bluuebunny/crossref_metadata_2025 huggingface dataset:
The Gospel According to Dario Fo
Authors: Scuderi Antonio
Published: November 2012

For over half a century the Italian Nobel playwright and performer Dario Fo (b. 1926) developed a theatre that challenged the authority of hegemonic culture, while promoting the validity and dignity of folk and popular cultures. In his satire of the Catholic Church, Fo presents the paternalistic God the Father as an instrument of suppression, while showing Jesus as being closer to the hearts of the folk. His references to apocryphal gospels – the gospels of early Christianity that were rejected by the Roman Church – play into this schema. In two of his plays, First Miracle of the Christ Child (from Tale of a Tiger and Other Stories) and Johan Padan Discovers America, Fo borrows elements from various apocryphal texts as a basis to underscore his father/son dichotomy, and to contest hegemonic dominance. At the same time, he presents a human Jesus who is more akin to the Jesus of certain apocrypha than to official gospels. Antonio Scuderi is Professor of Italian at Truman State University in Missouri, where he founded the Italian programme. His interdisciplinary articles on Italian performance traditions have been published in leading journals of theatre, folklore and literary studies, and in essays for books. He is the author of Dario Fo and Popular Performance (Legas, 1998) and co-editor of Dario Fo: Stage, Text, and Tradition (Southern Illinois UP, 2000). His latest book, Dario Fo: Framing, Festival, and the Folkloric Imagination (Lexington Books, 2011), examines the influence of concepts derived from folk culture, anthropology, and Gramscian Marxism on the development of Fo's theatrical praxis.
Theatre as Intervention: Christoph Schlingensief's Hamlet in Zürich and Berlin, 2001
Authors: Irmer Thomas
Published: November 2012

Christoph Schlingensief (1960–2010) was a filmmaker, theatre director, and performance artist. In his Hamlet at the Schauspielhaus in Zürich in 2001 – his only staging of a classic – Schlingensief deployed the strategies of intervention typical of his whole work. In this article Thomas Irmer focuses on the actors' troupe in the play, performed by former neo-Nazis. Schlingensief was asking whether an audience would accept the reintegration of people who were determined to leave this extremist group with the support of the German government. At the same time, Schlingensief referred to a historical performance of Hamlet by Gustaf Gründgens, whose career in Nazi and post-war Germany is played in counterpoint against the neo-Nazi outsiders potentially to be reintegrated. Schlingensief's ambivalence here challenged ready-made opinions about overlap between political and aesthetic experience. Thomas Irmer is a scholar, theatre critic, and co-director of four documentary films on theatre, including Die Bühnenrepublik: Theatre in the GDR (2003) and Heiner Müller: a Biographical Portrait (2009). He teaches American theatre at the John F. Kennedy Institute for North American Studies at the Freie Universität in Berlin. He is a regular contributor to Theater Heute, editor of the book Castorf's Volksbühne (2003), and author of the forthcoming Life and Times of Andrzej T. Wirth.
Devine Intervention: Collaboration and Conspiracy in the History of the Royal Court
Authors: Storey Taryn
Published: November 2012

Taryn Storey believes that a series of letters recently discovered in the archive of the Arts Council of Great Britain (ACGB) makes it important that we reassess the genesis of the English Stage Company at the Royal Court. Dating from November 1952, the correspondence between George Devine and William Emrys Williams, the Secretary General of the ACGB, offers an insight into a professional and personal relationship that was to have a profound influence on the emerging Arts Council policy for drama. Storey makes the case that in 1953 Devine not only shaped his Royal Court proposal to fit the priorities of the ACGB Drama Panel, but that Devine and senior members of the ACGB then collaborated to ensure that the proposal became a key part of Arts Council strategic planning. Furthermore, she puts forward the argument that the relationship between Devine and Williams was instrumental to new writing and innovation becoming central to the future rationale for state subsidy to the theatre. Taryn Storey is a doctoral student at the University of Reading. Her PhD thesis examines the relationship between practice and policy in the development of new writing in post-war British theatre, and forms part of the AHRC-funded project ‘Giving Voice to the Nation: The Arts Council of Great Britain and the Development of Theatre and Performance in Britain 1945–1995’, a collaboration between the University of Reading and the Victoria and Albert Museum.
Mixed Fortunes in Oldenburg
Authors: Brown Mark
Published: November 2012

Report on the PAZZ Performing Arts Festival, held in Oldenburg, Germany, 20–29 April 2012.
NONCAUSAL VECTOR AUTOREGRESSION
Authors: Lanne Markku , Saikkonen Pentti
Published: November 2012

In this paper, we propose a new noncausal vector autoregressive (VAR) model for non-Gaussian time series. The assumption of non-Gaussianity is needed for reasons of identifiability. Assuming that the error distribution belongs to a fairly general class of elliptical distributions, we develop an asymptotic theory of maximum likelihood estimation and statistical inference. We argue that allowing for noncausality is of particular importance in economic applications that currently use only conventional causal VAR models. Indeed, if noncausality is incorrectly ignored, the use of a causal VAR model may yield suboptimal forecasts and misleading economic interpretations. Therefore, we propose a procedure for discriminating between causality and noncausality. The methods are illustrated with an application to interest rate data.
ASYMPTOTIC THEORY ON THE LEAST SQUARES ESTIMATION OF THRESHOLD MOVING-AVERAGE MODELS
Authors: Li Dong , Ling Shiqing , Li Wai Keung
Published: November 2012

