bluuebunny/crossref_metadata_2025 huggingface dataset:
Inequality and Regime Change: Democratic Transitions and the Stability of Democratic Rule
Authors: HAGGARD STEPHAN , KAUFMAN ROBERT R.
Published: August 2012

Recent work by Carles Boix and Daron Acemoglu and James Robinson has focused on the role of inequality and distributive conflict in transitions to and from democratic rule. We assess these claims through causal process observation, using an original qualitative dataset on democratic transitions and reversions during the “third wave” from 1980 to 2000. We show that distributive conflict, a key causal mechanism in these theories, is present in just over half of all transition cases. Against theoretical expectations, a substantial number of these transitions occur in countries with high levels of inequality. Less than a third of all reversions are driven by distributive conflicts between elites and masses. We suggest a variety of alternative causal pathways to both transitions and reversions.
The dietary flavonoids naringenin and quercetin acutely impair glucose metabolism in rodents possibly via inhibition of hypothalamic insulin signalling
Authors: Koch Christiane E. , Ganjam Goutham K. , Steger Juliane , Legler Karen , Stöhr Sigrid , Schumacher Daniela , Hoggard Nigel , Heldmaier Gerhard , Tups Alexander
Published: August 2012

Secondary metabolites of herbs and spices are widely used as an alternative strategy in the therapy of various diseases. The polyphenols naringenin, quercetin and curcumin have been characterised as anti-diabetic agents. Conversely,in vitro,naringenin and quercetin are described to inhibit phosphoinositide-3-kinase (PI3K), an enzyme that is essential for the neuronal control of whole body glucose homoeostasis. Using bothin vitroandin vivoexperiments, we tested whether the inhibitory effect on PI3K occurs in neurons and if it might affect whole body glucose homoeostasis. Quercetin was found to inhibit basal and insulin-induced phosphorylation of Akt (Ser473), a downstream target of PI3K, in HT-22 cells, whereas naringenin and curcumin had no effect. In Djungarian hamsters (Phodopus sungorus) naringenin and quercetin (10 mg/kg administered orally) diminished insulin-induced phosphorylation of Akt (Ser473) in the arcuate nucleus, indicating a reduction in hypothalamic PI3K activity. In agreement with this finding, glucose tolerance in naringenin-treated hamsters (oral) and mice (oral and intracerebroventricular) was reduced compared with controls. Dietary quercetin also impaired glucose tolerance, whereas curcumin was ineffective. Circulating levels of insulin and insulin-like growth factor-binding protein were not affected by the polyphenols. Oral quercetin reduced the respiratory quotient, suggesting that glucose utilisation was impaired after treatment. These data demonstrate that low doses of naringenin and quercetin acutely and potently impair glucose homoeostasis. This effect may be mediated by inhibition of hypothalamic PI3K signalling. Whether chronic impairments in glucose homoeostasis occur after long-term application remains to be identified.
Pathogen-group specific association betweenCXCR1polymorphisms and subclinical mastitis in dairy heifers
Authors: Verbeke Joren , Piepers Sofie , Peelman Luc , Van Poucke Mario , De Vliegher Sarne
Published: August 2012

The chemokine (C-X-C motif) receptor 1 (CXCR1) gene encodes the homonymous receptor for interleukin 8 (IL8) on polymorphonuclear neutrophilic leucocytes (PMNL). Binding causes migration from blood to milk, activation and prolonged survival of PMNL, a crucial process in the innate immune defence of the bovine mammary gland against invading mastitis-causing pathogens. The main objective of this study was to screen the entire coding region of theCXCR1gene for polymorphisms and to analyse their association with udder health of dairy heifers. One-hundred-and-forty Belgian Holstein heifers originating from 20 commercial dairy farms were genotyped by DNA sequencing. Detailed phenotypic data on udder health was available including quarter bacteriological culture results and somatic cell count (SCC) in early lactation and composite milk SCC during first lactation. In total, 16 polymorphisms (including 8 missense mutations) were detected. Polymorphism c.980A>G was associated with pathogen-group specific IMI: heifers with genotype AG were less likely to have an IMI due to major mastitis pathogens compared with heifers with genotype GG but did not have less IMI by coagulase-negative staphylococci, so-called minor pathogens.CXCR1genotype was neither associated with quarter SCC in early lactation nor with composite SCC during lactation. Although mastitis susceptibility is influenced by many factors, some genetic polymorphisms potentially have major effects on udder health of heifers, as was shown here. These results trigger us to further study the relationship betweenCXCR1polymorphisms and mastitis susceptibility in both observational and experimental trials.
Conceptual distance and word learning: Patterns of acquisition in Samoan–English bilingual children
Authors: HEMSLEY GAYLE , HOLM ALISON , DODD BARBARA
Published: August 2012

