bluuebunny/crossref_metadata_2025 huggingface dataset:
THE Z-TRANSFORM AND COMPARATIVE DYNAMICS IN DISCRETE-TIME MODELS
Authors: Gong Liutang , Wang Wei
Published: December 2011

This paper develops a general technique for the computation of comparative dynamics in perfect-foresight discrete-time models. The method developed here is both applicable and general; it can be used to analyze the effects of the perturbation of parameters on endogenous variables and the welfare of an economic system derived from more general multisector models. It is neither restricted to the system's dimensions nor restricted by the assumption of distinct eigenvalues in the system.
An exploratory factor analysis of nutritional biomarkers associated with major depression in pregnancy
Authors: Bodnar Lisa M , Wisner Katherine L , Luther James F , Powers Robert W , Evans Rhobert W , Gallaher Marcia J , Newby PK
Published: December 2011

Objective

Major depressive disorder (MDD) during pregnancy increases the risk of adverse maternal and infant outcomes. Maternal nutritional status may be a modifiable risk factor for antenatal depression. We evaluated the association between patterns in mid-pregnancy nutritional biomarkers and MDD.

Design

Prospective cohort study.

Setting

Pittsburgh, Pennsylvania, USA.

Subjects

Women who enrolled at ≤20 weeks’ gestation and had a diagnosis of MDD made with the Structured Clinical Interview for DSM-IV (Diagnostic and Statistical Manual of Mental Disorders, 4th edition) at 20-, 30- and 36-week study visits. A total of 135 women contributed 345 person-visits. Non-fasting blood drawn at enrolment was assayed for red cell essential fatty acids, plasma folate, homocysteine and ascorbic acid; serum 25-hydroxyvitamin D, retinol, vitamin E, carotenoids, ferritin and soluble transferrin receptors. Nutritional biomarkers were entered into principal components analysis.

Results

Three factors emerged: Factor 1, Essential Fatty Acids; Factor 2, Micronutrients; and Factor 3, Carotenoids. MDD was prevalent in 21·5 % of women. In longitudinal multivariable logistic models, there was no association between the Essential Fatty Acids or Micronutrients pattern and MDD either before or after adjustment for employment, education or pre-pregnancy BMI. In unadjusted analysis, women with factor scores for Carotenoids in the middle and upper tertiles were 60 % less likely than women in the bottom tertile to have MDD during pregnancy, but after adjustment for confounders the associations were no longer statistically significant.

Conclusions

While meaningful patterns were derived using nutritional biomarkers, significant associations with MDD were not observed in multivariable adjusted analyses. Larger, more diverse samples are needed to understand nutrition–depression relationships during pregnancy.
Role of microRNAs in immunity and organ transplantation
Authors: Spiegel Janine C. , Lorenzen Johan M. , Thum Thomas
Published: December 2011

Organ transplantation has evolved rapidly and there is now widespread use of donated organs for the treatment of end-stage organ failure. Although the therapeutic options achieving long-term graft survival have improved, acute and chronic rejections are still a major problem. Studies to identify noninvasive biomarkers for rejection and underlying molecular events have increased significantly in the past decade, but a major breakthrough is still missing. The recent discovery of small regulatory RNA molecules (microRNAs) resulted in a new and improved understanding of the mechanisms of gene regulation and also led to the development of the first new microRNA (miRNA)-based therapies. miRNAs are endogenous, single-stranded RNAs consisting of about 19–25 noncoding nucleotides, which have an important role in regulating gene expression. Additionally, circulating miRNAs that might be useful as novel disease biomarkers were detected. Here, we summarise current knowledge about the role of miRNAs in immunology and transplantation medicine and their role as potential biomarkers. We also focus on the molecular mechanisms and therapeutic implications of the use of miRNA-based therapeutic strategies to improve long-term allograft survival.
From Black and White to Colour; Educating and Engaging the Screen Addicts of 2011
Authors: Allbon Emily
Published: December 2011

This article, by Emily Allbon, is based on a presentation given at the BIALL Conference in 2011. She explores the depth of student engagement with online resources and how to handle the information-complacent law student. She discusses the development Learnmore, Lawbore's legal skills wiki, and concludes with thoughts over future development of this resource.
SharePoint and the Naked Law Librarian: How we can Harness our Core Skills to Promote Collaboration and Maximise the Return on Document Management Projects
Authors: Fishleigh Jackie
Published: December 2011

This article is based on the parallel session given by Jackie Fishleigh at the BIALL Conference in 2011 which looked at how Legal Information Professionals can get involved and contribute their skills to collaborative projects using SharePoint.
No-Cost and Low-Cost U.S. Legal Research
Authors: Shea Alison
Published: December 2011

When faced with a U.S. legal research question, what options does the non-U.S. based researcher have, short of purchasing a subscription to one of the fee-based databases or visiting a major research library? This article will briefly discuss a number of no-cost and low-cost resources in the context of the process required to perform U.S. legal research and will also provide explanations of the different types of primary sources that a legal researcher might encounter.
Voting Amid Violence: Electoral Democracy in Colombia. By Steven L. Taylor
Authors: Arias Desmond
Published: December 2011