This paper studies the asymptotic theory of least squares estimation in a threshold moving average model. Under some mild conditions, it is shown that the estimator of the threshold isn-consistent and its limiting distribution is related to a two-sided compound Poisson process, whereas the estimators of other coefficients are strongly consistent and asymptotically normal. This paper also provides a resampling method to tabulate the limiting distribution of the estimated threshold in practice, which is the first successful effort in this direction. This resampling method contributes to threshold literature. Simultaneously, simulation studies are carried out to assess the performance of least squares estimation in finite samples.
A FIXED-bPERSPECTIVE ON THE PHILLIPS–PERRON UNIT ROOT TESTS
Authors: Vogelsang Timothy J. , Wagner Martin
Published: November 2012

In this paper we extend fixed-basymptotic theory to the nonparametric Phillips–Perron (PP) unit root tests. We show that the fixed-blimits depend on nuisance parameters in a complicated way. These nonpivotal limits provide an alternative theoretical explanation for the well-known finite-sample problems of the PP tests. We also show that the fixed-blimits depend on whether deterministic trends are removed using one-step or two-step detrending approaches. This is in contrast to the asymptotic equivalence of the one- and two-step approaches under a consistency approximation for the long-run variance estimator. Based on these results we introduce modified PP tests that allow for asymptotically pivotal fixed-binference. The theoretical analysis is cast in the framework of near-integrated processes, which allows us to study the asymptotic behavior both under the unit root null hypothesis and for local alternatives. The performance of the original and modified PP tests is compared by means of local asymptotic power and a small finite-sample simulation study.
Postconcussive Complaints, Cognition, Symptom Attribution and Effort among Veterans
Authors: Larson Eric B. , Kondiles Bethany R. , Starr Christine R. , Zollman Felise S.
Published: November 2012

The etiology of postconcussive symptoms is not clearly understood. Development of etiological models of those symptoms will be helpful for accurate diagnosis and for planning effective treatment. Such a model should characterize the role of subject characteristics (education, premorbid intelligence), social psychological factors and symptom validity. Toward that end, the present study examined the association of postconcussive complaints and cognitive performance with symptom attribution and level of effort on testing. In a sample of 155 veterans, attribution to concussion was associated with endorsement of more severe postconcussive complaints, after controlling for the effects of other factors such as subject characteristics. Similarly, effort was associated with cognitive performance after controlling for the effects of these other factors. The present findings are consistent with previous reports that illness perception and effort on testing are associated with postconcussive complaints. This supports previous recommendations to routinely educate all concussion patients immediately after injury to reduce distorted perceptions and related persistent complaints. Finally, these findings highlight a need for routine assessment of patients’ perception of their injury to identify cases that may require psychotherapy to address any misattributions that develop. (JINS, 2013, 19, 1–8)
IMMIGRATION AND LARGE BANKNOTES
Authors: Fischer Andreas M.
Published: November 2012

Do immigrants have a higher demand for large-denominated banknotes than natives? This micro study examines whether banknote orders for CHF 1,000 notes are concentrated in Swiss municipalities with a high foreign-to-native ratio. The evidence for 251 Swiss municipalities finds that immigrants hoard fewer CHF 1,000 banknotes than natives. This empirical result means that immigration reduces seigniorage (per person) as measured by banknote orders. A 1% increase in the immigrant-to-native ratio is coincident with a reduction in banknote orders by CHF 4,000. This reduction is attributed to specific traits linked to immigrants.
Leidenfrost levitation: beyond droplets
Authors: Hashmi Ali , Xu Yuhao , Coder Benjamin , Osborne Paul A. , Spafford Jonathon , Michael Grant E. , Yu Gan , Xu Jie
Published: November 2012

Friction is a major inhibitor in almost every mechanical system. Enlightened by the Leidenfrost effect – a droplet can be levitated by its own vapor layer on a sufficiently hot surface – we demonstrate for the first time that a small cart can also be levitated by Leidenfrost vapor. The levitated cart can carry certain amount of load and move frictionlessly over the hot surface. The maximum load that the cart can carry is experimentally tested over a range of surface temperatures. We show that the levitated cart can be propelled not only by gravitational force over a slanted flat surface, but also self-propelled over a ratchet shaped horizontal surface. In the end, we experimentally tested water consumption rate for sustaining the levitated cart and compared the results to theoretical calculations. If perfected, this frictionless Leidenfrost cart could be used in numerous engineering applications where relative motion exists between surfaces.
Rfa2 is specifically dephosphorylated by Pph3 in Candida albicans
Authors: Wang Haitao , Gao Jiaxin , Wong Ada Hang-Heng , Hu Kangdi , Li Wanjie , Wang Yue , Sang Jianli
Published: November 2012

Rfa2 is a ssDNA (single-stranded DNA)-binding protein that plays an important role in DNA replication, recombination and repair. Rfa2 is regulated by phosphorylation, which alters its protein–protein interaction and protein–DNA interaction. In the present study, we found that the Pph3–Psy2 phosphatase complex is responsible for Rfa2 dephosphorylation both during normal G1-phase and under DNA replication stress in Candida albicans. Phosphorylated Rfa2 extracted from pph3Δ or psy2Δ G1 cells exhibited diminished binding affinity to dsDNA (double-stranded DNA) but not to ssDNA. We also discovered that Cdc28 (cell division cycle 28) and Mec1 are responsible for Rfa2 phosphorylation in G1-phase and under DNA replication stress respectively. Moreover, MS revealed that the domain of Rfa2 that was phosphorylated in G1-phase differed from that phosphorylated under the stress conditions. The results of the present study imply that differential phosphorylation plays a crucial role in RPA (replication protein A) regulation.
Can Semantic Enrichment Lead to Naming in a Word Extension Task?
Authors: Capone Singleton Nina
Published: November 2012

Purpose

This study examined the relationship between semantic enrichment and naming in children asked to extend taught words to untrained exemplars.

