bluuebunny/crossref_metadata_2025 huggingface dataset:
Analytical study and evaluation results of power optimizers for distributed power conditioning in photovoltaic arrays
Authors: Orduz Ricardo , Solórzano Jorge , Egido Miguel Ángel , Román Eduardo
Published: November 2011

The use of modular or ‘micro’ maximum power point tracking (MPPT) converters at module level in series association, commercially known as “power optimizers”, allows the individual adaptation of each panel to the load, solving part of the problems related to partial shadows and different tilt and/or orientation angles of the photovoltaic (PV) modules. This is particularly relevant in building integrated PV systems. This paper presents useful behavioural analytical studies of cascade MPPT converters and evaluation test results of a prototype developed under a Spanish national research project. On the one hand, this work focuses on the development of new useful expressions which can be used to identify the behaviour of individual MPPT converters applied to each module and connected in series, in a typical grid‐connected PV system. On the other hand, a novel characterization method of MPPT converters is developed, and experimental results of the prototype are obtained: when individual partial shading is applied, and they are connected in a typical grid connected PV array. Copyright © 2011 John Wiley & Sons, Ltd.
Synthesis of fluorene‐based hyperbranched polymers for solution‐processable blue, green, red, and white light‐emitting devices
Authors: Shih Hung‐Min , Wu Ren‐Chi , Shih Ping‐I , Wang Chien‐Lung , Hsu Chain‐Shu
Published: November 2011

For the purpose of making hyperbranched polymer (Hb‐Ps)‐based red, green, blue, and white polymer light‐emitting diodes (PLEDs), three Hb‐Ps Hb‐terfluorene (Hb‐TF), Hb‐4,7‐bis(9,9′‐dioctylfluoren‐2‐yl)‐2,1,3‐benzothiodiazole (Hb‐BFBT), and Hb‐4,7‐bis[(9,9′‐dioctylfluoren‐2‐yl)‐thien‐2‐yl]‐2,1,3‐benzothiodiazole (Hb‐BFTBT) were synthesized via [2+2+2] polycyclotrimerization of the corresponding diacetylene‐functionalized monomers. All the synthesized polymers showed excellent thermal stability with degradation temperature higher than 355 °C and glass transition temperatures higher than 50 °C. Photoluminance (PL) and electroluminance (EL) spectra of the polymers indicate that Hb‐TF, Hb‐BFBT, and Hb‐BFTBT are blue‐green, green, and red emitting materials. Maximum brightness of the double‐layer devices of Hb‐TF, Hb‐BFBT, and Hb‐BFTBT with the device configuration of indium tin oxide/poly(3,4‐ethylene dioxythiophene):poly(styrene sulfonate)/light‐emitting polymer/CsF/Al are 48, 42, and 29 cd/m2; the maximum luminance efficiency of the devices are 0.01, 0.02, and 0.01 cd/A. By using host–guest doped system, saturated red electrophosphorescent devices with a maximum luminance efficiency of 1.61 cd/A were obtained when Hb‐TF was used as a host material doped with Os(fptz)2(PPh2Me2)2 as a guest material. A maximum luminance efficiency of 3.39 cd/A of a red polymer light‐emitting device was also reached when Hb‐BFTBT was used as the guest in the PFO (Poly(9,9‐dioctylfluorene)) host layer. In addition, a series of efficient white devices were, which show low turn‐on voltage (3.5 V) with highest luminance efficiency of 4.98 cd/A, maximum brightness of 1185 cd/m2, and the Commission Internationale de l'Eclairage (CIE) coordinates close to ideal white emission (0.33, 0.33), were prepared by using BFBT as auxiliary dopant. © 2011 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2012
The effect of ammonia flow in the AlN spacer on the electrical properties of InAlN/AlN/GaN HEMT structures
Authors: Gamarra Piero , Lacam Cedric , Magis Michelle , Tordjman Maurice , Poisson Marie‐Antoinette di Forte
Published: November 2011

During the past few years it has been reported that a thin AlN spacer of few nanometers needs to be inserted in InAlN/GaN high electron mobility transistors (HEMTs) to obtain high 2DEG carrier mobility. This work presents a systematic study of the effects of varying the ammonia flow in the AlN spacer of InAlN/AlN/GaN HEMTs grown by low pressure metalorganic vapour phase epitaxy (LP‐MOVPE). The strain state, the surface roughness and the growth rate of AlN were found to be dependent on the V/III ratio. In addition the ammonia flow in the interlayer has a strong impact on the structural properties of the subsequent InAlN barrier layer and on the electrical properties of the structure. A sheet resistance as low as 327 Ω/□ with a sheet carrier density of 1.5 × 1013 cm−2 has been obtained at room temperature.
Electric characteristics of ruthenium doped InP and its application for buried‐heterostructure lasers
Authors: Yamaguchi Harunaka , Nagira Takashi , Sakaino Go , Ono Kenichi , Takemi Masayoshi
Published: November 2011

