bluuebunny/crossref_metadata_2025 huggingface dataset:
Parental responsiveness moderates the association between early-life stress and reduced telomere length
Authors: Asok A. , Bernard K. , Roth T. L. , Rosen J. B. , Dozier M.
Published: March 2013

Early-life stress, such as maltreatment, institutionalization, and exposure to violence, is associated with accelerated telomere shortening. Telomere shortening may thus represent a biomarker of early adversity. Previous studies have suggested that responsive parenting may protect children from the negative biological and behavioral consequences of early adversity. This study examined the role of parental responsiveness in buffering children from telomere shortening following experiences of early-life stress. We found that high-risk children had significantly shorter telomeres than low-risk children, controlling for household income, birth weight, gender, and minority status. Further, parental responsiveness moderated the association between risk and telomere length, with more responsive parenting associated with longer telomeres only among high-risk children. These findings suggest that responsive parenting may have protective benefits on telomere shortening for young children exposed to early-life stress. Therefore, this study has important implications for early parenting interventions.
Healthscaping a medieval city: Lucca'sCuria viarumand the future of public health history
Authors: GELTNER G.
Published: March 2013

In early fourteenth-century Lucca, one government organ began expanding its activities beyond the maintenance of public works to promoting public hygiene and safety, and in ways that suggest both a concern for and an appreciation of population-level preventative healthcare. Evidence for this shift (which is traceable in and beyond the Italian peninsula) is mostly found in documents of practice such as court and financial records, which augment and complicate the traditional view afforded by urban statutes and medical treatises. The revised if still nebulous picture emerging from this preliminary study challenges a lingering tendency among urban and public health historians to see pre-modern European cities as ignorant andapatheticdemographic black holes.
‘The Open Work’: Ecologies of participation
Authors: Harries Guy
Published: March 2013

Audience engagement with a sound work can extend beyond fixed conventions in which roles of creation and reception are separate. In an ‘open work’ these roles are blurred, and the audience takes on an active part of co-creation. Participatory sound works can be considered as ecologies of engagement rather than fixed compositions. Technologies of dissemination and interactivity have become part of the design of such ecologies, and sound artists have integrated them in highly diverse works. Two main aspects of participatory ecologies will be considered: the continuum of ‘active interpretation’ to ‘co-authorship’ and the creation of a community of intersubjectivity. These two aspects will be discussed in the context of a range of sound works, including the author's workShadowgraphs(2009/11) and its interconnected manifestations: an installation, a live performance and a blog.
Understanding Interpretation, Informing Composition: audience involvement in aesthetic result
Authors: Hill Andrew
Published: March 2013

This paper documents elements of a research project undertaken between 2008 and 2012. Building upon the Intention/Reception project of Leigh Landy (2006) and Rob Weale (2005), the project sought to investigate audience interpretations for works of electroacoustic audiovisual music and to utilise an expanded understanding of the audience – as active participants in interpretation – to subsequently inform the composition of new works. This project combined three distinct research methodologies: empirical data collection, scholarly research and composition. The composed works were both informed by the results of empirical data collection and scholarly research, and adapted (re-composed) throughout the latter stages of the research in order to explore emergent research findings and research hypotheses.

Interpretations were demonstrated to be contingent upon the individual lived experience of an audience member, with aspects of the work's discourse acting to narrow the interpretative potential of the work. The use of mimetic materials (sonic or visual) within works of electroacoustic audiovisual music were demonstrated to be potentially obstructing to an aesthetic interpretation of the work. And the importance of recognising the distinction between physical signal and perceived object was highlighted within the process of composition and the subsequent testing.
Object and action naming in Russian- and German-speaking monolingual and bilingual children
Authors: KLASSERT ANNEGRET , GAGARINA NATALIA , KAUSCHKE CHRISTINA
Published: March 2013

The present study investigates the influence of word category on naming performance in two populations: bilingual and monolingual children. The question is whether and, if so, to what extent monolingual and bilingual children differ with respect to noun and verb naming and whether a noun bias exists in the lexical abilities of bilingual children. Picture naming of objects and actions by Russian–German bilingual children (aged 4–7 years) was compared to age-matched monolingual children. The results clearly demonstrate a naming deficit of bilingual children in comparison to monolingual children that increases with age. Noun learning is more fragile in bilingual contexts than is verb learning. In bilingual language acquisition, nouns do not predominate over verbs as much as is seen in monolingual German and Russian children. The results are discussed with respect to semantic-conceptual aspects and language-specific features of nouns and verbs, and the impact of input on the acquisition of these word categories.
Associations of parental feeding styles with child snacking behaviour and weight in the context of general parenting
Authors: Rodenburg Gerda , Kremers Stef PJ , Oenema Anke , van de Mheen Dike
Published: March 2013

Objective

To examine cross-sectional and longitudinal (one-year follow-up) associations of parental feeding styles with child snacking behaviour and weight in the context of general parenting, taking into account the multidimensionality of the controlling feeding style.

Design

Linear regression analyses were performed. Parents completed a questionnaire to measure five feeding style dimensions (Instrumental Feeding, Emotional Feeding, Encouragement, Overt Control and Covert Control) and children's fruit, energy-dense snack and sugar-sweetened beverage (SSB) intakes. Children's height and weight were measured to calculate their BMIZ-scores. Moderation by parenting style was tested by adding interaction terms to the regression analyses.