Method

Sixteen typically developing children (M= 32.63 months,SD= 4.02) participated in 3 word learning conditions that varied semantic enrichment via iconic (shape, function) or point gesture. At test, children named taught referents and 2 exemplars of each taught object: shape similar and shape dissimilar. Naming accuracy and errors were analyzed between conditions.

Results

The point condition never outperformed the shape or function conditions. In naming taught words, the shape condition was superior to the point condition, whereas the function condition was only marginally superior to the point condition. However, in naming untrained exemplars, only the shape condition was superior to the point condition, and there were fewer indeterminate errors in the shape condition.

Conclusion

Semantic enrichment supports naming, but shape cues appear to be particularly effective in using words beyond just-taught referents.
Procedural Visual Learning in Children With Specific Language Impairment
Authors: Gabriel Audrey , Stefaniak Nicolas , Maillart Christelle , Schmitz Xavier , Meulemans Thierry
Published: November 2012

Purpose

According to the
procedural deficit hypothesis
(PDH), difficulties in the procedural learning (PL) system may contribute to the language difficulties observed in children with specific language impairment (SLI).

Method

Fifteen children with SLI and their typically developing (TD) peers were compared on visual PL tasks—specifically, deterministic serial reaction time (SRT) tasks. In the first experiment, children with SLI and their TD peers performed the classical SRT task using a keyboard as response mode. In the second experiment, they performed the same SRT task but gave their responses through a touchscreen (instead of a keyboard) to reduce the motor and cognitive demands of the task.

Results

Although in
Experiment 1
, children with SLI demonstrated learning, they were slower and made more errors than did their TD peers. Nevertheless, these relative weaknesses disappeared when the nature of the response mode changed (
Experiment 2
).

Conclusions

In this study, the authors report that children with SLI may exhibit sequential learning. Moreover, the generally slower reaction times observed in previous deterministic SRT studies may be explained by the response mode used. Thus, our findings are not consistent with the predictions of the PDH, and these findings suggest that language impairments in SLI are not sustained by poor procedural learning abilities.
Monitoring Progress in Vocal Development in Young Cochlear Implant Recipients: Relationships Between Speech Samples and Scores From the Conditioned Assessment of Speech Production (CASP)
Authors: Ertmer David J. , Jung Jongmin
Published: November 2012

Purpose

To determine the concurrent validity of the Conditioned Assessment of Speech Production (CASP; Ertmer & Stoel-Gammon, 2008) and data obtained from speech samples recorded at the same intervals.

Method

Nineteen children who are deaf who received cochlear implants before their 3rd birthdays participated in the study. Speech samples and CASP scores were gathered at 6, 12, 18, and 24 months postactivation. Correlation analyses were conducted to assess the concurrent validity of CASP scores and data from samples.

Results

CASP scores showed strong concurrent validity with scores from speech samples gathered across all recording sessions (6–24 months).

Conclusions

The CASP was found to be a valid, reliable, and time-efficient tool for assessing progress in vocal development during young cochlear implant recipients' first 2 years of device experience.
A Response to Carnaby’s (2012) Letter to the Editor: “Comment on Revalidating Swallowing Assessments”
Authors: González-Fernández Marlís , Palmer Jeffrey B.
Published: November 2012

Purpose

The authors write this letter to clarify some of the points raised by Dr. Giselle Carnaby about their article titled “Clinical Experience Using the Mann Assessment of Swallowing Ability (MASA) for Identification of Patients at Risk for Aspiration in a Mixed-Disease Population” (González-Fernández, Sein, & Palmer, 2011). The intention of this letter is to ensure that the reader has a balanced perspective and the information necessary to interpret the results of the original publication.
Adapting wheat sowing dates to projected climate change in the Australian subtropics: analysis of crop water use and yield
Authors: Cammarano Davide , Basso Bruno , Stefanova Lydia , Grace Peter
Published: November 2012

Projected increases in atmospheric carbon dioxide concentration ([CO2]) and air temperature associated with future climate change are expected to affect crop development, crop yield, and, consequently, global food supplies. They are also likely to change agricultural production practices, especially those related to agricultural water management and sowing date. The magnitude of these changes and their implications to local production systems are mostly unknown. The objectives of this study were to: (i) simulate the effect of projected climate change on spring wheat (Triticum aestivum L. cv. Lang) yield and water use for the subtropical environment of the Darling Downs, Queensland, Australia; and (ii) investigate the impact of changing sowing date, as an adaptation strategy to future climate change scenarios, on wheat yield and water use. The multi-model climate projections from the IPCC Coupled Model Intercomparison Project (CMIP3) for the period 2030–2070 were used in this study. Climate scenarios included combinations of four changes in air temperature (0°C, 1°C, 2°C, and 3°C), three [CO2] levels (380 ppm, 500 ppm, and 600 ppm), and three changes in rainfall (–30%, 0%, and +20%), which were superimposed on observed station data. Crop management scenarios included a combination of six sowing dates (1 May, 10 May, 20 May, 1 June, 10 June, and 20 June) and three irrigation regimes (no irrigation (NI), deficit irrigation (DI), and full irrigation (FI)). Simulations were performed with the model DSSAT 4.5, using 50 years of daily weather data. We found that: (1) grain yield and water-use efficiency (yield/evapotranspiration) increased linearly with [CO2]; (2) increases in [CO2] had minimal impact on evapotranspiration; (3) yield increased with increasing temperature for the irrigated scenarios (DI and FI), but decreased for the NI scenario; (4) yield increased with earlier sowing dates; and (5) changes in rainfall had a small impact on yield for DI and FI, but a high impact for the NI scenario.
Cooperativeness and competitiveness as two distinct constructs: Validating the Cooperative and Competitive Personality Scale in a social dilemma context
Authors: Lu Su , Au Wing‐Tung , Jiang Feng , Xie Xiaofei , Yam Paton
Published: November 2012