In recent years, ruthenium (Ru) has been focused on the new semi‐insulated doping material for InP instead of Fe. Semi‐insulated InP is essential for the blocking layer of high modulation speed laser diode in terms of the capacitance and heat dissipation. In this paper, we have investigated the electric characteristic of Ru doped InP (Ru‐InP) which works both electron and hole trap characteristics. We fabricated n‐InP/Ru‐InP/n‐InP (n/Ru/n‐InP) and p‐InP/Ru‐InP/p‐InP (p/Ru/p‐InP) structure by Metal Organic Vapor Phase Epitaxy (MOVPE), and evaluated I‐V characteristics of its structure. It turned out from this experiment that the volume resistivity of p/Ru/p‐InP structure was higher than that of n/Ru/n‐InP. The resistivity of p/Ru/p‐InP was almost equal to that of n/Fe/n‐InP. We applied the Ru‐InP to the Buried‐Heterostructure DFB Laser as current blocking layer. We confirmed that the temperature dependence of LD characteristics was improved, and the output power was over 10mW even at 70 °C (© 2012 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
InGaN photodiodes using CaF2 insulator for high‐temperature UV detection
Authors: Sang L. W. , Liao M. Y. , Koide Y. , Sumiya M.
Published: November 2011

The authors report on a thermally‐stable ultraviolet‐A photodiode using CaF2 as the insulation layer in the metal‐insulator‐semiconductor (MIS) structure based on a high‐quality InGaN film. Compared to the Schottky photodiode (SPD) without the insulator, the MIS‐SPD device maintains a low reverse leakage current, a high photo‐to‐dark current ratio and fast response at the temperature as high as 523 K, indicating CaF2 as a good candidate for the III‐Nitride devices. The overall photoresponse properties of the MIS‐SPD are governed by the metal/insulator/semiconductor interfaces. The photocurrent gain at reverse biases from room‐temperature to 463 K is interpreted in term of thermionic‐field emission (TFE) and field emission mechanism, while TFE becomes the dominant mechanism at higher temperatures (© 2012 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Effect of GaN cap thickness on carrier dynamics in InGaN quantum wells
Authors: Kopylov O. , Shirazi R. , Svensk O. , Suihkonen S. , Sintonen S. , Sopanen M. , Kardynał B. E.
Published: November 2011

We have studied optical properties of single In0.1Ga0.9N quantum wells with GaN barriers in close proximity to the wafer surface (<10 nm). We have found that at room temperature a balance of radiative, non‐radiative recombination and complex surface states effects results in an optimum cap thickness of 3nm for achieving highest brightness emitters. At low temperature, we observe a behaviour that suggests that some surface states act as trapping centres for carriers rather than as a non‐radiative recombination channel. Temperature dependence of the photoluminescence decay curves shows that carrier lifetimes in all the wafers increase at lower temperatures and reach similar maximum value. Main features of the evolution of lifetimes with temperature can be explained satisfactory by a combination of radiative, non‐radiative recombination and above mentioned twofold surface effects. Detailed picture of the carrier dynamics is however complex and needs to include the modification of the electrostatic potential in the quantum wells positioned in the surface depletion regions (© 2012 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
X‐ray excited optical luminescence imaging of InGaN nano‐LEDs
Authors: Martínez‐Criado G. , Sans J. A. , Segura‐Ruiz J. , Tucoulou R. , Solé A. V. , Homs A. , Yoo J. , Yi J. G.‐C. , Alén B.
Published: November 2011

In this work, an imaging tool to investigate optical inhomogeneities with site and chemical sensitivities has been integrated in a synchrotron radiation nanoprobe. Coaxial GaN/In1–xGaxN/GaN/ZnO nanoarchitecture light emitting diode (LED) arrays are used to validate the scanning x‐ray excited luminescence technique. Elemental maps and luminescence images of the hexagonal InGaN multiple quantum wells and inner deposited layers are reported with 120 nm spatial resolution. Within the experimental accuracy, the X‐ray fluorescence results reveal an homogeneous distribution of the major elements involved in the pattern formation and heteroepitaxial nanotube growth. In comparison to the morphological pattern, the optical emissions from individual nanowires exhibit a striking spatial variation, indicating significant changes in the quantum confinement effects. (© 2012 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Ab initio electron energy‐loss spectra and depolarization effects: Application to carbon nanotubes
Authors: Amzallag E. , Ehinon D. , Martinez H. , Rérat M. , Baraille I.
Published: November 2011

We perform ab initio calculations of the optical absorption and electron energy‐loss spectra of (m, 0) single‐walled carbon nanotubes (with m ≠ 3n for m = 7‐25) in the framework of a “sum over states” (SOS) treatment of the Kohn‐Sham (KS) single‐particle orbitals and energies (CRYSTAL program). This approach tested on hexagonal boron nitride enables to fully assign the interband transitions in the imaginary part of the dielectric constant, in terms of atomic orbitals. As these calculations could not take into account the local field effects (depolarization effects), which take place for perpendicular polarizations in 2D and 1D periodic systems, we apply a simple method based on the Clausius‐Mossotti formula, relating the SOS and coupled‐perturbed KS polarizability values. This approach reproduces the main features of the spectra of boron nitride (001) surface and carbon nanotubes. © 2011 Wiley Periodicals, Inc. Int J Quantum Chem, 2012
Characterization of dyed textiles using TOF‐SIMS and FT‐IR
Authors: Lee Jihye , Ceglia A. , Kim Kang‐Jin , Lee Yeonhee
Published: November 2011

