method to investigate such interfaces. R-SoXR capabilities are exemplified by presenting or discussing results from systems spanning all three device categories. We also demonstrate that the interfacial widths between active layers can be controlled by annealing at elevated temperature, pre-annealing of the bottom layer, or casting from different solvent mixtures. The extension of R-SoXR to the fluorine K absorption edge near 698 eV is also demonstrated.
Ducted kinetic Alfvén waves in plasma with steep density gradients
Authors: Houshmandyar Saeid , Scime Earl E.
Published: December 2011

Given their high plasma density (n ∼ 1013 cm−3), it is theoretically possible to excite Alfvén waves in a conventional, moderate length (L ∼ 2 m) helicon plasma source. However, helicon plasmas are decidedly inhomogeneous, having a steep radial density gradient, and typically have a significant background neutral pressure. The inhomogeneity introduces regions of kinetic and inertial Alfvén wave propagation. Ion-neutral and electron-neutral collisions alter the Alfvén wave dispersion characteristics. Here, we present the measurements of propagating kinetic Alfvén waves in helium helicon plasma. The measured wave dispersion is well fit with a kinetic model that includes the effects of ion-neutral damping and that assumes the high density plasma core defines the radial extent of the wave propagation region. The measured wave amplitude versus plasma radius is consistent with the pile up of wave magnetic energy at the boundary between the kinetic and inertial regime regions.
Rectifying characteristic of perovskite oxide La1.89Ce.11CuO4/Ba.5Sr.5TiO3/La.67Sr.33MnO3 heterostructures
Authors: Xia F. J. , Fu Y. J. , Yuan J. , Wu H. , Xie Z. , Xu B. , Cao L. X. , Zhao B. R. , Zhu B. Y.
Published: December 2011

Heterostructure composed of electron-doped high-Tc superconductor La1.89Ce0.11CuO4 (LCCO), ferroelectric Ba0.5Sr0.5TiO3 (BST) and colossal magnetoresistance (CMR) La0.67Sr0.33MnO3 (LSMO) thin films were deposited on the (001) SrTiO3 (STO) substrate by pulsed laser deposition method. The current-voltage measurement shows that the LCCO/BST/LSMO structure has strong rectification comparing to the LCCO/LSMO, LCCO/BST and BST/LSMO bilayer structures. The experiment indicates that both the BST and LCCO layers play important roles in the rectifying effect in the oxide heterostructures. We discuss the mechanism of their rectification based on the energy band bending as well as the depletion and the diffusion of the charge carriers at the interfaces. The growth conditions and the multilayer features as well as the properties of individual material in the heterostructures were also investigated.
Dielectric relaxation in hafnium oxide: A study of transient currents and admittance spectroscopy in HfO2 metal-insulator-metal devices
Authors: Mannequin C. , Gonon P. , Vallée C. , Bsiesy A. , Grampeix H. , Jousseaume V.
Published: December 2011

Dielectric relaxation is studied in 10 nm HfO2 thin films which are deposited by atomic layer deposition on TiN and Pt electrodes. Transient currents are recorded from 10−3 s to 10 s, as a function of bias (0.1 V to 1 V) and temperature (20 °C to 180 °C). A Curie-von Schweidler law is observed, I = Q0/tα. The power law exponent α is constant with bias and strongly depends on the temperature (varying in the 0.65–1.05 range, with a peak at 75 °C). The amplitude Q0 is described by a relation of the form Q0 = C0Vβ, where the factor C0 is weakly activated and the exponent β varies with temperature (in the 0.9–1.5 range as T varies). Transient currents are discussed along with tunneling based models from the literature. To complement transient current experiments, admittance spectroscopy (conductance G and capacitance C) is performed at low frequencies, from 0.01 Hz to 10 kHz. The dispersion law of the conductance is of the form G ∼ ωs. The capacitance is the sum of two terms, a non-dispersive term (C∞) and a low-frequency dispersive term, CLF ∼ ω−n. The critical exponents s and n verify s ≈ α and n ≈ 1−α. At room temperature, the dielectric constant is expressed as ɛ′ = Δɛ′ f−n + ɛ′∞, where ɛ′∞ = 11.1, n ≈ 0.2/0.3 (Pt/TiN), and Δɛ′ ≈ 1.5/0.7 (Pt/TiN).
Conducting nanofilaments formed by oxygen vacancy migration in Ti/TiO2/TiN/MgO memristive device
Authors: Lv Qibiao , Wu Shuxiang , Lu Jingquan , Yang Mei , Hu Ping , Li Shuwei
Published: December 2011

High-quality TiN and TiO2 thin films were grown on MgO(100) substrate by plasma-assisted molecule beam epitaxy. X-ray photoelectron spectroscopy and x-ray diffraction studies indicate that the films are single phase. The memory cell composed of Ti/TiO2/TiN/MgO showed a bistable bipolar resistive switching behavior with either electrode grounded. The nature of the bipolar resistive switching phenomenon could derive from the formation and annihilation of filaments induced by oxygen vacancy and oxygen ion migration near/at the bias-applied electrode. In addition, a simple calculation of the filamentary resistivity in model might indicate that different devices made by TiO2 thin films with different phases might share the similar resistive switching mechanism.
Performance-improved nonvolatile memory with aluminum nanocrystals embedded in Al2O3 for high temperature applications
Authors: Xu Zhongguang , Huo Zongliang , Zhu Chenxin , Cui Yanxiang , Wang Ming , Zheng Zhiwei , Liu Jing , Wang Yumei , Li Fanghua , Liu Ming
Published: December 2011