The present research validated the construct and criterion validities of the Cooperative and Competitive Personality Scale (CCPS) in a social dilemma context. The results from three studies supported the notion that cooperativeness and competitiveness are two independent dimensions, challenging the traditional view that they are two ends of a single continuum. First, confirmatory factor analyses revealed that a two‐factor structure fit the data significantly better than a one‐factor structure. Moreover, cooperativeness and competitiveness were either not significantly correlated (Studies 1 and 3) or only moderately positively correlated (Study 2). Second, cooperativeness and competitiveness were differentially associated with Schwartz's Personal Values. These results further supported the idea that cooperativeness and competitiveness are two distinct constructs. Specifically, the individuals who were highly cooperative emphasized self‐transcendent values (i.e., universalism and benevolence) more, whereas the individuals who were highly competitive emphasized self‐enhancement values (i.e., power and achievement) more. Finally, the CCPS, which adheres to the trait perspective of personality, was found to be a useful supplement to more prevalent social motive measures (i.e., social value orientation) in predicting cooperative behaviors. Specifically, in Study 2, when social value orientation was controlled for, the CCPS significantly predicted cooperative behaviors in a public goods dilemma (individuals who score higher on cooperativeness scale contributed more to the public goods). In Study 3, when social value orientation was controlled for, the CCPS significantly predicted cooperative behaviors in commons dilemmas (individuals who score higher on cooperativeness scale requested fewer resources from the common resource pool). The practical implications of the CCPS in conflict resolution, as well as in recruitment and selection settings, are discussed.
The founders of the association for the study of nationalities: the case of Stepan Horak (1920–1986) and the Shevchenko Scientific Society, USA
Authors: Rudnytzky Leonid
Published: November 2012

The present article critically evaluates the contribution of the Shevchenko Scientific Society, USA, and the founder of the Association for the Study of Nationalities (ASN), Stepan Horak, to the genesis and development of the ASN.
A Comparative and Experimental Evaluation of Performance of Stocked Diploid and Triploid Brook Trout
Authors: Budy Phaedra , Thiede Gary P. , Dean Andrew , Olsen Devin , Rowley Gilbert
Published: November 2012

Despite numerous negative impacts, nonnative trout are still being stocked to provide economically and socially valuable sport fisheries in western mountain lakes. We evaluated relative performance and potential differences in feeding strategy and competitive ability of triploid versus diploid brook trout Salvelinus fontinalis in alpine lakes, as well as behavioral and performance differences of diploid and triploid brook trout in two controlled experimental settings: behavioral experiments in the laboratory and performance evaluations in ponds. Across lakes, catch per unit effort (CPUE) and relative weight (Wr) were not significantly different between ploidy levels. Mean sizes were also similar between ploidy levels except in two of the larger lakes where diploids attained slightly larger sizes (approximately 20 mm longer). We observed no significant differences between diploids and triploids in diet, diet preference, or trophic structure. Similarly, growth and condition did not differ between ploidy levels in smaller-scale pond experiments, and aggressive behavior did not differ between ploidy levels (fed or unfed fish trials) in the laboratory. Independent of ploidy level, the relative performance of brook trout varied widely among lakes, a pattern that appeared to be a function of lake size or a factor that covaries with lake size such as temperature regime or carrying capacity. In summary, we observed no significant differences in the relative performance of brook trout from either ploidy level across a number of indices, systems, and environmental conditions, nor any indication that one group is more aggressive or a superior competitor than the other. Collectively, these results suggest that triploid brook trout will offer a more risk-averse and promising management opportunity when they are stocked to these lakes and elsewhere to simultaneously meet the needs for the sport fishery and conservation objectives.