Within the field of archeology, textile research is of growing interest because of its potential to provide relevant information regarding either the development or the technological advancement of ancient populations or the socio‐economic and religious purposes of textile production. It is of paramount importance in cultural heritage research to use non‐destructive techniques. Therefore, dye analyses were performed using two non‐destructive methods: time‐of‐flight secondary ion mass spectrometry (TOF‐SIMS) and Fourier transform infrared spectroscopy (FT‐IR). In order to build a database, standard samples of dyed silk were prepared using several natural dye compounds; these samples were then analyzed with FT‐IR and TOF‐SIMS. Afterwards, spectroscopic analyses were carried out on five textile fragments coming from the 16th to the 18th century Korean tombs. FT‐IR and TOF‐SIMS spectra allowed the identification of fiber of the archeological textiles, making it possible to distinguish between the cotton and silk fibers. Furthermore, it was possible to identify indigo in three blue fabrics and to show its presence in a green textile. The results suggest that FT‐IR and TOF‐SIMS are two efficient and very helpful techniques for the characterization of excavated fabrics. Copyright © 2011 John Wiley & Sons, Ltd.
Ferroelectric Thin Films in Fluidic Environments: A New Interface for Sensing and Manipulation of Matter
Authors: Ferris Robert , Yellen Benjamin , Zauscher Stefan
Published: November 2011

For decades ferroelectric thin films (FETFs) have been the focus of research and development for next‐generation memory and semiconductor devices. FETFs are attractive because their polarization states are highly localized, stable, and switchable. These unique properties are also attractive for (bio)molecular sensing and separation applications. Polarization of both polymer and ceramic FETF results in the expression of a sustained high, non‐Faradaic, surface charge density. If these surface charges are maintained in aqueous environments, then the resulting electrostatic forces should induce the formation of electrolyte gradients and aid in the localization of charged species to the surface. Recently, there has been a growing interest in the interfacial properties of FETFs, specifically how they interact with liquid or gaseous phases. Recent work has shown that the FETF polarization state affects adsorption from the gaseous phase, surface catalysis, and cell growth. Encouraged by these findings, the use of FETFs in aqueous environments is explored. After an introduction to FETFs, the growing body of literature on the FETF interface is reviewed, along with the limited number of studies demonstrating FETF function in gas and liquid environments. Finally, the exciting possibilities that FETFs could bring to interfacial engineering and lab‐on‐chip (LOC) device design is reviewed.
Neurodevelopmental outcome of fetuses with increased nuchal translucency and apparently normal prenatal and/or postnatal assessment: a systematic review
Authors: Sotiriadis A. , Papatheodorou S. , Makrydimas G.
Published: November 2011

Objectives

To systematically review and, when feasible, pool, published data regarding the prevalence of childhood neurodevelopmental delay in fetuses with increased first‐trimester nuchal translucency (NT), normal karyotype and absence of structural defects or identifiable syndromes.

Methods

MEDLINE and SCOPUS searches using combinations of the terms ‘nuchal translucency’ AND ‘outcome*’ were complemented by perusal of the references of the retrieved articles and an additional automated search using the ‘search for related articles’ PubMed function. Only children with a normal karyotype and no structural defects or syndromic abnormalities were included in the analysis. Between‐studies heterogeneity was assessed using the I2 statistic.

Results

The total prevalence of developmental delay in all 17 studies was 28/2458 (1.14%; 95% CI, 0.79–1.64; I2 = 57.6%). Eight studies (n = 1567) used NT > 99th centile as the cut‐off; 15 children (0.96%; 95% CI, 0.58–1.58%) were reported as having developmental delay (I2 = 72.2%). Four studies (n = 669) used the 95th centile as the cut‐off for increased NT; seven children (1.05%; 95% CI, 0.51–4.88%) were reported as having developmental delay (I2 = 29.2%). Five studies used 3.0 mm as the cut‐off for increased NT; the pooled rate of developmental delay was six of 222 children (2.70%; 95% CI, 1.24–5.77%; I2 = 0.0%).

Conclusion

The rate of neurodevelopmental delay in children with increased fetal NT, a normal karyotype, normal anatomy and no identifiable genetic syndromes does not appear to be higher than that reported for the general population. More large‐scale, prospective case–control studies would be needed to enhance the robustness of the results. Copyright © 2011 ISUOG. Published by John Wiley & Sons, Ltd.
Biometry and fetal weight estimation by two‐dimensional and three‐dimensional ultrasonography: an intraobserver and interobserver reliability and agreement study
Authors: Lima J. C. , Miyague A. H. , Filho F. M. , Nastri C. O. , Martins W. P.
Published: November 2011

Objective

To evaluate and compare the intraobserver and interobserver reliability and agreement for the biparietal diameter (BPD), abdominal circumference (AC), femur length (FL) and estimated fetal weight (EFW) obtained by two‐dimensional ultrasound (2D‐US) and three‐dimensional ultrasound (3D‐US).

Methods

Singleton pregnant women between 24 and 40 weeks were invited to participate in this study. They were examined using 2D‐US in a blinded manner, twice by one observer, intercalated by a scan by a second observer, to determine BPD, AC and FL. In each of the three examinations, three 3D‐US datasets (head, abdomen and thigh) were acquired for measurements of the same parameters. We determined EFW using Hadlock's formula. Systematic errors between 3D‐US and 2D‐US were examined using the paired t‐test. Reliability and agreement were assessed by intraclass correlation coefficients (ICCs), limits of agreement (LoA), SD of differences and proportion of differences below arbitrary points.