Much of English-language writing on contemporary Colombia focuses on that country's extended armed conflict and the challenges posed by international drug trafficking to both hemispheric security and local political stability. Often overlooked, however, are the dynamics of Colombia's long-standing democratic political system. In his book, Steven L. Taylor offers readers a detailed discussion of the constitutional structure of party competition in one of Latin America's oldest democracies. Taylor is a capable scholar of Colombia's institutions and does an excellent job of shedding light on the complex interplay between parties in that country's evolving electoral system.
Feminist Policymaking in Chile. By Liesl Haas
Authors: Banaszak Lee Ann
Published: December 2011

The election of Michelle Bachelet as president of Chile in January 2006 was heralded in the world press as an advancement of women's rights in Chile. Not only did Bachelet's election increase women's representation at the highest levels, but it also raised expectations that Chile would adopt more women-friendly policies as well. Although focused on the years between the democratic transition and the election of Bachelet, Liesl Haas's Feminist Policymaking in Chile speaks volumes to the questions of how and why such representation makes a difference. Although the women's movement and feminist policymaking in Chile have been well mined by gender scholars, Haas provides a different perspective, both in terms of time frame and of theoretical argument. The book is notable for its extensive documentation of the legislative process, church activism, and feminist policymaking in Chile in the posttransition era. This rich description will make it valuable to gender scholars wishing to understand the Chilean case and to Latin Americanists wishing to understand more about gender politics in Chile. But my particular interest, and my focus in this review, concerns what the book tells us about the reasons that feminist policies get adopted in a particular place at a particular point in time.
Ethnicity and the Politics of AIDS
Authors: Posner Daniel N.
Published: December 2011

Evan Lieberman's Boundaries of Contagion: How Ethnic Politics Have Shaped Government Responses to Aids proceeds from a simple question of great importance to millions of people: “Why have some governments responded to AIDS more quickly and more broadly than others?” In answering this question, Lieberman employs a range of methods and engages a range of scholarly literatures dealing with health policy, comparative public policy, and ethnic politics. Because the book addresses “big” issues and bridges conventional divides in political science, we have invited a number of colleagues working broadly in comparative politics to comment on it.—Jeffrey C. Isaac, Editor
The Digital Origins of Dictatorships and Democracy: Information Technology and Political Islam. By Philip Howard. New York: Oxford University Press, 2010. 304p. $17.20.
Authors: Morozov Evgeny
Published: December 2011

Philip Howard's important book offers a timely and thorough treatment of a subject that has been catapulted into the global limelight thanks to recent revolutions in Tunisia and Egypt: the impact of the Internet on the political cultures in the Middle East.
SAGE: preliminary evaluation of an instrument for observing competence in CBT supervision
Authors: Milne Derek L. , Reiser Robert P. , Cliffe Tom , Raine Rosamund
Published: December 2011

Clinical supervision plays a recognized role in facilitating practitioner development and in promoting therapeutic fidelity, but instruments that can support such activities by measuring competence in supervision are rare and often psychometrically compromised. As part of a research programme intended to raise the empirical status of supervision, we describe the initial psychometric development of a new instrument for observing competence (Supervision: Adherence and Guidance Evaluation; SAGE). This instrument is suitable for measuring CBT supervision, and can be administered by self-rating or by an independent observer. Preliminary tests of the reliability and validity of SAGE suggest that it is a promising tool for evaluating supervision. In addition, SAGE can be applied readily and has good utility. In these respects, SAGE appears to have some advantages over existing instruments, and may therefore provide a basis for enhancing research and practice in CBT supervision. Suggestions for future research on SAGE are outlined, particularly the need for a generalizability analysis.
Kompetenzentwicklung von FrühpädagogInnen in Aus- und Weiterbildung
Authors: Nentwig-Gesemann Iris , Fröhlich-Gildhoff Klaus , Pietsch Stefanie
Published: December 2011

Zusammenfassung. Der Beitrag schließt an die geforderte Kompetenzorientierung von (hoch)schulischen Aus- und Weiterbildungen an. Im Mittelpunkt steht – nach einer Skizzierung des (frühpädagogischen) Kompetenzdiskurses – die Beschreibung eines Verfahrens der Erfassung von Kompetenzen, das der Praxis komplexer frühpädagogischer Handlungs- und Interaktionssituationen gerecht zu werden versucht. Mit dem Verfahren der „Dilemma-Situationen“ sollen dabei als herausfordernd und konflikthaft erlebte Situationen aus der eigenen Praxis geschildert, analysiert und bewertet oder aber vorgegebene standardisierte Situationen bearbeitet werden. Beide Formen können wiederum mithilfe eines Rasters standardisiert oder/und hermeneutisch-rekonstruktiv ausgewertet werden und als Basis für Feedbackgespräche, aber auch für empirische Studien zum Verlauf der Kompetenzentwicklung über mehrere Zeitpunkte hinweg genutzt werden. Damit kann sowohl die individuelle wie auch die Kompetenzentwicklung von Studiengruppen verfolgt und evaluiert werden.
Reconstructing past upwelling intensity and the seasonal dynamics of primary productivity along the Peruvian coastline from mollusk shell stable isotopes
Authors: Sadler James , Carré Matthieu , Azzoug Moufok , Schauer Andrew J. , Ledesma Jesus , Cardenas Fredy , Chase Brian M. , Bentaleb Ilhem , Muller Serge D. , Mandeng Magloire , Rohling Eelco J. , Sachs Julian P.
Published: December 2011