Received February 6, 2012; accepted August 27, 2012
Cdc42 promotes transendothelial migration of cancer cells through β1 integrin
Authors: Reymond Nicolas , Im Jae Hong , Garg Ritu , Vega Francisco M. , Borda d’Agua Barbara , Riou Philippe , Cox Susan , Valderrama Ferran , Muschel Ruth J. , Ridley Anne J.
Published: November 2012

Cancer cells interact with endothelial cells during the process of metastatic spreading. Here, we use a small interfering RNA screen targeting Rho GTPases in cancer cells to identify Cdc42 as a critical regulator of cancer cell–endothelial cell interactions and transendothelial migration. We find that Cdc42 regulates β1 integrin expression at the transcriptional level via the transcription factor serum response factor (SRF). β1 integrin is the main target for Cdc42-mediating interaction of cancer cells with endothelial cells and the underlying extracellular matrix, as exogenous β1 integrin expression was sufficient to rescue the Cdc42-silencing phenotype. We show that Cdc42 was required in vivo for cancer cell spreading and protrusion extension along blood vessels and retention in the lungs. Interestingly, transient Cdc42 depletion was sufficient to decrease experimental lung metastases, which suggests that its role in endothelial attachment is important for metastasis. By identifying β1 integrin as a transcriptional target of Cdc42, our results provide new insight into Cdc42 function.
Phytophthora capsici: A Soilborne Pathogen Dangerous on Grafted Tomato (Solanum lycopersicum × S. hirsutum) in Italy
Authors: Garibaldi A. , Gilardi G. , Baudino M. , Ortu G. , Gullino M. L.
Published: November 2012

During an extensive survey carried out in Piedmont (northern Italy) aimed at identifying the emerging soilborne diseases affecting tomato in commercial fields where alternatives to methyl bromide have been implemented in response to national and international regulations, sudden collapse of tomato plants, cv. Tomahawk, grafted on cv. Beaufort, were repeatedly observed in a commercial plastic tunnel operation. Affected plants suddenly collapsed 60 days after transplant during the month of May 2010. Symptoms included chlorosis, stunting, and severe root and crown rot, leading to sudden collapse of approximately 25% of the plants within 60 days of transplant. Symptomatic tissues from the root and collar of infected plants were surface disinfested for 1 min in a 1% NaOCl solution, rinsed for 5 min in water, and submerged in selective medium based on corn meal agar. A Phytophthora-like organism (2) with characteristic coenocytic hyphae was consistently isolated and transferred to V8 agar. The sporangia were spherical to ovoid, papillate, and 40 to 77 × 23 to 34 (average 55.1 × 30.3) μm. Oospores were globose and 22.2 to 30.8 μm. The internal transcribed spacer (ITS) region of rDNA of a single isolate was amplified using the primers ITS1/ITS4 and sequenced. BLAST analysis (1) of the 750-bp segment showed a 100% homology with the sequence of Phytophthora capsici JN382543.1. The nucleotide sequence has been assigned the GenBank Accession No. JX090306. Pathogenicity tests were performed on healthy 30-day-old tomato plants cv. Beaufort by using one strain of P. capsici grown for 15 days at 22 to 25°C on a mixture of 2:1 wheat/hemp kernels, and then 1 g per L of the inoculum was mixed into a substrate based on peat blonde/peat black (15:85 v/v). Two plants were transplanted into 3-L pots, with five replicates. Ten non-inoculated plants represented the control treatment; the trial was repeated once. All plants were kept in a greenhouse at temperatures ranging from 22 to 25°C. Inoculated plants became chlorotic 7 days after inoculation and root and crown rot developed 30 days after inoculation. Control plants remained symptomless. P. capsici consistently was reisolated from inoculated plants. In Italy, the presence of P. nicotianae on hybrids of Solanum lycopersicum × S. hirsutum is known (3), while, to the best of our knowledge, this is the first report of P. capsici on the hybrid S. lycopersicum × S. hirsutum in Italy. The economic importance of the disease can increase due to the expanding use of grafted tomato plants.

References: (1) S. F. Altschul et al. Nucleic Acids Res. 25:3389, 1997 (2) D. C. Erwin and O. K. Ribeiro. Phytophthora Diseases Worldwide. APS Press, St Paul, MN, 1996. (3) A. Garibaldi and M. L. Gullino. Acta Hortic. 833:35, 2010. (4) H. M. Masago et al. Phytopathology 67:425, 1977.
Structure of the dimeric RC–LH1–PufX complex from
Rhodobaca bogoriensis
investigated by electron microscopy
Authors: Semchonok Dmitry A. , Chauvin Jean-Paul , Frese Raoul N. , Jungas Colette , Boekema Egbert J.
Published: November 2012

Electron microscopy and single-particle averaging were performed on isolated reaction centre (RC)—antenna complexes (RC–LH1–PufX complexes) of
Rhodobaca bogoriensis
strain LBB1, with the aim of establishing the LH1 antenna conformation, and, in particular, the structural role of the PufX protein. Projection maps of dimeric complexes were obtained at 13 Å resolution and show the positions of the 2 × 14 LH1 α- and β-subunits. This new dimeric complex displays two open, C-shaped LH1 aggregates of 13 αβ polypeptides partially surrounding the RCs plus two LH1 units forming the dimer interface in the centre. Between the interface and the two half rings are two openings on each side. Next to the openings, there are four additional densities present per dimer, considered to be occupied by four copies of PufX. The position of the RC in our model was verified by comparison with RC–LH1–PufX complexes in membranes. Our model differs from previously proposed configurations for
Rhodobacter
species in which the LH1 ribbon is continuous in the shape of an S, and the stoichiometry is of one PufX per RC.
Regulation of the photosynthetic apparatus under fluctuating growth light
Authors: Tikkanen Mikko , Grieco Michele , Nurmi Markus , Rantala Marjaana , Suorsa Marjaana , Aro Eva-Mari
Published: November 2012