Results

We evaluated 102 singleton pregnancies. No significant systematic error between 2D‐US and 3D‐US was observed. The ICC values were higher for 3D‐US in both intra‐ and interobserver evaluations; however, only for FL was there no overlap in the 95% CI. The LoA values were wider for 2D‐US, suggesting that random errors were smaller when using 3D‐US. Additionally, we observed that the SD values determined from 3D‐US differences were smaller than those obtained for 2D‐US. Higher proportions of differences were below the arbitrarily defined cut‐off points when using 3D‐US.

Conclusion

3D‐US improved the reliability and agreement of fetal measurements and EFW compared with 2D‐US. Copyright © 2012 ISUOG. Published by John Wiley & Sons, Ltd.
Predictive value of sequential models of uterine artery Doppler in pregnancies at high risk for pre‐eclampsia
Authors: Herraiz I. , Escribano D. , Gómez‐Arriaga P. I. , Herníndez‐García J. M. , Herraiz M. A. , Galindo A.
Published: November 2011

Objective

To evaluate the performance of models described previously for the prediction of pre‐eclampsia (PE), based on the sequential evaluation of uterine artery resistance at 11–13 weeks and 19–22 weeks, in a high‐risk population.

Methods

This was a prospective study in 135 women with singleton pregnancies and at least one of the following high‐risk conditions: PE and/or intrauterine growth restriction in a previous pregnancy, chronic hypertension, pregestational diabetes, renal disease, body mass index > 30 kg/m2, autoimmune disease (systemic lupus erythematosus, antiphospholipid syndrome or rheumatoid arthritis) and thrombophilia. Mean uterine artery pulsatility index (mUtA‐PI) at 11–13 and at 19–22 weeks' gestation was measured and analyzed according to quantitative and semi‐quantitative models, to predict late PE (resulting in delivery ≥ 34 weeks) and early PE (delivery < 34 weeks).

Results

Late PE developed in 21 (15.6%) pregnancies and early PE in six (4.4%). Using mUtA‐PI, the detection rates of late and early PE for a false‐positive rate of 10% were 14.3% and 33.3%, respectively, at 11–13 weeks, and 19.0% and 66.7%, respectively, at 19–22 weeks. Using a semi‐quantitative approach, the group of pregnant women with mUtA‐PI ≥ 90th percentile at both 11–13 and 19–22 weeks had a greater risk for early PE (odds ratio, 21.4 (95% CI, 2.5–184.7)) compared with the group with mUtA‐PI < 90th percentile at both periods. Using a quantitative approach, there was relative worsening in the mUtA‐PI (multiples of the median) from the first to the second trimester in all cases of early PE.

Conclusion

The application of semi‐quantitative and especially quantitative models to evaluate sequential changes in uterine artery Doppler findings between the first and second trimesters could be of additional value in assessing high‐risk women regarding their true risk of developing early PE. Copyright © 2012 ISUOG. Published by John Wiley & Sons, Ltd.
Sexing of mid‐incubation avian embryos as a management tool for zoological breeding programs
Authors: Jensen Thomas , Mace Michael , Durrant Barbara
Published: November 2011

Skewed sex ratios in zoo breeding programs may require housing single birds of an overrepresented gender, increasing demands on limited resources that could otherwise be diverted to breeding pairs or other important species. The ability to selectively incubate and hatch eggs of a desired sex represents a significant improvement in the long‐term management of avian species. This study describes a successful method for in ovo sexing of embryos from stage 30 through 42 of incubation (Hamburger and Hamilton [1951] J Morphol 88:49–92). A 0.01–1 µl blood sample was collected from either the vitelline vessel (VV) or the blood vessels of the chorio–allantoic membrane (CAM) of embryos at stages 14–18 or 30–42, respectively. DNA was isolated from whole blood using the Chelex method (Walsh et al. [1991] Biotechniques 10:506–513; Jensen et al., [2003] Zoo Biol 22:561–571). Sex was determined by PCR amplification using the previously described P2/P8 (Griffiths et al. [1998] Mol Ecol 7:1071–1075) and 1237L/1272H (Kahn et al. [1998] Auk 115:1074–1078) primers or by commercial vendor. Success rate was calculated as the percent of sampled embryos surviving to hatch. Embryos of the undesired sex were not incubated, thus not included in the calculation. There was a considerable difference in success rate when blood was collected from the stage 14–18 VV (0–25%, average 12%) vs. stage 30–42 CAM (33–100%, average 76%). In conclusion, in ovo sexing of embryos between stages 30 and 42 yields acceptable embryo survival rates while providing enough blood for genetic testing. Zoo Biol 31:694‐704, 2012. © 2011 Wiley Periodicals, Inc.
INDICO: the development of a resource for epigenomic study of Indians undergoing socioeconomic transition
Authors:   INdian DIabetes COnsortium
Published: November 2011

The INdian DIabetes COnsortium (INDICO) is an initiative to build a resource for genetic, epigenetic and clinical studies of type 2 diabetes (T2D) in socioeconomically transiting Indians. The consortium aims to follow selected communities which are undergoing rapid urbanization over a period of years to create a knowledge base for the better understanding of the gene-environment interaction in T2D. These resources can eventually be of value to not just the diabetes research community but would be able to contribute towards an improved understanding, diagnosis and prevention of numerous complex human disorders.
Determining what sets of trees can be the clique trees of a chordal graph
Authors: De Caria Pablo , Gutierrez Marisa
Published: November 2011