We present here a potential new method to evaluate past variations of the mean intensity of Peruvian coastal upwelling and of the seasonal timing of phytoplankton blooms. This method uses a combination of the monthly carbon and oxygen isotopic signals preserved in fossil mollusk shells, and a series of corrections to extract the variations of the dissolved inorganic carbon (DIC) δ13C. Based on the analysis of five shell samples (85 shells in total) from the southern Peruvian coast, we suggest that the mean coastal upwelling intensity can be determined from a linear relationship between average values of corrected shell δ13C and δ18O. This new potential proxy would bring additional independent information valuable to interpret paleoproductivity changes reconstructed from marine sediment of the nearby continental shelf. Results obtained on fossil samples from the middle Holocene show an increase in upwelling intensity during this period associated to a spatial reorganization of upwelling centers along the South Peruvian coast. At the seasonal scale, corrected shell δ13C enrichment indicates a phytoplankton bloom. Seasonal timing of phytoplankton blooms can be estimated by the lag with the annual temperature cycle reproduced by shell δ18O monthly variations. The results obtained with two modern shell samples indicate phytoplankton blooms occurring during summer and fall, consistently with in situ productivity observations. Our method relies on revisited assumptions about the influence of temperature and metabolism in mollusk shell δ13C. We further discussed the validity of these assumptions and the potential implications for the interpretation of similar data sets.
SMOS satellite L‐band radiometer: A new capability for ocean surface remote sensing in hurricanes
Authors: Reul Nicolas , Tenerelli Joseph , Chapron Bertrand , Vandemark Doug , Quilfen Yves , Kerr Yann
Published: December 2011

The Soil Moisture and Ocean Salinity (SMOS) mission currently provides multiangular L‐band (1.4 GHz) brightness temperature images of the Earth. Because upwelling radiation at 1.4 GHz is significantly less affected by rain and atmospheric effects than at higher microwave frequencies, these new SMOS measurements offer unique opportunities to complement existing ocean satellite high wind observations that are often contaminated by heavy rain and clouds. To illustrate this new capability, we present SMOS data over hurricane Igor, a tropical storm that developed to a Saffir‐Simpson category 4 hurricane from 11 to 19 September 2010. Thanks to its large spatial swath and frequent revisit time, SMOS observations intercepted the hurricane 9 times during this period. Without correcting for rain effects, L‐band wind‐induced ocean surface brightness temperatures (TB) were co‐located and compared to H*Wind analysis. We find the L‐band ocean emissivity dependence with wind speed appears less sensitive to roughness and foam changes than at the higher C‐band microwave frequencies. The first Stokes parameter on a ∼50 km spatial scale nevertheless increases quasi‐linearly with increasing surface wind speed at a rate of 0.3 K/m s−1 and 0.7 K/m s−1 below and above the hurricane‐force wind speed threshold (∼32 m s−1), respectively. Surface wind speeds estimated from SMOS brightness temperature images agree well with the observed and modeled surface wind speed features. In particular, the evolution of the maximum surface wind speed and the radii of 34, 50 and 64 knots surface wind speeds are consistent with GFDL hurricane model solutions and H*Wind analyses. The SMOS sensor is thus closer to a true all‐weather satellite ocean wind sensor with the capability to provide quantitative and complementary surface wind information of interest for operational Hurricane intensity forecasts.
Preliminary lightning observations over Greece
Authors: Chronis Themis G.
Published: December 2011

The first Precision Lightning Network, monitoring the Cloud‐to‐Ground (CG) lightning stroke activity over Greece and surrounding waters is operated and maintained by the Hellenic National Meteorological Service. This paper studies the regional (land/water interface), seasonal and diurnal variability of the CG strokes as a function of density, polarity and peak current. Additional investigation uniquely links the CG stroke current to sea surface salinity and cloud electrical capacitance. In brief, this study's major findings area as follows: (1) The seasonal maps of thunder days agree well with the regional climatic convective characteristics of the study area, (2) the CG diurnal variability is consistent with the global lightning activity observations over land and ocean, (3) the maxima of monthly averaged CG counts are located over land and water during typical summer and fall months respectively for both polarities, (4) CG peak currents show a distinct seasonality with larger currents during relatively colder months and smaller currents during summer months, and (5) strong linear trends between −CGs and sea surface salinity; (6) this trend is absent for +CGs data analysis of the employed database relate to the thunderstorm's RC constant and agrees with previous numerical modeling studies.
BMI, Waist Circumference, and Selected Cardiovascular Disease Risk Factors Among Preschool‐Age Children
Authors: Messiah Sarah E. , Arheart Kristopher L. , Natale Ruby A. , Hlaing WayWay M. , Lipshultz Steven E. , Miller Tracie L.
Published: December 2011