Setting

Observational study in the Netherlands.

Subjects

Parent–child dyads (n1275) participating in the INPACT (IVO Nutrition and Physical Activity Child cohorT) study; children were (on average) 9 years of age.

Results

Instrumental Feeding and Emotional Feeding were negatively related to child fruit intake one year later and positively to (changes in) child energy-dense snack intake. Encouragement was negatively related to child energy-dense snacking and SSB intake one year later. Overt Control was cross-sectionally and prospectively related to (changes in) child energy-dense snacking and SSB intake in a negative direction. Covert Control showed similar associations with child energy-dense snacking and SSB intake as Overt Control. Although Covert Control was also positively related to child fruit intake and (changes in) child BMIZ-score, bootstrapping analyses revealed only a differential effect of Overt Control and Covert Control on child BMIZ-score one year later, with Covert Control displaying a stronger, positive association. Moderation analyses showed that some significant associations between parental feeding styles and outcome measures were dependent on the degree of psychological control and behavioural control.

Conclusions

Instrumental Feeding and Emotional Feeding may have a detrimental impact on children's snacking behaviour, while Encouragement, Overt Control and Covert Control may lead to less energy-dense snacking and less SSB intake. Overt Control and Covert Control have differential effects on child BMIZ-score one year later, which supports the idea that they should be treated as separate constructs. Prospective studies with a longer follow-up may elucidate the causal pathways between the various feeding styles and children's snacking behaviour and weight, as well as the moderating influences of psychological and behavioural control.
ON EXISTENTIAL DECLARATIONS OF INDEPENDENCE IN IF LOGIC
Authors: BARBERO FAUSTO
Published: March 2013

We analyze the behaviour of declarations of independence between existential quantifiers in quantifier prefixes of Independence-Friendly (IF) sentences; we give a syntactical criterion to decide whether a sentence beginning with such prefix exists, such that its truth values may be affected by removal of the declaration of independence. We extend the result also to equilibrium semantics values for undetermined IF sentences.

The main theorem defines a schema of sound and recursive inference rules; we show more explicitly what happens for some simple special classes of sentences.

In the last section, we extend the main result beyond the scope of prenex sentences, in order to give a proof of the fact that the fragment of IF sentences with knowledge memory has only first-order expressive power.
Molecular orientation of Factor VIIIa on the phospholipid membrane surface determined by fluorescence resonance energy transfer
Authors: Wakabayashi Hironao , Fay Philip J.
Published: March 2013

F (Factor) VIIIa binds to phospholipid membranes during formation of the FXase complex. Free thiols from cysteine residues of isolated FVIIIa A1 and A2 subunits and the A3 domain of the A3C1C2 subunit were labelled with PyMPO maleimide {1-(2-maleimidylethyl)-4-[5-(4-methoxyphenyl)-oxazol-2-yl]pyridinium methanesulfonate} or fluorescein (fluorescence donors). Double mutations of the A3 domain (C2000S/T1872C and C2000S/D1828C) were also produced to utilize Cys1828 and Cys1872 residues for labelling. Labelled subunits were reacted with complementary non-labelled subunits to reconstitute FVIIIa. Octadecylrhodamine incorporated into phospholipid vesicles was used as an acceptor for distance measurements between FVIII residues and membrane surface by fluorescence resonance energy transfer. The results of the present study indicate that a FVIII axis on a plane that intersects the approximate centre of each domain is orientated with a tilt angle of ~30–50° on the membrane surface. This orientation predicted the existence of contacts mediated by residues 1713–1725 in the A3 domain in addition to a large area of contacts within the C domains. FVIII variants where Arg1719 or Arg1721 were mutated to aspartate showed a >40-fold reduction in membrane affinity. These results identify possible orientations for FVIIIa bound to the membrane surface and support a new interaction between the A3 domain and the membrane probably mediated in part by Arg1719 and Arg1721.
Traitements très précoces, précoces ou bien expectative armée ?
Réflexion à partir du suivi d’un cas de classe III avec excès vertical
Authors: Faure Jacques
Published: March 2013

Le débat sur la date optimale de prise en charge d’une dysmorphie maxillo-faciale est
loin d’être clos, les choix possibles sont le traitement très précoce avant la denture
mixte, pendant la petite enfance; seulement en denture mixte stable; seulement en denture
adulte complète; en croissance achevée ou quasi-achevée. Les options d’intervention
précoce sont pénalisées par la difficulté d’un diagnostic à poser très tôt (parfois
impossible à porter en l’absence de tout signe d’appel annonçant une très forte dysmorphie
évolutive), la difficulté d’un pronostic à long terme toujours imprécis, l’insuffisante de
la maturité psychologique requise, le manque de moyens d’ancrage, la nécessité de toutes
façons d’un traitement en deux étapes donc plus long, le caractère de « test thérapeutique
» qui, en cas d’échec, induira déception et perte de confiance. Les options de traitement
plus tardif sont plus sécurisantes pour l’orthodontiste comme pour le patient, mais elles
constitueraient pour certains une perte de chance et une condamnation a priori à plus
d’extractions et plus d’orientations chirurgicales. La présentation d’un cas de classe III
hyperdivergente où les hésitations à intervenir à divers stades de croissance, conduisent
finalement à un traitement chirurgical tardif, illustre bien pour nous ce problème du
choix de la date d’intervention.
Pour une prise en charge précoce des malocclusions de classe II
division 1
Authors: Chabre Claude
Published: March 2013