Chordal graphs have characteristic tree representations, the clique trees. The problems of finding one or enumerating them have already been solved in a satisfactory way. In this paper, the following related problem is studied: given a family "Equation missing" of trees, all having the same vertex set V, determine whether there exists a chordal graph whose set of clique trees equals "Equation missing". For that purpose, we undertake a study of the structural properties, some already known and some new, of the clique trees of a chordal graph and the characteristics of the sets that induce subtrees of every clique tree. Some necessary and sufficient conditions and examples of how they can be applied are found, eventually establishing that a positive or negative answer to the problem can be obtained in polynomial time. If affirmative, a graph whose set of clique trees equals "Equation missing" is also obtained. Finally, all the chordal graphs with set of clique trees equal to "Equation missing" are characterized.
Expressing the Erwinia amylovora type III effector DspA/E in the yeast Saccharomyces cerevisiae strongly alters cellular trafficking
Authors: Siamer Sabrina , Patrit Oriane , Fagard Mathilde , Belgareh-Touzé Naïma , Barny Marie-Anne
Published: November 2011

DspA/E belongs to the AvrE family of type III effector. Effectors of the AvrE family are injected via the T3SS in plant cell and are important to promote bacterial growth following infection and to suppress plant defense responses. Their mode of action in the plant cells is unknown. Here we study the physiological effects induced by dspA/E expression in the yeast Saccharomyces cerevisiae. Expression of dspA/E in the yeast inhibits cell growth. This growth inhibition is associated with perturbations of the actin cytoskeleton and endocytosis.
How to learn new tasks: Shop floor performance effects of knowledge transfer and performance feedback
Authors: Letmathe Peter , Schweitzer Marcus , Zielinski Marc
Published: November 2011

We investigate how learning and the task performance of individuals are affected by different forms of knowledge transfer. Whereas previous research has proven the positive performance impacts of knowledge transfer, self‐observation and feedback mechanisms individually, we explore the cumulative effect of these factors on learning and performance. With the help of two laboratory experimental studies reproducing manufacturing tasks that are typical for industrial production, we show that explicit knowledge transfer is superior to other forms of knowledge transfer. Externally provided performance feedback in the form of cost information and non‐financial performance indicators has no effect on the order of different forms of knowledge transfer. Moreover, external feedback does not even have an additional significant performance effect on learning new tasks irrespective of the type of knowledge transfer.
Continuity of the norm map on MilnorK-theory
Authors: Morrow Matthew
Published: November 2011

The norm map on the MilnorK-groups of a finite extension of complete, discrete valuation fields is continuous with respect to the unit group filtrations. The only proof in the literature, due to K. Kato, uses semi-global methods. Here we present an elementary algebraic proof.
Small-scale dynamo action in rotating compressible convection
Authors: Favier B. , Bushby P. J.
Published: November 2011

We study dynamo action in a convective layer of electrically conducting, compressible fluid, rotating about the vertical axis. At the upper and lower bounding surfaces, perfectly conducting boundary conditions are adopted for the magnetic field. Two different levels of thermal stratification are considered. If the magnetic diffusivity is sufficiently small, the convection acts as a small-scale dynamo. Using a definition for the magnetic Reynolds number ${R}_{M} $ that is based upon the horizontal integral scale and the horizontally averaged velocity at the mid-layer of the domain, we find that rotation tends to reduce the critical value of ${R}_{M} $ above which dynamo action is observed. Increasing the level of thermal stratification within the layer does not significantly alter the critical value of ${R}_{M} $ in the rotating calculations, but it does lead to a reduction in this critical value in the non-rotating cases. At the highest computationally accessible values of the magnetic Reynolds number, the saturation levels of the dynamo are similar in all cases, with the mean magnetic energy density somewhere between 4 and 9 % of the mean kinetic energy density. To gain further insights into the differences between rotating and non-rotating convection, we quantify the stretching properties of each flow by measuring Lyapunov exponents. Away from the boundaries, the rate of stretching due to the flow is much less dependent upon depth in the rotating cases than it is in the corresponding non-rotating calculations. It is also shown that the effects of rotation significantly reduce the magnetic energy dissipation in the lower part of the layer. We also investigate certain aspects of the saturation mechanism of the dynamo.
Home foreclosure and risk of psychiatric morbidity during the recent financial crisis
Authors: McLaughlin K. A. , Nandi A. , Keyes K. M. , Uddin M. , Aiello A. E. , Galea S. , Koenen K. C.
Published: November 2011

Background

A defining feature of the US economic downturn of 2008–2010 was the alarming rate of home foreclosure. Although a substantial number of US households have experienced foreclosure since 2008, the effects of foreclosure on mental health are unknown. We examined the effects of foreclosure on psychiatric symptomatology in a prospective, population-based community survey.

Method

Data were drawn from the Detroit Neighborhoods and Health Study (DNHS), waves 1 and 2 (2008–2010). A probability sample of predominantly African-American adults in Detroit, Michigan participated (n=1547). We examined the association between home foreclosure between waves 1 and 2 and increases in symptoms of DSM-IV major depression and generalized anxiety disorder (GAD).