In adults, overweight is often associated with other cardiovascular disease (CVD) risk factors. We determined whether these associations were also present in young children. This study examined the relationships between elevated BMI (≥85th and ≥95th percentiles for age and sex) and the highest quintile of waist circumference (WC) with CVD risk factors, including fasting triglyceride (TGL), high‐ and low‐density lipoprotein (HDL and LDL), total cholesterol (TC), non‐HDL cholesterol, and C‐reactive protein (CRP) in 3,644 3‐ to 6‐year‐old children included in the 1999–2008 National Health and Nutrition Examination Surveys (NHANES). Results showed that 20% (highest quintile) of the sample had a TC >170 mg/dl, LDL >109 mg/dl, TGL >103 mg/dl, non‐HDL >128 mg/dl, CRP >0.13 mg/dl, WC >57.2 cm, and HDL <42 mg/dl. Increased BMI and WC were associated with increased CRP levels in non‐Hispanic black boys and girls, Hispanic boys, and non‐Hispanic white girls, whereas elevated TGL and non‐HDL cholesterol and low HDL cholesterol were generally associated with elevated BMI and WC in Hispanic children. TC and LDL cholesterol were not significantly associated with elevated weight in 3‐ to 6‐year‐olds. BMI and WC were similar in predicting the same risk factors. In summary, this analysis shows that in preschool‐age children, greater BMI and WC are associated with biomarkers that are related to CVD risk, but these associations vary by ethnicity. Child health providers should consider using both BMI and WC to identify young children who may be at risk for elevated CVD biomarkers.
Both p110α and p110β isoforms of PI3K can modulate the impact of loss-of-function of the PTEN tumour suppressor
Authors: Berenjeno Inma M. , Guillermet-Guibert Julie , Pearce Wayne , Gray Alexander , Fleming Stewart , Vanhaesebroeck Bart
Published: December 2011

The PI3K (phosphoinositide 3-kinase) pathway is commonly activated in cancer as a consequence of inactivation of the tumour suppressor PTEN (phosphatase and tensin homologue deleted on chromosome 10), a major negative regulator of PI3K signalling. In line with this important role of PTEN, mice that are heterozygous for a PTEN-null allele (PTEN+/− mice) spontaneously develop a variety of tumours in multiple organs. PTEN is a phosphatase with selectivity for PtdIns(3,4,5)P3, which is produced by the class I isoforms of PI3K (p110α, p110β, p110γ and p110δ). Previous studies indicated that PTEN-deficient cancer cell lines mainly depend on p110β, and that p110β, but not p110α, controls mouse prostate cancer development driven by PTEN loss. In the present study, we investigated whether the ubiquitously expressed p110α can also functionally interact with PTEN in cancer. Using genetic mouse models that mimic systemic administration of p110α- or p110β-selective inhibitors, we confirm that inactivation of p110β, but not p110α, inhibits prostate cancer development in PTEN+/− mice, but also find that p110α inactivation protects from glomerulonephritis, pheochromocytoma and thyroid cancer induced by PTEN loss. This indicates that p110α can modulate the impact of PTEN loss in disease and tumourigenesis. In primary and immortalized mouse fibroblast cell lines, both p110α and p110β controlled steady-state PtdIns(3,4,5)P3 levels and Akt signalling induced by heterozygous PTEN loss. In contrast, no correlation was found in primary mouse tissues between PtdIns(3,4,5)P3 levels, PI3K/PTEN genotype and cancer development. Taken together, our results from the present study show that inactivation of either p110α or p110β can counteract the impact of PTEN inactivation. The potential implications of these findings for PI3K-targeted therapy of cancer are discussed.
A cohesin–RAD21 interactome
Authors: Panigrahi Anil K. , Zhang Nenggang , Otta Subhendu K. , Pati Debananda
Published: December 2011

The cohesin complex holds the sister chromatids together from S-phase until the metaphase-to-anaphase transition, and ensures both their proper cohesion and timely separation. In addition to its canonical function in chromosomal segregation, cohesin has been suggested by several lines of investigation in recent years to play additional roles in apoptosis, DNA-damage response, transcriptional regulation and haematopoiesis. To better understand the basis of the disparate cellular functions of cohesin in these various processes, we have characterized a comprehensive protein interactome of cohesin–RAD21 by using three independent approaches: Y2H (yeast two-hybrid) screening, immunoprecipitation-coupled-MS of cytoplasmic and nuclear extracts from MOLT-4 T-lymphocytes in the presence and absence of etoposide-induced apoptosis, and affinity pull-down assays of chromatographically purified nuclear extracts from pro-apoptotic MOLT-4 cells. Our analyses revealed 112 novel protein interactors of cohesin–RAD21 that function in different cellular processes, including mitosis, regulation of apoptosis, chromosome dynamics, replication, transcription regulation, RNA processing, DNA-damage response, protein modification and degradation, and cytoskeleton and cell motility. Identification of cohesin interactors provides a framework for explaining the various non-canonical functions of the cohesin complex.
Thermally activated magnetization and resistance decay during near ambient temperature aging of Co nanoflakes in a confining semi-metallic environment
Authors: Kenning Gregory. G. , Heidt Christopher , Barnes Aaron , Martin James , Grove Benjamin , Madden Michael
Published: December 2011

We report the observation of magnetic and resistive aging in a self-assembled nanoparticle system produced in a multilayer Co/Sb sandwich. The aging decays are characterized by an initial slow decay followed by a more rapid decay in both the magnetization and resistance. The decays are large accounting for almost 70% of the magnetization and almost 40% of the resistance for samples deposited at 35 °C. For samples deposited at 50 °C the magnetization decay accounts for ∼50% of the magnetization and 50% of the resistance. During the more rapid part of the decay, the concavity of the slope of the decay changes sign and this inflection point can be used to provide a characteristic time. The characteristic time is strongly and systematically temperature dependent, ranging from ∼ 1 × 102 s at 400 K to ∼ 3 × 105 s at 320 K in samples deposited at 35 °C. Samples deposited at 50 °C displayed a 7-8-fold increase in the characteristic time (compared to the 35 °C samples) for a given aging temperature, indicating that this time scale may be tunable. Both the temperature scale and time scales are in potentially useful regimes. Pre-aging, scanning tunneling microscopy (STM) reveals that the Co forms in nanoscale flakes. During aging the nanoflakes melt and migrate into each other in an anisotropic fashion forming elongated Co nanowires. This aging behavior occurs within a confined environment of the enveloping Sb layers. The relationship between the characteristic time and aging temperature fits an Arrhenius law indicating activated dynamics.
Sedimentation of a charged colloidal sphere in a charged cavity
Authors: Keh Huan J. , Cheng Tsung F.
Published: December 2011