Safe and efficient conversion of solar energy to metabolic energy by plants is based on tightly inter-regulated transfer of excitation energy, electrons and protons in the photosynthetic machinery according to the availability of light energy, as well as the needs and restrictions of metabolism itself. Plants have mechanisms to enhance the capture of energy when light is limited for growth and development. Also, when energy is in excess, the photosynthetic machinery slows down the electron transfer reactions in order to prevent the production of reactive oxygen species and the consequent damage of the photosynthetic machinery. In this opinion paper, we present a partially hypothetical scheme describing how the photosynthetic machinery controls the flow of energy and electrons in order to enable the maintenance of photosynthetic activity in nature under continual fluctuations in white light intensity. We discuss the roles of light-harvesting II protein phosphorylation, thermal dissipation of excess energy and the control of electron transfer by cytochrome
b
6
f
, and the role of dynamically regulated turnover of photosystem II in the maintenance of the photosynthetic machinery. We present a new hypothesis suggesting that most of the regulation in the thylakoid membrane occurs in order to prevent oxidative damage of photosystem I.
Redox regulation of photosynthetic gene expression
Authors: Queval Guillaume , Foyer Christine H.
Published: November 2012

Redox chemistry and redox regulation are central to the operation of photosynthesis and respiration. However, the roles of different oxidants and antioxidants in the regulation of photosynthetic or respiratory gene expression remain poorly understood. Leaf transcriptome profiles of a range of
Arabidopsis thaliana
genotypes that are deficient in either hydrogen peroxide processing enzymes or in low molecular weight antioxidant were therefore compared to determine how different antioxidant systems that process hydrogen peroxide influence transcripts encoding proteins targeted to the chloroplasts or mitochondria. Less than 10 per cent overlap was observed in the transcriptome patterns of leaves that are deficient in either photorespiratory (
catalase
(
cat
)
2
) or chloroplastic (
thylakoid ascorbate peroxidase
(
tapx
)) hydrogen peroxide processing. Transcripts encoding photosystem II (PSII) repair cycle components were lower in glutathione-deficient leaves, as were the thylakoid NAD(P)H (nicotinamide adenine dinucleotide (phosphate)) dehydrogenases (NDH) mRNAs. Some thylakoid NDH mRNAs were also less abundant in tAPX-deficient and ascorbate-deficient leaves. Transcripts encoding the external and internal respiratory NDHs were increased by low glutathione and low ascorbate. Regulation of transcripts encoding specific components of the photosynthetic and respiratory electron transport chains by hydrogen peroxide, ascorbate and glutathione may serve to balance non-cyclic and cyclic electron flow pathways in relation to oxidant production and reductant availability.
Optimization of light harvesting and photoprotection: molecular mechanisms and physiological consequences
Authors: Horton Peter
Published: November 2012

The distinctive lateral organization of the protein complexes in the thylakoid membrane investigated by Jan Anderson and co-workers is dependent on the balance of various attractive and repulsive forces. Modulation of these forces allows critical physiological regulation of photosynthesis that provides efficient light-harvesting in limiting light but dissipation of excess potentially damaging radiation in saturating light. The light-harvesting complexes (LHCII) are central to this regulation, which is achieved by phosphorylation of stromal residues, protonation on the lumen surface and de-epoxidation of bound violaxanthin. The functional flexibility of LHCII derives from a remarkable pigment composition and configuration that not only allow efficient absorption of light and efficient energy transfer either to photosystem II or photosystem I core complexes, but through subtle configurational changes can also exhibit highly efficient dissipative reactions involving chlorophyll–xanthophyll and/or chlorophyll–chlorophyll interactions. These changes in function are determined at a macroscopic level by alterations in protein–protein interactions in the thylakoid membrane. The capacity and dynamics of this regulation are tuned to different physiological scenarios by the exact protein and pigment content of the light-harvesting system. Here, the molecular mechanisms involved will be reviewed, and the optimization of the light-harvesting system in different environmental conditions described.
Acclimation of leaves to low light produces large grana: the origin of the predominant attractive force at work
Authors: Jia Husen , Liggins John R. , Chow Wah Soon
Published: November 2012

Photosynthetic membrane sacs (thylakoids) of plants form granal stacks interconnected by non-stacked thylakoids, thereby being able to fine-tune (i) photosynthesis, (ii) photoprotection and (iii) acclimation to the environment. Growth in low light leads to the formation of large grana, which sometimes contain as many as 160 thylakoids. The net surface charge of thylakoid membranes is negative, even in low-light-grown plants; so an attractive force is required to overcome the electrostatic repulsion. The theoretical van der Waals attraction is, however, at least 20-fold too small to play the role. We determined the enthalpy change, in the spontaneous stacking of previously unstacked thylakoids in the dark on addition of Mg
2+
, to be zero or marginally positive (endothermic). The Gibbs free-energy change for the spontaneous process is necessarily negative, a requirement that can be met only by an increase in entropy for an endothermic process. We conclude that the dominant attractive force in thylakoid stacking is entropy-driven. Several mechanisms for increasing entropy upon stacking of thylakoid membranes in the dark, particularly in low-light plants, are discussed. In the light, which drives the chloroplast far away from equilibrium, granal stacking accelerates non-cyclic photophosphorylation, possibly enhancing the rate at which entropy is produced.
DetOx: a program for determining anomalous scattering factors of mixed-oxidation-state species
Authors: Sutton Karim J. , Barnett Sarah A. , Christensen Kirsten E. , Nowell Harriott , Thompson Amber L. , Allan David R. , Cooper Richard I.
Published: November 2012