This study investigated cross-linguistic influence in acquisition of a second lexicon, evaluating Samoan–English sequentially bilingual children (initial mean age 4 ; 9) during their first 18 months of school. Receptive and Expressive Vocabulary tasks evaluated acquisition of four word types: cognates, matched nouns, phrasal nouns and holonyms. Each word type had varying phonological and conceptual difference between Samoan (L1) and English (L2). Results highlighted conceptual distance between L1 and L2 as a key factor in L2 lexical acquisition. The children acquired L2 lexical items earlier if their conceptual representation was similar to that of L1. Words with greater conceptual distance between L1 and L2 emerged more slowly. This suggests that L1 knowledge influences L2 lexical consolidation for sequential bilinguals. Words that require a conceptual shift from L1 take longer to consolidate and strengthen within the L2 lexicon.
Multispecies transport coupled to a first‐order reaction network in a double‐domain medium
Authors: Chen Huali , Ding Guoping , Han Weon Shik , Kim Kue‐Young , Park Eungyu
Published: August 2012

One‐dimensional analytical solutions for multispecies solute transport in a domain with two distinctive subdomains are developed based on exact interdomain boundary conditions. The derived solutions are tested through transient and steady state scenarios. In the global sensitivity analysis (SA) of the developed solutions, the influences of the up‐ and down‐gradient subdomains apportioned to the interfacial concentrations are 75.7 and 24.3%, respectively, while in the local SA, they are similar, at 65 and 35%, respectively. The overall SA results suggest that the common considerations of up‐ and down‐gradient influences are essential when the precision of the estimation is an important issue.
Upper ocean manifestations of a reducing meridional overturning circulation
Authors: Thomas M. D. , de Boer A. M. , Stevens D. P. , Johnson H. L.
Published: August 2012

Most climate models predict a slowing down of the Atlantic Meridional Overturning Circulation during the 21st century. Using a 100 year climate change integration of a high resolution coupled climate model, we show that a 5.3 Sv reduction in the deep southward transport in the subtropical North Atlantic is balanced solely by a weakening of the northward surface western boundary current, and not by an increase in the southward transport integrated across the interior ocean away from the western boundary. This is consistent with Sverdrup balance holding to a good approximation outside of the western boundary region on decadal time scales, and may help to spatially constrain past and future change in the overturning circulation. The subtropical gyre weakens by 3.4 Sv over the same period due to a weakened wind stress curl. These changes combine to give a net 8.7 Sv reduction in upper western boundary transport.
Reflection of solar wind protons on the Martian bow shock: Investigations by means of 3‐dimensional simulations
Authors: Richer E. , Chanteur G. M. , Modolo R. , Dubinin E.
Published: August 2012

The reflection of solar wind protons on the Martian bow shock (BS) is investigated by means of three‐dimensional simulation models. A two steps approach is adopted to allow a detailed analysis of the reflected population. Firstly, the 3‐dimensional hybrid model of Modolo et al. (2005) is used to compute a stationary state of the interaction of the solar wind (SW) with Mars. Secondly, the motion of test particles is followed in the electromagnetic field computed by the hybrid simulation meanwhile detection criteria defined to identify reflected protons are applied. This study demonstrates some effects of the large curvature of a planetary BS on the structure of the foreshock. Reflected protons encounter the BS in a region encompassing parts of the quasi‐perpendicular and quasi‐parallel shocks, and exit the shock mainly from the quasi‐parallel region. The energy spectrum of all reflected protons extends from 0 to almost 15keV. A virtual omnidirectional detector (VOD) is used to compute the local omnidirectional flux of reflected protons at various locations upstream of the BS. Spatial variations of this omnidirectional flux indicate the location and spatial extent of the proton foreshock and demonstrate its shift, increasing with the distance downstream, in the direction opposite to the motional electric field of the SW. Local energy spectra computed from the VOD observations demonstrate the existence of an energy gradient along the direction of the convection electric field.
Optically stimulated luminescence (OSL) as a chronometer for surface exposure dating
Authors: Sohbati Reza , Murray Andrew S. , Chapot Melissa S. , Jain Mayank , Pederson Joel
Published: August 2012