An analytical study is presented for the quasisteady sedimentation of a charged spherical particle located at the center of a charged spherical cavity. The overlap of the electric double layers is allowed, and the polarization (relaxation) effect in the double layers is considered. The electrokinetic equations that govern the ionic concentration distributions, electric potential profile, and fluid flow field in the electrolyte solution are linearized assuming that the system is only slightly distorted from equilibrium. Using a perturbation method, these linearized equations are solved for a symmetric electrolyte with the surface charge densities of the particle and cavity as the small perturbation parameters. An analytical expression for the settling velocity of the charged sphere is obtained from a balance among the gravitational, electrostatic, and hydrodynamic forces acting on it. Our results indicate that the presence of the particle charge reduces the magnitude of the sedimentation velocity of the particle in an uncharged cavity and the presence of the fixed charge at the cavity surface increases the magnitude of the sedimentation velocity of an uncharged particle in a charged cavity. For the case of a charged sphere settling in a charged cavity with equivalent surface charge densities, the net effect of the fixed charges will increase the sedimentation velocity of the particle. For the case of a charged sphere settling in a charged cavity with their surface charge densities in opposite signs, the net effect of the fixed charges in general reduces/increases the sedimentation velocity of the particle if the surface charge density of the particle has a greater/smaller magnitude than that of the cavity. The effect of the surface charge at the cavity wall on the sedimentation of a colloidal particle is found to increase with a decrease in the particle-to-cavity size ratio and can be significant in appropriate situations.
The dependence of singlet exciton relaxation on excitation density and temperature in polycrystalline tetracene thin films: Kinetic evidence for a dark intermediate state and implications for singlet fission
Authors: Burdett Jonathan J. , Gosztola David , Bardeen Christopher J.
Published: December 2011

The excited state dynamics of polycrystalline tetracene films are studied using femtosecond transient absorption in combination with picosecond fluorescence, continuing work reported in an earlier paper [J. J. Burdett, A. M. Muller, D. Gosztola, and C. J. Bardeen, J. Chem. Phys. 133, 144506 (2010)]. A study of the intensity dependence of the singlet state decay is conducted to understand the origins of the discrepancy between the broadband transient absorption and fluorescence experiments seen previously. High-sensitivity single channel transient absorption experiments allow us to compare the transient absorption dynamics to the fluorescence dynamics measured at identical laser fluences. At high excitation densities, an exciton-exciton annihilation rate constant of ∼1 × 10−8 cm3 s−1 leads to rapid singlet decays, but at excitation densities of 2 × 1017 cm−3 or less the kinetics of the transient absorption match those of the fluorescence. At these lower excitation densities, both measurements confirm that the initially excited singlet state relaxes with a decay time of 80 ± 3 ps, not 9.2 ps as claimed in the earlier paper. In order to investigate the origin of the singlet decay, the wavelength-resolved fluorescence dynamics were measured at 298 K, 77 K, and 4 K. A high-energy J-type emitting species undergo a rapid (∼100 ps) decay at all temperatures, while at 77 K and 4 K additional species with H-type and J-type emission lineshapes have much longer lifetimes. A global analysis of the wavelength-dependent decays shows that the initial ∼100 ps decay occurs to a dark state and not via energy transfer to lower energy bright states. Varying the excitation wavelength from 400 nm to 510 nm had no effect on the fast decay, suggesting that there is no energy threshold for the initial singlet relaxation. The presence of different emitting species at different temperatures means that earlier interpretations of the fluorescence behavior in terms of one singlet state that is short-lived due to singlet fission at high temperatures but long-lived at lower temperatures are probably too simplistic. The presence of a rapid singlet decay at all temperatures indicates that the initially created J-type singlet exciton decays to an intermediate that only produces free triplets (and delayed fluorescence) at high temperatures.
Highly clear conductive polymer electrode films hybridized with gold nanoparticles
Authors: Kim Jin-Yeol , Hwang Che-Ryong , Jo Sang-Hyun , Jung Woo-Gwang
Published: December 2011

Improved conductive poly(3,4-ethylenedioxy thiophene) (PEDOT) electrode films were made through hybridization with charged gold nanoparticles. The conductivity of these hybrid films increased more than seven times than the value for the PEDOT alone. The optimized films show a sheet resistance value down to 85 ohm·sq−1 at 85% transparency when PEDOT was hybridized with gold particles of 12 nm diameter, and the organic light-emitting diode devices deposited on these electrodes show a performance equivalent to that of devices based on a conventional indium tin oxide electrode.
Audio mixing in a tri-port nano-electro-mechanical device
Authors: Defoort M. , Lulla K. , Heron J.-S. , Bourgeois O. , Collin E. , Pistolesi F.
Published: December 2011