En présence d’une malocclusion de classe II division 1, faut-il traiter précocement en
denture mixte ou plus tardivement en denture adolescente? Dans une revue systématique
Cochrane, les auteurs concluent : « Les preuves suggèrent que mettre en place un
traitement orthodontique précoce pour les enfants ayant les dents antérieures du
maxillaire en proalvéolie n’est pas plus efficace qu’effectuer un traitement orthodontique
en une phase lorsque l’enfant est au début de l’adolescence. » Alors, faut-il attendre
pour traiter ? Certainement pas! De nombreux arguments en faveur des traitements précoces
existent : risque de fracture des incisives proéminentes, esthétique, bien-être de
l’enfant et épanouissement psychologique, diminution du temps de traitement multibague et
donc réduction des effets iatrogènes, création d’un environnement anatomique plus propice
au développement harmonieux des fonctions et de la croissance, sans oublier la notion
juridique de perte de chance. Ces différents éléments seront développés au cours d’une
revue de littérature et illustrés par un cas clinique.
Taux de succès et efficacité du traitement par activateur
Authors: Casutt Christoph , Pancherz Hans , Gawora Manfred , Ruf Sabine
Published: March 2013

Le taux de succès et l’efficacité du traitement par activateur ont été analysés dans une étude rétrospective multicentrique. Tous les patients de deux cliniques universitaires (Giessen, Allemagne et Berne, Suisse) remplissant les critères d’inclusion (malocclusion de classe II division 1, traitement par activateur, pas d’agénésie, pas d’extraction de dent permanente, pas de syndrome, pas de traitement orthodontique précédent à part une expansion maxillaire transversale, un dossier complet disponible) ont été sélectionnés pour l’étude qui a concerné au total 222 patients avec un âge moyen de 10,6 ans. Les dossiers des patients, les téléradiographies de profil et les moulages dentaires ont été évalués. Le traitement était considéré comme un succès si le rapport molaire était amélioré d’au moins une demi à trois quarts de cuspide selon que le leeway était utilisé ou non au cours du traitement. Les groupes ont été comparés à l’aide du test U de Wilcoxon-Mann-Whitney et du test de Kruskal-Wallis. Les variables discrètes ont été analysées par le khi carré et, quand la taille de l’échantillon était réduite, le test exact de Fischer. La régression logistique pas à pas a également été utilisée. Le taux de succès était de 64 % à Giessen et 66 % à Berne. Le seul facteur qui influençait significativement (P < 0,001) le succès du traitement était le niveau de coopération. Pour environ 27 % des patients dans les deux centres, l’occlusion après traitement était une classe I idéale. Pour 38 % supplémentaires, des améliorations marquées des rapports occlusaux ont été notées. Pour des sujets présentant des malocclusions de classe II division 1, traités à l’aide d’activateurs, une amélioration marquée des rapports inter-arcades de classe II peut être escomptée dans environ 65 % des cas. Le traitement par activateur est plus efficace en fin qu’en début de denture mixte.
Le préjudice réparable : la perte de chance
Authors: Béry Alain
Published: March 2013

La chance est la probabilité que quelque chose se produise et, en ce sens, la perte de chance peut se définir comme le préjudice résultant de la disparition de la probabilité d’un événement favorable (a contrario, la non-réalisation du risque). C’est un préjudice autonome, qu’il convient de distinguer du préjudice final. Le préjudice moral est une notion très proche de la perte de chance bien que reposant sur l’indemnisation d’un préjudice final d’affection.
Control and optimization of solute transport in a thin porous tube
Authors: Griffiths I. M. , Howell P. D. , Shipley R. J.
Published: March 2013

Predicting the distribution of solutes or particles in flows within porous-walled tubes is essential to inform the design of devices that rely on cross-flow filtration, such as those used in water purification, irrigation devices, field-flow fractionation, and hollow-fibre bioreactors for tissue-engineering applications. Motivated by these applications, a radially averaged model for fluid and solute transport in a tube with thin porous walls is derived by developing the classical ideas of Taylor dispersion. The model includes solute diffusion and advection via both radial and axial flow components, and the advection, diffusion, and uptake coefficients in the averaged equation are explicitly derived. The effect of wall permeability, slip, and pressure differentials upon the dispersive solute behaviour are investigated. The model is used to explore the control of solute transport across the membrane walls via the membrane permeability, and a parametric expression for the permeability required to generate a given solute distribution is derived. The theory is applied to the specific example of a hollow-fibre membrane bioreactor, where a uniform delivery of nutrient across the membrane walls to the extra-capillary space is required to promote spatially uniform cell growth.
Complex-scaled equation-of-motion coupled-cluster method with single and double substitutions for autoionizing excited states: Theory, implementation, and examples
Authors: Bravaya Ksenia B. , Zuev Dmitry , Epifanovsky Evgeny , Krylov Anna I.
Published: March 2013