Results

The most common reasons for foreclosure were an increase in monthly payments, an increase in non-medical expenses and a reduction in family income. Exposure to foreclosure between waves 1 and 2 predicted symptoms of major depression and GAD at wave 2, controlling for symptoms at wave 1. Even after adjusting for wave 1 symptoms, sociodemographics, lifetime history of psychiatric disorder at wave 1 and exposure to other financial stressors between waves 1 and 2, foreclosure was associated with an increased rate of symptoms of major depression [incidence density ratio (IDR) 2.4, 95% confidence interval (CI) 1.6–3.6] and GAD (IDR 1.9, 95% CI 1.4–2.6).

Conclusions

We provide the first prospective evidence linking foreclosure to the onset of mental health problems. These results, combined with the high rate of home foreclosure since 2008, suggest that the foreclosure crisis may have adverse effects on the mental health of the US population.
Co-morbid anxiety disorders in bipolar disorder and major depression: familial aggregation and clinical characteristics of co-morbid panic disorder, social phobia, specific phobia and obsessive-compulsive disorder
Authors: Goes F. S. , McCusker M. G. , Bienvenu O. J. , MacKinnon D. F. , Mondimore F. M. , Schweizer B. ,   National Institute of Mental Health Genetics Initiative Bipolar Disorder Consortium, DePaulo J. R. , Potash J. B.
Published: November 2011

Background

Co-morbidity of mood and anxiety disorders is common and often associated with greater illness severity. This study investigates clinical correlates and familiality of four anxiety disorders in a large sample of bipolar disorder (BP) and major depressive disorder (MDD) pedigrees.

Method

The sample comprised 566 BP families with 1416 affected subjects and 675 MDD families with 1726 affected subjects. Clinical characteristics and familiality of panic disorder, social phobia, specific phobia and obsessive-compulsive disorder (OCD) were examined in BP and MDD pedigrees with multivariate modeling using generalized estimating equations.

Results

Co-morbidity between mood and anxiety disorders was associated with several markers of clinical severity, including earlier age of onset, greater number of depressive episodes and higher prevalence of attempted suicide, when compared with mood disorder without co-morbid anxiety. Familial aggregation was found with co-morbid panic and OCD in both BP and MDD pedigrees. Specific phobia showed familial aggregation in both MDD and BP families, although the findings in BP were just short of statistical significance after adjusting for other anxiety co-morbidities. We found no evidence for familiality of social phobia.

Conclusions

Our findings suggest that co-morbidity of MDD and BP with specific anxiety disorders (OCD, panic disorder and specific phobia) is at least partly due to familial factors, which may be of relevance to both phenotypic and genetic studies of co-morbidity.
FREEDOM TO CHOOSE AND DEMOCRACY: THE EMPIRICAL QUESTION
Authors: Harding Robin
Published: November 2011

Intuitively it would seem that choice is important for democracy. Yet the empirical question, whether people actuallydovalue facing distinct platforms when they vote, remains open. In this paper I seek to remedy that situation by systematically addressing the question using cross-national survey data. Specifically, I investigate whether satisfaction with democracy depends on thenumberand/or thesubstanceof the choices that are available to people when they vote. The analysis offers strong support for the idea that what matters most to voters is thesubstanceof electoral choices. Although the number of choices also matters, the significance of this factor is conditional on being able to vote for a party that represents one's views, or on voting for the winner.
AN EXTENDED FRAMEWORK FOR PREFERENCE RELATIONS – CORRECTED VERSION
Authors: Gustafsson Johan E.
Published: November 2011

It is regretted that the originally published paper (doi:10.1017/S0266267111000010, published online 22 June 2011) was not the author's final amended version. We apologise for this oversight and reproduce the entire corrected paper here in print and online, with revised notation.

In order to account for non-traditional preference relations the present paper develops a new, richer framework for preference relations. This new framework provides characterizations of non-traditional preference relations, such as incommensurateness and instability, that may hold when neither preference nor indifference do. The new framework models relations with swaps, which are conceived of as transfers from one alternative state to another. The traditional framework analyses dyadic preference relations in terms of a hypothetical choice between the two compared alternatives. The swap framework extends this approach by analysing dyadic preference relations in terms of two hypothetical choices: the choice between keeping the first of the compared alternatives or swapping it for the second; and the choice between keeping the second alternative or swapping it for the first.
Protein hydrolysates and tissue repair
Authors: Thomson Rebecca L. , Buckley Jonathan D.
Published: November 2011

Protein hydrolysates provide a rich source of protein which is useful in situations where excess protein is needed, such as during repair of tissue damage. The consumption of protein hydrolysates has been shown to result in more rapid uptake of amino acids compared with whole proteins or free-form amino acid mixtures and some peptides in hydrolysates exhibit biological activity. Early studies showed that protein hydrolysates are more effectively utilised than intact proteins or amino acids. In addition, they promote a strong insulinotropic effect, which reduces protein breakdown and enhances muscle and tissue uptake of branched-chain amino acids. These effects contribute to benefits of protein hydrolysates for enhancing repair of tissue damage caused by surgery, ulcers, burns and muscle-damaging exercise. While there is evidence that protein hydrolysates may be useful for facilitating tissue repair, additional research is needed to further examine various roles of protein hydrolysates in this process.
Automated unsupervised authorship analysis using evidence accumulation clustering
Authors: LAYTON ROBERT , WATTERS PAUL , DAZELEY RICHARD
Published: November 2011