Overlapping absorption edges will occur when an element is present in multiple oxidation states within a material.DetOxis a program for partitioning overlapping X-ray absorption spectra into contributions from individual atomic species and computing the dependence of the anomalous scattering factors on X-ray energy. It is demonstrated how these results can be used in combination with X-ray diffraction data to determine the oxidation state of ions at specific sites in a mixed-valance material, GaCl2.
Warifteine, a bisbenzylisoquinoline alkaloid, induces relaxation by activating potassium channels in vascular myocytes
Authors: Assis Ápio CL , Araújo Islania GA , Lima Renata PC , Almeida Mônica M , Marinho Alexsandro F , Barbosa‐Filho José M , Cruz Jader S , Silva Darizy F , Medeiros Isac A
Published: November 2012

The present study used functional and electrophysiological approaches to investigate the mechanisms by which warifteine, a bisbenzylisoquinoline alkaloid isolated from Cissampelos sympodialis Eichl., causes vasorelaxation of the rat thoracic aorta.

Warifteine (1 pmol/L–10 μmol/L) induced concentration‐dependent relaxation (pD2 = 9.40 ± 0.06; n = 5) of endothelium‐intact aortic rings precontracted with noradrenaline (10–100 μmol/L). The relaxation effects were not attenuated by removal of the endothelium. Warifteine also induced the relaxation of prostaglandin F2α (1–10 mmol/L)‐precontracted rings (pD2 = 9.2 ± 0.2; n = 8). In contrast, the relaxant activity of warifteine was nearly abolished in high K+ (80 mmol/L)‐precontracted aortic rings. In preparations incubated with 20 mmol/L KCl or with the K+ channel blockers tetraethylammonium (1, 3 and 5 mmol/L), iberiotoxin (20 nmol/L), 4‐aminopyridine (1 mmol/L) or glibenclamide (10 μmol/L), the vasorelaxant activity of warifteine was markedly reduced. However, BaCl2 (1 mmol/L) had no effect on the relaxant effects of warifteine.

In vascular myocytes, warifteine (100 nmol/L) significantly increased whole‐cell K+ currents (at 70 mV). Under nominally Ca2+‐free conditions, warifteine did not reduce extracellular Ca2+‐induced contractions in rings precontracted with high K+ or noradrenaline (100 μmol/L).

Together, the results of the present study indicate that warifteine induces potent concentration‐dependent relaxation in the rat aorta via an endothelium‐independent mechanism that involves the activation of K+ channels.
The determinants of minimal levator hiatus and their relationship to the puborectalis muscle and the levator plate
Authors: Shobeiri S Abbas , Rostaminia G , White D , Quiroz LH
Published: November 2012

Objective

To determine the muscles comprising the minimal levator hiatus.

Design

Cross‐sectional study.

Setting

The University of Oklahoma Health Sciences Center, USA.

Population

Eight female fresh frozen pelves and 80 nulliparouswomen.

Methods

Three‐dimensional endovaginal ultrasound was performed in eight fresh frozen female pelves. The structures of the levator hiatus were tagged with needles and the cadavers were dissected to identify the tagged structures. A group of 80 nullipara underwent 3D endovaginal ultrasound, and the minimal levator hiatus area, puborectalis area, and anorectal angle were assessed, and normal values were obtained.

Main outcome measures

Anatomic borders of minimal levator hiatus and normality in pelvic floor measurements.

Results

The pubococcygeus forms the inner lateral border and anterior attachment of the minimal levator hiatus to the pubic bone. The puboanalis fibres are immediately lateral to pubococcygeus attachments. There are variable contributions of the puborectalis fibres lateral to the puboanalis attachment. The posterior border of the minimal levator hiatus is formed by the levator plate. Eighty community‐dwelling nulliparous women underwent 3D endovaginal ultrasound. The median age was 47 years (range 22–70 years). The mean of minimal levator hiatus and puborectalis hiatus areas were 13.4 cm2 (±1.89 cm2 SD) and 14.8 cm2 (±2.16 cm2 SD). The mean anorectal and levator plate descent angles were 156° (±10.04° SD) and 15.9° (±8.28° SD).

Conclusion

Anterior and lateral borders of the minimal levator hiatus are formed mostly by pubococcygeus. The puborectalis, pubococcygeus, and iliococcygeus form the bulk of the levator plate.
Pregestational body mass index is related to neonatal abdominal circumference at birth—a Danish population‐based study
Authors: Tanvig M , Wehberg S , Vinter CA , Joergensen JS , Ovesen PG , Beck‐Nielsen H , Jensen DM , Christesen HT
Published: November 2012

Objectives

To examine the impact of maternal pregestational body mass index (BMI) and smoking on neonatal abdominal circumference (AC) and weight at birth. To define reference curves for birth AC and weight in offspring of healthy, nonsmoking, normal weight women.

Design

Population‐based study.

Setting

Data from the Danish Medical Birth Registry.

Population

All live singletons without congenital malformations in Denmark 2004–10.

Methods

Data on 366 886 singletons at 35+0 to 41+6 weeks+days of gestation were extracted and analysed using multivariate linear regressions.

Main outcome measures

Birth AC and weight in relation to pregestational maternal BMI, maternal smoking and medical conditions (any).

Results

Birth AC and weight increased with increasing pregestational BMI, and decreased with smoking (P < 0.0001). Reference curves were created for offspring of healthy, nonsmoking mothers with normal pregestational BMI. Mean AC ranged from 30.1 cm and 30.2 cm at 35 weeks of gestation to 33.9 cm and 34.1 cm at 41 weeks of gestation, for girls and boys, respectively. Mean birthweight ranged from 2581 and 2666 g at 35 weeks to 3705 and 3852 g at 41 weeks of gestation for girls and boys, respectively. Pregestational BMI correlated more to the Z score of birthweight than to the Z score of AC (P < 0.0001).