We report on experiments performed on a cantilever-based tri-port nano-electro-mechanical (NEMS) device. Two ports are used for actuation and detection through the magnetomotive scheme, while the third port is a capacitively coupled gate electrode. By applying a low frequency voltage signal on the gate, we demonstrate mixing in the mechanical response of the device, even for low magnetomotive drives without resorting to conduction measurements through the NEMS. The technique can thus be used, in particular, in the linear regime as an alternative to nonlinear mixing for normal conducting devices. An analytic theory is presented reproducing the data without free parameters.
Demonstration of forward inter-band tunneling in GaN by polarization engineering
Authors: Krishnamoorthy Sriram , Park Pil Sung , Rajan Siddharth
Published: December 2011

We report on the design, fabrication, and characterization of GaN interband tunnel junction showing forward tunneling characteristics. We have achieved very high forward tunneling currents (153 mA/cm2 at 10 mV, and 17.7 A/cm2 peak current) in polarization-engineered GaN/InGaN/GaN heterojunction diodes grown by plasma assisted molecular beam epitaxy. We also report the observation of repeatable negative differential resistance in interband III-Nitride tunnel junctions, with peak-valley current ratio of 4 at room temperature. The forward current density achieved in this work meets the typical current drive requirements of a multi-junction solar cell.
Electrical conductivity of platinum-implanted polymethylmethacrylate nanocomposite
Authors: Salvadori M. C. , Teixeira F. S. , Cattani M. , Brown I. G.
Published: December 2011

Platinum/polymethylmethacrylate (Pt/PMMA) nanocomposite material was formed by low energy ion implantation of Pt into PMMA, and the transition from insulating to conducting phase was explored. In situ resistivity measurements were performed as the implantation proceeded, and transmission electron microscopy was used for direct visualization of Pt nanoparticles. Numerical simulation was carried out using the TRIDYN computer code to calculate the expected depth profiles of the implanted platinum. The maximum dose for which the Pt/PMMA system remains an insulator/conductor composite was found to be ϕ0 = 1.6 × 1016 cm−2, the percolation dose was 0.5 × 1016 cm−2, and the critical exponent was t = 1.46, indicating that the conductivity is due only to percolation. The results are compared with previously reported results for a Au/PMMA composite.
Temperature-controlled epitaxy of InxGa1-xN alloys and their band gap bowing
Authors: Liu S. T. , Wang X. Q. , Chen G. , Zhang Y. W. , Feng L. , Huang C. C. , Xu F. J. , Tang N. , Sang L. W. , Sumiya M. , Shen B.
Published: December 2011

InxGa1-xN alloys (0 ≤ x ≤ 1) have been grown on GaN/sapphire templates by molecular beam epitaxy. Growth temperature controlled epitaxy was proposed to modulate the In composition so that each InxGa1-xN layer was grown at a temperature as high as possible and thus their crystalline quality was improved. The bandgap energies of the InxGa1-xN alloys have been precisely evaluated by optical transmission spectroscopy, where the effect of residual strain and electron concentration (the Burstein-Moss effect) on the bandgap energy shift has been considered. Finally, a bowing parameter of ∼1.9 ± 0.1 eV has been obtained by the well fitting In-composition dependent bandgap energy.
Synthesis of Stabilized Phosphinidenoid Complexes Using Weakly Coordinating Cations
Authors: Duan Lili , Nesterov Vitaly , Runyon Jason W. , Schnakenburg Gregor , Arduengo III Anthony J. , Streubel Rainer
Published: December 2011

The formation of phosphinidenoid complex salts having weakly coordinating cations (WCCs) is reported via treatment of P-functional phosphane complexes with N,N’-di-tert-butyl imidazol-2-ylidene or a P4-t-Bu phosphazene base. The thermal stability of phosphinidenoid complex salts is dependent upon the P–X substituents and the nature of the WCC. The complexes were characterized by multinuclear NMR spectroscopy and confirmed by single-crystal X-ray structure.
The health of newly arrived refugees to the Top End of Australia: results of a clinical audit at the Darwin Refugee Health Service
Authors: Johnston Vanessa , Smith Le , Roydhouse Heather
Published: December 2011

Accurate data on the health of refugees in primary care is vital to inform clinical practice, monitor disease prevalence, influence policy and promote coordination. We undertook a retrospective clinical audit of newly arrived refugees attending the Darwin refugee primary health service in its first 12 months of operation. Data were collected from the clinic files of refugee patients who attended for their initial health assessment from 1 July 2009 to 30 June 2010 and were analysed descriptively. Among 187 refugees who attended in 2009–2010, ~60% were from Asia and 42% were female. The most common diagnoses confirmed by testing were vitamin D deficiency (23%), hepatitis B carrier status (22%), tuberculosis infection (18%), schistosomiasis (17%) and anaemia (17%). The most common documented health conditions recorded by the GPs were vitamin D deficiency or insufficiency (66%), followed by schistosomiasis (24%) and dental disease (23%). This clinical audit adds to a limited evidence base suggesting a high prevalence of infectious disease, nutrient deficiency and dental disease among refugees arriving to Australia. GPs involved in the care of refugees must be aware of the epidemiology of disease in this group, as some diseases are rare among the general Australian population. Our results also highlight the ongoing need for advocacy to address service constraints such as limited public dental access for this population.
CO AND H2 ABSORPTION IN THE AA TAURI CIRCUMSTELLAR DISK*
Authors: France Kevin , Burgh Eric B. , Herczeg Gregory J. , Schindhelm Rebecca N. , Yang Hao , Abgrall Hervé , Roueff Evelyne , Brown Alexander , Brown Joanna M. , Linsky Jeffrey L.
Published: December 2011