Authorship Analysis aims to extract information about the authorship of documents from features within those documents. Typically, this is performed as a classification task with the aim of identifying the author of a document, given a set of documents of known authorship. Alternatively, unsupervised methods have been developed primarily as visualisation tools to assist the manual discovery of clusters of authorship within a corpus by analysts. However, there is a need in many fields for more sophisticated unsupervised methods to automate the discovery, profiling and organisation of related information through clustering of documents by authorship. An automated and unsupervised methodology for clustering documents by authorship is proposed in this paper. The methodology is named NUANCE, forn-gram Unsupervised Automated Natural Cluster Ensemble. Testing indicates that the derived clusters have a strong correlation to the true authorship of unseen documents.
Role Transition from Mental Health Nurse to IAPT High Intensity Psychological Therapist
Authors: Robinson Simon , Kellett Stephen , King Ingrid , Keating Val
Published: November 2011

Background: The Improving Access to Psychological Therapies (IAPT) initiative has depended on the training of a new NHS mental health workforce. At step 3 of the stepped care model, capacity building has required the recruitment of a wide range of mental health professionals into high intensity therapists training posts. This shift naturally entails role transition on the part of trainees into delivering cognitive behavioural psychotherapy (CBP), but no previous research has examined the experience of such transitions. Aim: To describe the lived experience of transition from mental health nurse to IAPT high intensity therapist and to identify possible factors which moderate effective role conversions. Method: Six qualified high intensity therapists were interviewed using a semi-structured interview and the subsequent interviews transcribed. Thematic content analysis (TCA) was used to analyze personal accounts of role transition. All participants had previously been mental health nurses and attended the same IAPT high intensity therapist (HIT) training programme. Results: Six key themes were apparent from the TCA. Three interconnected themes concerning supervision (style, impact of approach and historical context) and three additional themes of the challenge of learning a new clinical approach, high need for support, and forming a new psychotherapist identity. Conclusions: Findings suggest supervision is the most important factor in supporting complex psychotherapy role transitions. Clinical supervisors may need to incorporate dedicated time on role and identity shift during CBP training to ensure effective assimilation and transition. Methodological short-comings are identified and discussed.
Report says Gulf of Mexico oil spill assessment should include ecosystem services approach
Authors: Showstack Randy
Published: November 2011

The oil spill in the Gulf of Mexico that resulted from the 20 April 2010 explosion of the Deepwater Horizon (DWH) platform drilling the Macondo well was so massive and affected such a large and deep region of the gulf that the process of determining environmental damage in the region should be more encompassing than a typical habitat and resource equivalency approach, according to a 9 November report by the U.S. National Research Council (NRC). The congressionally requested report calls for an ecosystem services approach to complement ongoing approaches to the damage evaluation for the spill that is being conducted through the ongoing Natural Resources Damage Assessment (NRDA) process triggered by the U.S. Oil Pollution Act (OPA) of 1990.
New geoscience teachers division for 2‐year colleges
Authors: Krumm Debra , Granshaw Frank
Published: November 2011

The role of 2‐year colleges (2YCs) in geoscience education is growing as the number of students enrolled in Earth and space science courses increases and as these institutions—which include community colleges and junior colleges—provide more students majoring in geoscience at public universities. In recognition of the increasing role of 2YCs in geoscience education, the National Association of Geoscience Teachers (NAGT) recently created a Geo2YC division for faculty, administrators, graduate students, and other geoscience professionals who share a professional interest in geoscience education at 2YCs. The mission of the new division, which is NAGT's first national division, is to serve as a forum for exchanging curricular ideas, concerns, and resources; establish a network of geoscience educators at 2YCs and other institutions with shared interests; sponsor NAGT 2YC activities and make recommendations to the NAGT Council in support of 2YC geoscience education; support and coordinate research on 2YC geoscience education; and advocate for 2YC geoscience education within NAGT and with other organizations.
Explaining unusual winter lightning in Japan
Authors: Shindo Takatoshi , Ishii Masaru , Williams Earle
Published: November 2011

Third International Symposium on Winter Lightning; Sapporo, Japan, 15–16 June 2011 Japan's meteorological setting in winter is unusual: It is an island in a relatively warm sea frequently overswept by colder air from Siberia. This sets up appreciable atmospheric instability in the fringe of the land adjacent to the Sea of Japan. Heavy snowstorms overlap the edge of the island and produce extraordinarily energetic lightning flashes that initiate from points on the ground (known as ground‐to‐cloud (GC) strokes) and wreak havoc on power lines and, more recently, wind turbines. These troublesome and costly conditions set the stage for the third in a series of conferences on winter lightning.
Fractures on curved surfaces: A classic problem solved
Authors: Balcerak Ernie
Published: November 2011

Sheeting joints—large fractures parallel to a curved rock surface—are common in many locations on Earth, such as the iconic Half Dome in Yosemite National Park in California. Explaining how these fractures form has been a classic unsolved problem in geology. Martel solved the problem by reformulating the static equilibrium equations in a curvilinear reference frame. His analysis shows that compression along a curved surface can induce tension perpendicular to the surface, which can cause subsurface cracks to open. He found that the curvature of a rock surface plays a key role in the formation of fractures.
Identification of a highly polymorphic tetranucleotide repeat locus (DXpS) at Xp and development of a DXpS/HUMARA biplex methylation-based PCR assay that enhances detection of X-chromosome inactivation
Authors: Machado Filipe , Ramos Ester , Radic Pamela , de Brasi Carlos , Medina-Acosta Enrique
Published: November 2011