Theory and implementation of complex-scaled variant of equation-of-motion coupled-cluster method for excitation energies with single and double substitutions (EOM-EE-CCSD) is presented. The complex-scaling formalism extends the EOM-EE-CCSD model to resonance states, i.e., excited states that are metastable with respect to electron ejection. The method is applied to Feshbach resonances in atomic systems (He, H−, and Be). The dependence of the results on one-electron basis set is quantified and analyzed. Energy decomposition and wave function analysis reveal that the origin of the dependence is in electron correlation, which is essential for the lifetime of Feshbach resonances. It is found that one-electron basis should be sufficiently flexible to describe radial and angular electron correlation in a balanced fashion and at different values of the scaling parameter, θ. Standard basis sets that are optimized for not-complex-scaled calculations (θ = 0) are not sufficiently flexible to describe the θ-dependence of the wave functions even when heavily augmented by additional sets.
Magnetodielectric response of coexisting phases in half doped manganites
Authors: Dash S. , Banerjee A. , Chaddah P.
Published: March 2013

The magnetic field dependence of dielectric permittivity and resistivity has been measured simultaneously in two separate half doped manganites Pr0.75Na0.25MnO3 and Pr0.5Ca0.5Mn0.975Al0.025O3. A gigantic change in dielectric permittivity was detected near the percolation threshold. The hysteresis in dielectric permittivity as well as in resistivity supports the first order nature of the insulator-metal transition while the tunability is due to the coexisting of phases across the transition. A highly resistivity correlated dielectric behaviour has been observed throughout the insulator to metal transition evidencing the dielectric catastrophe phenomenon. The field dependent dielectric data are analyzed in the framework of Maxwell-Garnett theory in association with Mott-Hubbard model.
Dust acoustic solitary waves in a magnetized electron depleted superthermal dusty plasma
Authors: Shahmansouri M. , Alinejad H.
Published: March 2013

A theoretical investigation has been made on the oblique propagation of arbitrary dust-acoustic solitary waves in an electron depleted magnetized dusty plasma which consists of kappa distributed ions and negatively charged warm dust fluid. The electron number density is assumed to be sufficiently depleted owing to the electron attachment during the dust charging process, i.e., ne≪ni. The propagation properties of two possible modes (in the linear regime) are investigated. It is found that deviation of ions from thermodynamic equilibrium leads to a decrease of the phase velocity of both modes. A nonlinear pseudopotential approach is employed to derive an energy-like equation which admits to investigate the occurrence of stationary solitary wave solution for the propagation of arbitrary amplitude. The effects of superthermality, obliqueness, and external magnetic field on the existence domain and nature of these solitary waves are discussed. Only negative polarity of solitary waves is found to exist. It is shown that an increase of ion superthermality leads to the appearance of the solitary waves with smaller Mach numbers. The influence of dust temperature on the existence domain of solitary structures is increase of the permitted Mach number. It is also found that the superthermality supports the solitary structures with larger amplitude.
Validation of a FAST semi-submersible floating wind turbine numerical model with DeepCwind test data
Authors: Coulling Alexander J. , Goupee Andrew J. , Robertson Amy N. , Jonkman Jason M. , Dagher Habib J.
Published: March 2013

There are global efforts in the offshore wind community to develop reliable floating wind turbine technologies that are capable of exploiting the abundant deepwater wind resource. These efforts require validated numerical simulation tools to predict the coupled aero-hydro-servo-elastic behavior of such systems. To date, little has been done in the public domain to validate floating wind turbine simulation tools. This work begins to address this problem by presenting the validation of a model constructed in the National Renewable Energy Laboratory (NREL) floating wind turbine simulator FAST with 1/50th-scale model test data for a semi-submersible floating wind turbine system. The test was conducted by the University of Maine DeepCwind program at Maritime Research Institute Netherlands' offshore wind/wave basin, located in the Netherlands. The floating wind turbine used in the tests was a 1/50th-scale model of the NREL 5-MW horizontal-axis reference wind turbine with a 126 m rotor diameter. This turbine was mounted to the DeepCwind semi-submersible floating platform. This paper first outlines the details of the floating system studied, including the wind turbine, tower, platform, and mooring components. Subsequently, the calibration procedures used for tuning the FAST floating wind turbine model are discussed. Following this calibration, comparisons of FAST predictions and test data are presented that focus on system global and structural response resulting from aerodynamic and hydrodynamic loads. The results indicate that FAST captures many of the pertinent physics in the coupled floating wind turbine dynamics problem. In addition, the results highlight potential areas of improvement for both FAST and experimentation procedures to ensure accurate numerical modeling of floating wind turbine systems.
Nanoporous tin oxide photoelectrode prepared by electrochemical anodization in aqueous ammonia to improve performance of dye sensitized solar cell
Authors: Teh Jun Jie , Guai Guan Hong , Wang Xuewan , Leong Kam Chew , Li Chang Ming , Chen Peng
Published: March 2013

In this work, a nanoporous thin film consisting of sieve-like tin oxide (SnO2) sheets was prepared by anodization of tin foil in aqueous ammonia and applied as a photoelectrode for dye-sensitized solar cell (DSSC). Compared to the conventional SnO2 nanoparticle-based photoelectrode, the anodized nanoporous SnO2 electrode offers higher short circuit current (6.85 vs. 3.64 mA/cm2) and open circuit voltage (0.56 vs. 0.51 V) due to better charge transportation and better suppression of charge recombination. Consequently, the power conversion efficiency of the DSSC equipped with the anodized SnO2 electrode is enhanced by 63%.
Electronic states in hydrogenated nanocrystalline silicon thin films detected by photocurrent technique
Authors: Zhang Rong , Chen Xinyi , Shen Wenzhong
Published: March 2013