The direct study of molecular gas in inner protoplanetary disks is complicated by uncertainties in the spatial distribution of the gas, the time variability of the source, and the comparison of observations across a wide range of wavelengths. Some of these challenges can be mitigated with far-ultraviolet spectroscopy. Using new observations obtained with the Hubble Space Telescope Cosmic Origins Spectrograph, we measure column densities and rovibrational temperatures for CO and H2 observed on the line of sight through the AA Tauri circumstellar disk. CO A – X absorption bands are observed against the far-UV continuum. The CO absorption is characterized by log10(N(12CO)) = 17.5 ± 0.5 cm−2 and T
rot(CO) = 500+500
−200 K, although this rotational temperature may underestimate the local kinetic temperature of the CO-bearing gas. We also detect 13CO in absorption with an isotopic ratio of ∼20. We do not observe H2 absorption against the continuum; however, hot H2 (v > 0) is detected in absorption against the Lyα emission line. We measure the column densities in eight individual rovibrational states, determining a total log10(N(H2)) = 17.9+0.6
−0.3 cm−2 with a thermal temperature of T(H2) = 2500+800
−700 K. The high temperature of the molecules, the relatively small H2 column density, and the high inclination of the AA Tauri disk suggest that the absorbing gas resides in an inner disk atmosphere. If the H2 and CO are cospatial within a molecular layer ∼0.6 AU thick, this region is characterized by

 ∼ 105 cm−3 with an observed 〈CO/H2〉 ratio of ∼0.4. We also find evidence for a departure from a purely thermal H2 distribution, suggesting that excitation by continuum photons and H2 formation may be altering the level populations in the molecular gas.
Yeast formin Bni1p has multiple localization regions that function in polarized growth and spindle orientation
Authors: Liu Wenyu , Santiago-Tirado Felipe H. , Bretscher Anthony
Published: December 2011

Formins are conserved proteins that assemble unbranched actin filaments in a regulated, localized manner. Budding yeast's two formins, Bni1p and Bnr1p, assemble actin cables necessary for polarized cell growth and organelle segregation. Here we define four regions in Bni1p that contribute to its localization to the bud and at the bud neck. The first (residues 1–333) requires dimerization for its localization and encompasses the Rho-binding domain. The second (residues 334–821) covers the Diaphanous inhibitory–dimerization–coiled coil domains, and the third is the Spa2p-binding domain. The fourth region encompasses the formin homology 1–formin homology 2–COOH region of the protein. These four regions can each localize to the bud cortex and bud neck at the right stage of the cell cycle independent of both F-actin and endogenous Bni1p. The first three regions contribute cumulatively to the proper localization of Bni1p, as revealed by the effects of progressive loss of these regions on the actin cytoskeleton and fidelity of spindle orientation. The fourth region contributes to the localization of Bni1p in tiny budded cells. Expression of mislocalized Bni1p constructs has a dominant-negative effect on both growth and nuclear segregation due to mislocalized actin assembly. These results define an unexpected complexity in the mechanism of formin localization and function.
InFiRe — a novel computational method for the identification of insertion sites in transposon mutagenized bacterial genomes
Authors: Shevchuk Olga , Roselius Louisa , Günther Gabriele , Klein Johannes , Jahn Dieter , Steinert Michael , Münch Richard
Published: December 2011

Motivation: InFiRe, Insertion Finder via Restriction digest, is a novel software tool that allows for the computational identification of transposon insertion sites in known bacterial genome sequences after transposon mutagenesis experiments. The approach is based on the fact that restriction endonuclease digestions of bacterial DNA yield a unique pattern of DNA fragments with defined sizes. Transposon insertion changes the size of the hosting DNA fragment by a known number of base pairs. The exact size of this fragment can be determined by Southern blot hybridization. Subsequently, the position of insertion can be identified with computational analysis. The outlined method provides a solid basis for the establishment of a new high-throughput technology.

Availability and implementation: The software is freely available on our web server at www.infire.tu-bs.de. The algorithm was implemented in the statistical programming language R. For the most flexible use, InFiRe is provided in two different versions. A web interface offers the convenient use in a web browser. In addition, the software and source code is freely available for download as R-packages on our website.

Contact:  m.steinert@tu-bs.de

Supplementary information:  Supplementary data are available at Bioinformatics online.
Biochemical analysis of infected cell polypeptide (ICP)0, ICP4, UL7 and UL23 incorporated into extracellular herpes simplex virus type 1 virions
Authors: Loret Sandra , Lippé Roger
Published: December 2011

Herpes simplex virus type 1 (HSV-1) capsids assemble in the nucleus but acquire their teguments from various cellular compartments. Unfortunately, little is known about their exact arrangement and when they coat the newly produced capsids. The complexity of the virions is further highlighted by our recent proteomics analysis that detected the presence of several novel or controversial components in extracellular HSV-1 virions. The present study probes the localization and linkage to the virus particles of some of these incorporated proteins. We confirm the recently reported tight association of infected cell polypeptide (ICP)0 with the capsid and show that this property extends to ICP4. We also confirm our proteomics data and show biochemically that UL7 and UL23 are indeed mature virion tegument components that, unlike ICP0 and ICP4, are salt-extractable. Interestingly, treatment with N-ethylmaleimide, which covalently modifies reduced cysteines, strongly prevented the release of UL7 and UL23 by salts, but did not perturb the interactions of ICP0 and ICP4 with the virus particles. This hitheir at distinct biochemical properties of the virion constituents and the selective implication of reduced cysteines in their organization and dynamics. Finally, the data revealed, by two independent means, the presence of ICP0 and ICP4 on intranuclear capsids, consistent with the possibility that they may at least partially be recruited to the virus particles early on. These findings add significantly to our understanding of HSV-1 virion assembly and to the debate about the incorporation of ICP0 and ICP4 in virus particles.
Cachrys pungens Jan inhibits human melanoma cell proliferation through photo‐induced cytotoxic activity
Authors: Menichini G. , Alfano C. , Provenzano E. , Marrelli M. , Statti G. A. , Menichini F. , Conforti F.
Published: December 2011