The methylation-based PCR assay at the polymorphic (CAG)n repeat in exon 1 of the human androgen receptor _AR_ gene (HUMARA) is a standard method for determination of the methylation state of alleles in active X (Xa) and inactive X (Xi) chromosomes. HUMARA assay is endowed with heterozygosity rates ~85% worldwide. This means that in a proportion of females it is uninformative. The HUMARA genotype is not neutral, being linked to Kennedy´s disease. Moreover, allele designation and quantification from trinucleotide repeats demand normalizing for minor (stutter) products differing from the original template by multiples of the repeat unit. Here, we report on the identification of a highly polymorphic tetranucleotide repeat (named DXpS) mapping to within a CpG island on Xp. This island is 191 bp downstream from the start of the repeat element, and contains sites for the HhaI, HpaII and BstUI methyl-sensitive restriction enzymes. We developed the DXpS and the HUMARA markers into a biplex methylation-based quantitative fluorescent PCR assay. For DXpS we observed twelve alleles with negligible stuttering. DXpS exhibited a heterozygosity rate of 87% (n = 60), matching that of HUMARA. The combined informativeness of the biplex assay was 98%. Random and nonrandom X-inactivation patterns inferred with DXpS in phenotypically normal females and haemophiliac females carrying a defective F8 gene were highly concordant (r^2^ = 0.96) with HUMARA patterns. DXpS represents a notable advancement in detecting X-chromosome inactivation due to the observed high rate of heterozygosity, negligible stuttering, concordance with HUMARA, and the apparent neutrality of allelic variants. Financial support: FAPESP (09/10615-7), FAPERJ, CNPq.
PPARs and angiogenesis
Authors: Bishop-Bailey David
Published: November 2011

The PPAR (peroxisome-proliferator-activated receptor) family consists of three ligand-activated nuclear receptors: PPARα, PPARβ/δ and PPARγ. These PPARs have important roles in the regulation of glucose and fatty acid metabolism, cell differentiation and immune function, but were also found to be expressed in endothelial cells in the late 1990s. The early endothelial focus of PPARs was PPARγ, the molecular target for the insulin-sensitizing thiazolidinedione/glitazone class of drugs. Activation of PPARγ was shown to inhibit angiogenesis in vitro and in models of retinopathy and cancer, whereas more recent data point to a critical role in the development of the vasculature in the placenta. Similarly, PPARα, the molecular target for the fibrate class of drugs, also has anti-angiogenic properties in experimental models. In contrast, unlike PPARα or PPARγ, activation of PPARβ/δ induces angiogenesis, in vitro and in vivo, and has been suggested to be a critical component of the angiogenic switch in pancreatic cancer. Moreover, PPARβ/δ is an exercise mimetic and appears to contribute to the angiogenic remodelling of cardiac and skeletal muscle induced by exercise. This evidence and the emerging mechanisms by which PPARs act in endothelial cells are discussed in more detail.
To sprout or to split? VEGF, Notch and vascular morphogenesis
Authors: Gianni-Barrera Roberto , Trani Marianna , Reginato Silvia , Banfi Andrea
Published: November 2011

Therapeutic angiogenesis is an attractive strategy to treat patients suffering from peripheral or coronary artery disease. VEGF (vascular endothelial growth factor-A) is the fundamental factor controlling vascular growth in both development and postnatal life. The interplay between the VEGF and Notch signalling pathway has been recently found to regulate the morphogenic events leading to the growth of new vessels by sprouting. Angiogenesis can also take place by an alternative process, i.e. intussusception or vascular splitting. However, little is known about its role in therapeutic angiogenesis and its molecular regulation. In the present article, we briefly review how VEGF dose determines the induction of normal or aberrant angiogenesis and the molecular regulation of sprouting angiogenesis by Notch signalling, and compare this process with intussusception.
Synthesis, transport and incorporation into the nuclear envelope of A-type lamins and inner nuclear membrane proteins
Authors: González Jose M. , Andrés Vicente
Published: November 2011

The mammalian NE (nuclear envelope), which separates the nucleus from the cytoplasm, is a complex structure composed of nuclear pore complexes, the outer and inner nuclear membranes, the perinuclear space and the nuclear lamina (A- and B-type lamins). The NE is completely disassembled and reassembled at each cell division. In the present paper, we review recent advances in the understanding of the mechanisms implicated in the transport of inner nuclear membrane and nuclear lamina proteins from the endoplasmic reticulum to the nucleus in interphase cells and mitosis, with special attention to A-type lamins.
Class 3 semaphorins and their receptors in physiological and pathological angiogenesis
Authors: Staton Carolyn A.
Published: November 2011

Class 3 semaphorins (Sema3) are a family of secreted proteins that were originally identified as axon guidance factors mediating their signal transduction by forming complexes with neuropilins and plexins. However, the wide expression pattern of Sema3 suggested additional functions other than those associated with the nervous system, and indeed many studies have now indicated that Sema3 proteins and their receptors play a role in angiogenesis. The present review specifically focuses on recent evidence for this role in both physiological and pathological angiogenesis.