Electronic states of hydrogenated nanocrystalline silicon (nc-Si:H) thin films had been investigated by temperature-dependent photocurrent measurements. It was found that the photocurrent in weak absorption region is dominated by a thermal-assisted transport due to the interfacial barrier. In strong absorption region, the direct transition is observed at the electronic state above the interfacial barrier, where the photocurrent abnormally increases with temperature decreasing due to the reduction of phonon scattering in the extended state transport. The temperature-dependent photocurrent is explained well by a simple coupled-rate equation model for both the weak and strong absorption regions, demonstrating the extended state in nc-Si:H.
The oxygen vacancy effect on the magnetic property of the LaMnO3−δ thin films
Authors: Zhao Ruiqiang , Jin Kuijuan , Xu Zhongtang , Guo Haizhong , Wang Le , Ge Chen , Lu Huibin , Yang Guozhen
Published: March 2013

The magnetic property of the LaMnO3−δ films was systematically investigated with the variation of the deposited oxygen pressure. The Curie temperature and the saturation magnetization of the films were found increased with the decrease of the oxygen pressure. We believe that the double exchange effect between Mn2+ and Mn3+ ions should be the origin of the ferromagnetism and the enhanced conductivity, where the Mn2+ ions are generated with the oxygen vacancies due to oxygen deficient, and the double-exchange interaction is enhanced with increasing the ratio of Mn2+/Mn3+. The results of the x-ray absorption spectroscopy support our conclusion as well.
Exclusion, extraction, and junction placement effects in the complementary barrier infrared detector
Authors: Ting David Z.-Y. , Soibel Alexander , Khoshakhlagh Arezou , Nguyen Jean , Höglund Linda , Keo Sam A. , Mumolo Jason M. , Gunapala Sarath D.
Published: March 2013

We demonstrate a long wavelength type-II superlattice (T2SL) complementary barrier infrared detector (CBIRD) with a double broken-gap junction bottom contact structure designed to reduce material growth demands without diminishing performance. Simulation suggests generation-recombination dark current suppression is the result of placing the electrical junction in the wide-gap hole barrier region, away from the metallurgical hole-barrier/absorber heterojunction. The lower turn-on bias of the modified CBIRD is explained in terms of junction properties. We suggest that minority carrier exclusion and extraction effects are partially responsible for the observed low diffusion-limited CBIRD dark current despite short T2SL minority carrier lifetimes.
Mechanistic studies of high temperature friction reduction in silver tantalate
Authors: Gao H. , Stone D. S. , Mohseni H. , Aouadi S. M. , Scharf T. W. , Martini A.
Published: March 2013

Silver tantalate (AgTaO3) has recently been identified as an excellent solid lubricant in sliding contacts at high temperatures. In this Letter, molecular dynamics simulations and experimental measurements are used to investigate the underlying mechanisms. Predicted and measured friction is observed to decrease with increasing temperature. Transmission electron microscopy reveals clusters of Ag surrounded by Ta2O5 in the surface layer. These features are reproduced and characterized quantitatively in the simulations. The findings indicate that low friction at high temperatures is enabled by the joint contributions of the hard Ta2O5 phase and lubricious Ag clusters in the shear- and temperature-induced surface layer.
InAs/In0.83Al0.17As quantum wells on GaAs substrate with type-I emission at 2.9 μm
Authors: Gu Y. , Zhang Y. G. , Chen X. Y. , Cao Y. Y. , Fang X. , Ding G. Q. , Zhou L.
Published: March 2013

This work reports on InAs quantum wells (QWs) grown on GaAs-based metamorphic In0.83Al0.17As buffers for type-I mid-infrared (MIR) emission. X-ray diffraction and Raman measurements show that the GaAs-based quantum wells have similar lattice and strain conditions with the InP-based structure. Atomic force microscope shows the smoother surface of the structure on GaAs substrate. For the GaAs-based quantum wells, favorable photoluminescence emission at 2.9 μm at 300 K has been achieved, and the optical quality is comparable to the structure on InP substrate. It is promising to employ this metamorphic quantum well structure for the demonstration of GaAs-based antimony-free mid-infrared lasers.
FANCJ couples replication past natural fork barriers with maintenance of chromatin structure
Authors: Schwab Rebekka A. , Nieminuszczy Jadwiga , Shin-ya Kazuo , Niedzwiedz Wojciech
Published: March 2013

Defective DNA repair causes Fanconi anemia (FA), a rare childhood cancer–predisposing syndrome. At least 15 genes are known to be mutated in FA; however, their role in DNA repair remains unclear. Here, we show that the FANCJ helicase promotes DNA replication in trans by counteracting fork stalling on replication barriers, such as G4 quadruplex structures. Accordingly, stabilization of G4 quadruplexes in ΔFANCJ cells restricts fork movements, uncouples leading- and lagging-strand synthesis and generates small single-stranded DNA gaps behind the fork. Unexpectedly, we also discovered that FANCJ suppresses heterochromatin spreading by coupling fork movement through replication barriers with maintenance of chromatin structure. We propose that FANCJ plays an essential role in counteracting chromatin compaction associated with unscheduled replication fork stalling and restart, and suppresses tumorigenesis, at least partially, in this replication-specific manner.
The scaffold protein EPG-7 links cargo–receptor complexes with the autophagic assembly machinery
Authors: Lin Long , Yang Peiguo , Huang Xinxin , Zhang Hui , Lu Qun , Zhang Hong
Published: March 2013