Objective:  To date, plants belonging to the genus Cachrys have not been amply studied. In the present study, aerial components of Cachrys pungens Jan from Italy, were examined to assess their free radical‐scavenging and antioxidant activity, and their phototoxicity on A375 melanoma cells. In view of potential pharmaceutical applications, a relationship between antioxidant, phototoxic activities and polyphenolic composition has also been investigated.

Materials and methods:  Content of sterols, terpenes, fatty acids and coumarins was assessed by gas chromatography–mass spectrometry and GC. Total phenolic content was also determined. Antioxidant activity of the methanol extract and fractions of C. pungens Jan was assessed using DPPH scavenging assay and β‐carotene bleaching test. Plant phototoxicity was also investigated in this human tumour cell line (amelanotic melanoma).

Results:  Analysis of the chloroform extract was particularly interesting, as it led to identification of many coumarins, of which five were linear and one angular furanocoumarins. Methanol and ethyl acetate fractions exhibited substantial antioxidant activity. Moreover, chloroform extract and isolated coumarin fraction had strong phototoxic activity on UVA‐induced A375 cells after irradiation at UVA dose of 1.08 J/cm.

Conclusions:  Plant‐derived natural compounds are an important source for development of cancer‐fighting drugs. This study has demonstrated strong phototoxic activity of the coumarin fraction of C. pungens, a plant which, to our knowledge, has never been studied before. This investigation offers a new perspective for developing other formulations potentially useful in photodynamic therapy for treatment of non‐melanoma skin cancers as well as melanomas.
Future prospects and challenges of vaccines against filariasis
Authors: BABAYAN S. A. , ALLEN J. E. , TAYLOR D. W.
Published: December 2011

Filarial infections remain a major public health and socio‐economic problem across the tropics, despite considerable effort to reduce disease burden or regionally eliminate the infection with mass drug administration programmes. The sustainability of these programmes is now open to question owing to a range of issues, not least of which is emerging evidence for drug resistance. Vaccination, if developed appropriately, remains the most cost‐effective means of long‐term disease control. The rationale for the feasibility of vaccination against filarial parasites including onchocerciasis (river blindness, Onchocerca volvulus) and lymphatic filariasis (Wuchereria bancrofti or Brugia malayi) is founded on evidence from both humans and animal models for the development of protective immunity. Nonetheless, enormous challenges need to be faced in terms of overcoming parasite‐induced suppression without inducing pathology as well as the need to both recognize and tackle evolutionary and ecological obstacles to successful vaccine development. Nonetheless, new technological advances in addition to systems biology approaches offer hope that optimal immune responses can be induced that will prevent infection, disease and/or transmission.
Inter‐laboratory comparison of different rapid methods for the detection of bacterial contamination in platelet concentrates
Authors: Vollmer T. , Hinse D. , Schottstedt V. , Bux J. , Tapernon K. , Sibrowski W. , Knabbe C. , Dreier J.
Published: December 2011

Background  Bacterial contamination of platelet concentrates still represents a major risk in transfusion medicine, and a variety of screening methods have been available to improve the safety of PCs. In the present study, the analytical quality of three different rapid screening methods (BactiFlow flow cytometry, Pan Genera Detection Assay, 23S rRNA RT‐PCR) was evaluated in an inter‐laboratory comparison in three different German blood services.

Methods  Samples were inoculated with different bacteria [Staphylococcus aureus, Staphylococcus epidermidis, Escherichia coli (two strains), Klebsiella pneumoniae (two strains), Enterobacter aerogenes (one strain), Serratia marcescens (one strain)] at different counts (4·5 × 103–4·5 × 108 CFU/ml) alternating with negative samples in one transfusion facility. Samples were blinded with a random order for each screening method, shipped to partners and analysed immediately after receipt with different rapid screening methods.

Results  The inter‐laboratory comparison revealed that the BactiFlow assay and 23S rRNA RT‐PCR‐screening detected all samples correctly (positive: 12/12, negative: 8/8). The Pan Genera Detection Assay test detected only four of the positive samples. Four of the non‐detected positive samples were below the assay’s detection limit. Another four inoculated samples with comparatively high bacteria counts were detected false negative (E. coli (two strains): 9·87 × 105 and 2·10 × 107 CFU/ml, respectively, K. pneumoniae: 4·79 × 106 CFU/ml, S. aureus: 6·03 × 105 CFU/ml). All rapid screening methods revealed no false‐positive results.

Conclusions  Both BactiFlow and 23S rRNA RT‐PCR demonstrated a high sensitivity to detecting bacterial contamination in PCs. The Pan Genera Detection Assay had some shortcomings regarding sensitivity, especially for the detection of Gram‐negative strains.