Conclusion

Birth AC and weight are affected by maternal smoking status and pregestational BMI. Pregestational BMI correlated more to birthweight than to AC. Using data from healthy, nonsmoking mothers with normal pregestational BMI we have provided new reference curves for birth AC and birthweight.
Opioid sensitivity in mice selectively bred to consume or not consume methamphetamine
Authors: Eastwood Emily C. , Phillips Tamara J.
Published: November 2012

There has been little investigation of genetic factors and associated mechanisms that influence risk for development of methamphetamine (MA) dependence. Selectively bred mouse lines that exhibit high (MAHDR) or low (MALDR) levels of MA intake in a two‐bottle choice MA drinking (MADR) procedure provide a genetic tool for this purpose. These lines were used to determine whether opioid sensitivity and MA intake are genetically associated, because opioid‐mediated pathways influence some effects of MA. Sensitivity to the analgesic effects of the μ‐opioid receptor (MOP‐r) agonist fentanyl (0.05, 0.1, 0.2, 0.4 mg/kg) was examined using two acute thermal tests (hot plate and tail flick) and one chronic pain test (magnesium sulfate abdominal constriction). Locomotor stimulant responses to fentanyl (0.05, 0.1, 0.2, 0.4 mg/kg) and morphine (10, 20, 30 mg/kg) were also examined. In addition, MADR was measured in the progenitor strains [(C57BL/6J (B6), DBA/2J (D2)] of the F2 population from which the selected lines were generated. The MADR lines did not differ in sensitivity to the analgesic effects of fentanyl; however, MALDR mice exhibited greater locomotor activation than MAHDR mice to both fentanyl and morphine. D2 mice consumed more MA than B6 mice. The line differences for MA consumption and morphine activation recapitulated B6 and D2 strain differences for these two traits, but not strain differences previously found for opioid analgesic responses. These results support a negative genetic correlation between MA consumption and sensitivity to the stimulant effects of opioids and suggest the involvement of MOP‐r regulated systems in MA intake.
Prefrontal correlates of approach preferences for alcohol stimuli in alcohol dependence
Authors: Ernst Lena H. , Plichta Michael M. , Dresler Thomas , Zesewitz Anna K. , Tupak Sara V. , Haeussinger Florian B. , Fischer Matthias , Polak Thomas , Fallgatter Andreas J. , Ehlis Ann‐Christine
Published: November 2012

An approach bias for alcohol stimuli (i.e. faster approach than avoidance reactions) might facilitate relapses in alcohol dependence. Neurobiological models suggest hypersensitivity in the reward system [inter alia nucleus accumbens and orbitofrontal cortex (OFC)] to cause pathologically enhanced approach impulses towards alcohol stimuli. At the same time, in alcohol dependence, these structures are only insufficiently controlled by a hypoactive dorsolateral prefrontal cortex (DLPFC). The present study investigated the cortical aspects of this model with functional near‐infrared spectroscopy in 21 alcohol‐dependent in‐patients and 21 healthy controls (HC; comparable in age, gender and education) during performance of the Approach‐Avoidance Task (AAT) for the first time. Complementing previous findings, in reaction times (RTs), patients showed stronger approach preferences for alcohol than non‐alcohol stimuli. For non‐alcohol stimuli, patients even displayed avoidance preferences. The reversed pattern was found in HC. Group differences in activity of the OFC were identical to those in RTs, revealing patients to assign higher subjective value to approaching alcohol stimuli. In both groups, regulatory activity in the right DLPFC was stronger during avoiding than approaching alcohol pictures. Probable awareness of the behavioural hypotheses due to explicit task instructions and patients' deficient prefrontal function might account for this equally aligned pattern. Results are discussed with regard to recent findings revealing a reduced behavioural approach bias and risk for relapse by applying a retraining version of the AAT. Functional measurements might serve as a method for monitoring the corresponding neurobiological changes and—possibly—predicting the success of such a training.
Salt chamber treatment is ineffective in treating eosinophilic inflammation in asthma
Authors: Sandell J. , Hedman J. , Saarinen K. , Haahtela T.
Published: November 2012

Background

We have shown that salt chamber treatment reduces airway hyper‐responsiveness as an add‐on therapy in adult asthmatics on inhaled corticosteroids.

Methods

We assessed whether this effect is due to the suppression of eosinophilic airway inflammation. Thirty‐nine adult asthmatics on inhaled corticosteroids were randomized to receive active salt chamber treatment with low‐salt treatment 6.6 mg/m3 (n = 14), high‐salt treatment 10.8 mg/m3 (n = 15) or placebo 0.3 mg/m3 (n = 10) 10 times in a 2 weeks' period in a double‐blind manner.

Results

The level of induced sputum eosinophilic cationic protein μg/l, was 3070 before and 4651 after the low‐salt treatment period, on average. In the high‐salt treatment group, it was 12 192 μg/l vs 11 803 and in the placebo group 3942 vs 4144, respectively. Salt chamber treatment had no effect on sputum eosinophil or neutrophil cell numbers.

Conclusions

The reduction in hyper‐responsiveness observed in the previous study is probably not due to the effect on eosinophilic inflammation.