The mechanism by which protein aggregates are selectively degraded by autophagy is poorly understood. Previous studies show that a family of Atg8-interacting proteins function as receptors linking specific cargoes to the autophagic machinery. Here we demonstrate that during Caenorhabditis elegans embryogenesis, epg-7 functions as a scaffold protein mediating autophagic degradation of several protein aggregates, including aggregates of the p62 homologue SQST-1, but has little effect on other autophagy-regulated processes. EPG-7 self-oligomerizes and is degraded by autophagy independently of SQST-1. SQST-1 directly interacts with EPG-7 and colocalizes with EPG-7 aggregates in autophagy mutants. Mutations in epg-7 impair association of SQST-1 aggregates with LGG-1/Atg8 puncta. EPG-7 interacts with multiple ATG proteins and colocalizes with ATG-9 puncta in various autophagy mutants. Unlike core autophagy genes, epg-7 is dispensable for starvation-induced autophagic degradation of substrate aggregates. Our results indicate that under physiological conditions a scaffold protein endows cargo specificity and also elevates degradation efficiency by linking the cargo–receptor complex with the autophagic machinery.
Extreme C-terminal sites are posttranslocationally glycosylated by the STT3B isoform of the OST
Authors: Shrimal Shiteshu , Trueman Steven F. , Gilmore Reid
Published: March 2013

Metazoan organisms assemble two isoforms of the oligosaccharyltransferase (OST) that have different catalytic subunits (STT3A or STT3B) and partially nonoverlapping roles in asparagine-linked glycosylation. The STT3A isoform of the OST is primarily responsible for co-translational glycosylation of the nascent polypeptide as it enters the lumen of the endoplasmic reticulum. The C-terminal 65–75 residues of a glycoprotein will not contact the translocation channel–associated STT3A isoform of the OST complex before chain termination. Biosynthetic pulse labeling of five human glycoproteins showed that extreme C-terminal glycosylation sites were modified by an STT3B-dependent posttranslocational mechanism. The boundary for STT3B-dependent glycosylation of C-terminal sites was determined to fall between 50 and 55 residues from the C terminus of a protein. C-terminal NXT sites were glycosylated more rapidly and efficiently than C-terminal NXS sites. Bioinformatics analysis of glycopeptide databases from metazoan organisms revealed a lower density of C-terminal acceptor sites in glycoproteins because of reduced positive selection of NXT sites and negative selection of NXS sites.
Incentives for Innovation: Patents, Prizes, and Research Contracts
Authors: Clancy Matthew S. , Moschini GianCarlo
Published: March 2013

Innovation is essential for sustaining growth and economic development in a world that faces population increase, natural resource depletion, and environmental challenges. Incentives play a critical role in innovation because the required research and development activities are costly, and the resulting knowledge has the attributes of a public good. This paper discusses the economics of institutions and policies meant to provide incentives for research and innovation, and focuses on intellectual property rights, specifically patents, contracted research (for example grants), and innovation prizes. The main economic implications of these institutions are discussed, with particular attention paid to open questions and recent contributions.
Impact of Deficit Irrigation on Maize Physical and Chemical Properties and Ethanol Yield
Authors: Liu Liman , Klocke Norman , Yan Shuping , Rogers Danny , Schlegel Alan , Lamm Freddie , Chang Shing I. , Wang Donghai
Published: March 2013

The objective of this research was to study the effect of irrigation levels (five levels from 102 to 457 mm of water) on the physical and chemical properties and ethanol fermentation performance of maize. Twenty maize samples with two crop rotation systems, grain sorghum–maize and maize–maize, were harvested in 2011 and evaluated at the Kansas State University Southwest Research‐Extension Center near Garden City, Kansas, under a semiarid climate. Results showed that maize kernel weight, density, and breakage susceptibility decreased as irrigation level decreased. Starch contents of maize samples grown under a low irrigation level were approximately 3.0% lower than those under a high irrigation level. Protein contents ranged from 9.24 to 11.30% and increased as irrigation level decreased. Maize flour thermal and rheological properties were analyzed by differential scanning calorimetry and the Micro Visco‐Amylo‐Graph‐U device. Starch gelatinization temperature increased significantly as irrigation level decreased, whereas starch pasting viscosity decreased as irrigation level decreased. Free amino nitrogen (FAN) was significantly affected by irrigation level: it increased as irrigation decreased. Ethanol fermentation efficiency ranged from 90.96 to 92.48% and was positively correlated with FAN during the first 32 h of fermentation (r2 = 0.645). Deficit irrigation had a negative impact on ethanol yield. The maize with lower irrigation yielded about 4.0% less ethanol (44.14 mL/100 g of maize) than maize with high irrigation (45.92 mL/100 g of maize). Residual starch contents in the distillers dried grains with solubles were in a range of 0.80–1.02%. In conclusion, deficit irrigation had a significant effect on physical properties, chemical composition, ethanol yield, and fermentation efficiency of maize.
Two RxLR Avirulence Genes in Phytophthora sojae Determine Soybean Rps1k-Mediated Disease Resistance
Authors: Song Tianqiao , Kale Shiv D. , Arredondo Felipe D. , Shen Danyu , Su Liming , Liu Li , Wu Yuren , Wang Yuanchao , Dou Daolong , Tyler Brett M.
Published: March 2013