In this paper, we demonstrate a charge trapping memory with aluminum nanocrystals (Al- NCs) embedded in Al2O3 high-k dielectric. Compared to metal/Al2O3/SiO2/Si structure, this device exhibits a larger memory window (6.7 V at ±12 V), faster program/erase speed and good endurance. In particular, data retention is improved greatly both at room temperature and in high-temperature (up to 150 °C). The results indicate that the device with the embedding Al-NCs in Al2O3 film has a strong potential for future high-performance nonvolatile memory application.
Hydrogenation and surface density changes in hydrocarbon films during erosion using Ar/H2 plasmas
Authors: Fox-Lyon N. , Oehrlein G. S. , Ning N. , Graves D. B.
Published: December 2011

We report interactions of low pressure Ar, H2, and Ar/H2 mixture plasmas with a-C:H films. Surface evolution and erosion of a-C:H films were examined for ion energies up to 200 eV by rf biasing the substrates. Film surfaces were characterized using in situ ellipsometry, x-ray photoelectron spectroscopy, and atomic force microscopy. Multilayer models for steady-state modified surface layers are constructed using ellipsometric data and compared with results of molecular dynamics (MD) simulations and transport of ions in matter (TRIM) calculations. We find that Ar plasma causes a modified layer at the surface that is depleted of H atoms. The depth and degree of this modification is strongly depending on Ar ion energies. This depletion saturates quickly during plasma exposure (<1 s) and persists during steady-state erosion. We find that the thickness and density of the H-depleted layer are in good agreement with MD and TRIM simulations. The degree of surface densification decreases when small amounts of H2 are added to Ar plasmas. When more than 5% H2 is added to the plasma, long term loss in surface density is observed, indicating rehydrogenation and saturation of H in the film. As the H2 fraction increases, the near-surface atomic H increases and the ion composition bombarding the surface changes. This causes incorporation of H deeper into the a-C:H film. For a-C:H films exposed to pure H2 plasmas, H is introduced into the near-surface region to a depth of up to ∼8 nm from the surface. As the rf bias is increased the ion energy transitions from solely chemical sputtering to one involving physical sputtering, causing the yield of C atoms from the surface to greatly increase. The increasing yield suppresses H incorporation/saturation and decreases the magnitude of the modified surface layer.
Optical trapping by a metal thin-film edge
Authors: Li Dongxiao , Xi Yonggang , Koo Kim Hong
Published: December 2011

We present a new method of optical trapping based on the intensity gradient that is created by boundary diffraction of light at a metal thin-film edge. The structure consists of an optically thick metal-film step formed on a semi-transparent thin-film-metal-coated glass substrate. While the underlying thin layer of metal serves the purpose of suppressing the thermophoretic effect, the metal film step is found to induce a highly localized intensity distribution of light around the edge via self-interference of an incident wave and its boundary diffraction wave. Two-dimensional (2D) optical trapping of micron-sized dielectric particles is experimentally demonstrated with a 100-nm-thick Au film edge formed on a 10-nm-thick-Cr-coated glass slide. For a 2-µm polystyrene sphere, ∼2-pN trapping force is measured at 30-mW incident power of a 1064-nm laser beam. Not involving surface plasmon fields, this thin-film edge trapping is polarization independent and can be easily incorporated into an on-chip microfluidic configuration.
Dynamical systems defining Jacobi's ϑ-constants
Authors: Brezhnev Yurii V. , Lyakhovich Simon L. , Sharapov Alexey A.
Published: December 2011

We propose a system of equations that defines Weierstrass–Jacobi's eta- and theta-constant series in a differentially closed way. This system is shown to have a direct relationship to a little-known dynamical system obtained by Jacobi. The classically known differential equations by Darboux–Halphen, Chazy, and Ramanujan are the differential consequences or reductions of these systems. The proposed system is shown to admit the Lagrangian, Hamiltonian, and Nambu formulations. We explicitly construct a pencil of nonlinear Poisson brackets and complete set of involutive conserved quantities. As byproducts of the theory, we exemplify conserved quantities for the Ramamani dynamical system and quadratic system of Halphen–Brioschi.
Constructing a new closure theory based on the third-order Ornstein-Zernike equation and a study of the adsorption of simple fluids
Authors: Lee Lloyd L.
Published: December 2011

The third-order Ornstein-Zernike equation (OZ3) is used in the construction of a bridge functional that improves over conventional liquid-theory closures (for example, the hypernetted chain or the Percus-Yevick equations). The OZ3 connects the triplet direct correlation C(3) to the triplet total correlation h(3). By invoking the convolution approximation of Jackson and Feenberg, we are able to express the third-order bridge function B3 as a functional of the indirect correlation γ. The resulting expression is generalized to higher-order bridge terms. This new closure is tested on the adsorption of Lennard-Jones fluid on planar hard surfaces by calculating the density profiles and comparing with Monte Carlo simulations. Particular attention is paid to the cases where molecular depletion on the substrate is evident. The results prove to be highly accurate and improve over conventional closures.