Resistance to Phytophthora sojae (Rps) genes have been widely used in soybean against root and stem rot diseases caused by this oomycete. Among 15 known soybean Rps genes, Rps1k has been the most widely used in the past four decades. Here, we show that the products of two distinct but closely linked RxLR effector genes are detected by Rps1k-containing plants, resulting in disease resistance. One of the genes is Avr1b-1, that confers avirulence in the presence of Rps1b. Three lines of evidence, including overexpression and gene silencing of Avr1b-1 in stable P. sojae transformants, as well as transient expression of this gene in soybean, indicated that Avr1b could trigger an Rps1k-mediated defense response. Some isolates of P. sojae that do not express Avr1b are nevertheless unable to infect Rps1k plants. In those isolates, we identified a second RxLR effector gene (designated Avr1k), located 5 kb away from Avr1b-1. Silencing or overexpression of Avr1k in P. sojae stable transformants resulted in the loss or gain, respectively, of the avirulence phenotype in the presence of Rps1k. Only isolates of P. sojae with mutant alleles of both Avr1b-1 and Avr1k could evade perception by the soybean plants carrying Rps1k.
First Report of Downy Mildew Caused by Peronospora belbahrii on Basil (Ocimum spp.) in Ontario
Authors: Saude C. , Westerveld S. , Filotas M. , McDonald M. R.
Published: March 2013

Basil (Ocimum spp.) is one of the most commercially significant fresh culinary herb crops worldwide. In Ontario, basil is grown both in the field and in the greenhouse. In the summer of 2011, basil plants grown in a research field at the Simcoe Research Station in Norfolk County, Ontario, Canada (44°15′N, 77°35′W), were infected with downy mildew. Infected leaves exhibited interveinal chlorotic lesions on the upper surface and clear to black sporulation on the abaxial leaf surfaces. Leaf senescence and defoliation occurred at high disease severity, which reduced marketable yield. Basil downy mildew symptoms were severe on leaves of cultivars Genovese and Sweet Basil, with 40 to 100% disease incidence. Based on morphological characteristics, the basil downy mildew causal agent was identified as Peronospora belbahrii Thines (4). Infected leaves were collected and microscopic observations of the sporulating lesions were carried out and the structures measured. Sporangiophores (n = 20) were hyaline with relatively long, straight trunks and were monopodially branched, with a length of 150 to 360 μm (average 285 μm). Sporangiophores ended with two slightly curved branchlets, the longer one measuring 15 to 27 μm (average 19 μm) and the shorter one 5 to 15 μm (average 9 μm). Sporangia (n = 50) were round, or slightly ovoid, olive to brown in color, and measured 29 × 25 μm (25 to 35 × 20 to 30 μm). Genomic DNA was extracted from 10 isolates and the nuclear ribosomal internal transcribed spacer (ITS) region was amplified with ITS4 and ITS5 primers and sequenced. The sequences of the 10 isolates were nearly identical. A BLAST search of the NCBI database with the ITS sequences (GenBank Accession No. KC756923) revealed a 98 to 100% similarity to the sequences of P. belbahrii (HQ730979, FJ436024, and HQ702191) isolated from sweet basil in Florida (3), California (1), and Hungary (2), respectively. To confirm pathogenicity, 5-week-old ‘Genovese’ seedlings were sprayed with a suspension of 1 × 105 sporangia/ml. Plants were kept in a growth chamber maintained at 23/18°C, 60 to 85% relative humidity, and 12/12 h light/dark. Non-inoculated plants served as controls. Basil downy mildew symptoms developed after 8 days on the inoculated plants and the pathogen was identified in association with symptoms consistent with downy mildew. The non-inoculated controls remained healthy. In North America, the occurrence of basil downy mildew has been reported since 2007 (3) and the disease has spread into several U.S. states. To our knowledge, this is the first report of downy mildew on sweet basil in Canada.

References: (1) C. L. Blomquist et al. Plant Dis. 93:968, 2009. (2) G. Nagy and A. Horvath. Plant Dis. 95:1034, 2011. (3) P. D. Roberts et al. Plant Dis. 98:199, 2009. (4) M. Thines et al. Mycol. Res. 113:532, 2009.
tale-Based Genetic Diversity of Chinese Isolates of the Citrus Canker Pathogen Xanthomonas citri subsp. citri
Authors: Ye Gang , Hong Ni , Zou Li-Fang , Zou Hua-Song , Zakria Muhammad , Wang Guo-Ping , Chen Gong-You
Published: March 2013

Pathotype A of Xanthomonas citri subsp. citri, the cause of citrus bacterial canker (CBC), is assumed to have originated in southern China. PthA, a type III secreted transcriptional activator-like effector (TALE), is a major pathogenicity determinant in X. citri subsp. citri. To investigate the diversity of X. citri subsp. citri in China, genomic and plasmid DNA of 105 X. citri subsp. citri isolates, collected from nine citrus-growing provinces of China, were digested by BamHI and hybridized with an internal repeat region of pthA. Strains were classified into 14 different genotypes (designated A to N) based on the number and size of pthA homologues. Genotypes B and G represented 19 and 62% of the isolate collection, respectively. Genotypes J and L lacked pthA or a pthA-hybridizing fragment and were less virulent on grapefruit (C. paradisi) and sweet orange (C. sinensis) compared with strains containing pthA or a pthA homologue. The virulence of genotypes J and L was increased when the wild-type pthA was introduced. Genotype I, which was isolated from sweet orange in Jiangxi province, caused typical canker symptoms and may contain a novel pthA-like gene. To our knowledge, this is the first description of genetic diversity in Chinese CBC strains based on tale gene analysis.
A Patient With Loin Hematuria Syndrome and Chronic Flank Pain Treated With Pulsed Radiofrequency of the Splanchnic Nerves
Authors: Moeschler Susan M. , Hoelzer Bryan C. , Eldrige Jason S.
Published: March 2013

Introduction:

Chronic abdominal and flank pain can be multifactorial and difficult to treat. Loin pain hematuria syndrome (LPHS) is a rare clinical cause of chronic abdominal and flank pain and is a diagnosis of exclusion with limited treatment options, ranging from medications to renal autotransplantation or even nephrectomy in resistant cases.

Case Description:

A 50-year-old man with a history of recurrent nephrolithiasis secondary to hypercalcemia presented to the pain clinic with bilateral flank pain. After failed conservative medical management, the decision was made to proceed to interventional modalities. He responded for a short duration to a splanchnic nerve block and subsequently had a longer analgesic response to pulsed radiofrequency (PRF) ablation to the splanchnic nerves.

Discussion:

LPHS is a difficult clinical scenario to diagnose and treat. Conservative options are often unsuccessful, but the more extreme interventions such as renal autotransplantation and nephrectomies are invasive and not always effective. In this case report, we describe the novel use of PRF to the splanchnic nerves as an alternative treatment modality for patients with LPHS.

Although the exact mechanism of action of PRF on nerve tissue is unclear, its indication in pain management requires further research and discussion. Our patient experienced substantial and sustained relief of his flank pain. PRF may be a viable option for patients with LPHS.
Influence of specific HSP70 domains on fibril formation of the yeast prion protein Ure2
Authors: Xu Li-Qiong , Wu Si , Buell Alexander K. , Cohen Samuel I. A. , Chen Li-Jun , Hu Wan-Hui , Cusack Sarah A. , Itzhaki Laura S. , Zhang Hong , Knowles Tuomas P. J. , Dobson Christopher M. , Welland Mark E. , Jones Gary W. , Perrett Sarah
Published: March 2013

Ure2p is the protein determinant of theSaccharomyces cerevisiaeprion state [URE3]. Constitutive overexpression of the HSP70 family memberSSA1cures cells of [URE3]. Here, we show that Ssa1p increases the lag time of Ure2p fibril formationin vitroin the presence or absence of nucleotide. The presence of the HSP40 co-chaperone Ydj1p has an additive effect on the inhibition of Ure2p fibril formation, whereas the Ydj1p H34Q mutant shows reduced inhibition alone and in combination with Ssa1p. In order to investigate the structural basis of these effects, we constructed and tested an Ssa1p mutant lacking the ATPase domain, as well as a series of C-terminal truncation mutants. The results indicate that Ssa1p can bind to Ure2p and delay fibril formation even in the absence of the ATPase domain, but interaction of Ure2p with the substrate-binding domain is strongly influenced by the C-terminal lid region. Dynamic light scattering, quartz crystal microbalance assays, pull-down assays and kinetic analysis indicate that Ssa1p interacts with both native Ure2p and fibril seeds, and reduces the rate of Ure2p fibril elongation in a concentration-dependent manner. These results provide new insights into the structural and mechanistic basis for inhibition of Ure2p fibril formation by Ssa1p and Ydj1p.
The specificity of the interaction betweenαB-crystallin and desmin filaments and its impact on filament aggregation and cell viability
Authors: Elliott Jayne L. , Der Perng Ming , Prescott Alan R. , Jansen Karin A. , Koenderink Gijsje H. , Quinlan Roy A.
Published: March 2013

CRYAB (αB-crystallin) is expressed in many tissues and yet the R120G mutation in CRYAB causes tissue-specific pathologies, namely cardiomyopathy and cataract. Here, we present evidence to demonstrate that there is a specific functional interaction of CRYAB with desmin intermediate filaments that predisposes myocytes to disease caused by the R120G mutation. We use a variety of biochemical and biophysical techniques to show that plant, animal and ascidian small heat-shock proteins (sHSPs) can interact with intermediate filaments. Nevertheless, the mutation R120G in CRYAB does specifically change that interaction when compared with equivalent substitutions in HSP27 (R140G) and into theCaenorhabditis elegansHSP16.2 (R95G). By transient transfection, we show that R120G CRYAB specifically promotes intermediate filament aggregation in MCF7 cells. The transient transfection of R120G CRYAB alone has no significant effect upon cell viability, although bundling of the endogenous intermediate filament network occurs and the mitochondria are concentrated into the perinuclear region. The combination of R120G CRYAB co-transfected with wild-type desmin, however, causes a significant reduction in cell viability. Therefore, we suggest that while there is an innate ability of sHSPs to interact with and to bind to intermediate filaments, it is the specific combination of desmin and CRYAB that compromises cell viability and this is potentially the key to the muscle pathology caused by the R120G CRYAB.