We pioneer a technique of surface‐exposure dating based upon the characteristic form of an optically stimulated luminescence (OSL) bleaching profile beneath a rock surface; this evolves as a function of depth and time. As a field illustration of this new method, the maximum age of a premier example of Barrier Canyon Style (BCS) rock art in Canyonlands National Park, Utah, USA, is constrained. The natural OSL signal from quartz grains is measured from the surface to a depth of >10 mm in three different rock samples of the Jurassic Navajo Sandstone. Two samples are from talus with unknown daylight exposure histories; one of these samples was exposed at the time of sampling and one was buried and no longer light exposed. A third sample is known to have been first exposed 80 years ago and was still exposed at the time of sampling. First, the OSL‐depth profile of the known‐age sample is modeled to estimate material‐dependent and environmental parameters. These parameters are then used to fit the model to the corresponding data for the samples of unknown exposure history. From these fits we calculate that the buried sample was light exposed for ∼700 years before burial and that the unburied sample has been exposed for ∼120 years. The shielded surface of the buried talus sample is decorated with rock art; this rock fell from the adjacent Great Gallery panel. Related research using conventional OSL dating suggests that this rockfall event occurred ∼900 years ago, and so we deduce that the rock art must have been created between ∼1600 and 900 years ago. Our results are the first credible estimates of exposure ages based on luminescence bleaching profiles. The strength of this novel OSL method is its ability to establish both ongoing and prior exposure times, at decadal to millennial timescales or perhaps longer (depending on the environmental dose rate) even for material subsequently buried. This has considerable potential in many archeological, geological and geo‐hazard applications.
Vaster, hotter, grainier
Authors: Jacobs Howy
Published: August 2012

In a light‐hearted preview of the Olympics, Howy asks which countries would win the medals if molecular biology was included as an official event.
Cerebral Blood Flow and Metabolism of Hyperperfusion after Cerebral Revascularization in Patients with Moyamoya Disease
Authors: Kaku Yasuyuki , Iihara Koji , Nakajima Norio , Kataoka Hiroharu , Fukuda Kenji , Masuoka Jun , Fukushima Kazuhito , Iida Hidehiro , Hashimoto Nobuo
Published: August 2012

In moyamoya disease (MMD), surgical revascularization may be complicated with postoperative hyperperfusion. We analyzed cerebral perfusion and metabolism using positron emission tomography (PET) or single-photon emission computed tomography (SPECT) before and after bypass surgery on 42 sides of 34 adult patients with MMD. In seven cases (16.7%) with symptomatic hyperperfusion, diagnosed by qualitative 123I-iodoamphetamine (IMP) SPECT, a subsequent PET study during postoperative subacute stages revealed significantly increased cerebral blood flow (CBF) from 34.1 ± 8.2 to 74.3 ± 12.8 mL/100 g per minute ( P < 0.01), a persistent increase in cerebral blood volume (CBV)from 5.77 ± 1.67 to 7.01 ± 1.44 mL/100 g and a significant decrease in oxygen extraction fraction (OEF) from 0.61 ± 0.09 to 0.40 ± 0.08 ( P < 0.01). Mean absolute CBF values during symptomatic hyperperfusion were more than the normal control +2 standard deviations, the predefined criteria of PET. Interestingly, two patients with markedly increased cerebral metabolic rate of oxygen (CMRO2) at hyperperfusion were complicated with postoperative seizure. Among preoperative PET parameters, increased OEF was the only significant risk factor for symptomatic hyperperfusion ( P < 0.05). This study revealed that symptomatic hyperperfusion in MMD is characterized by temporary increases in CBF >100% over preoperative values caused by prolonged recovery of increased CBV.
Farnesyl diphosphate synthase, the target for nitrogen-containing bisphosphonate drugs, is a peroxisomal enzyme in the model system Dictyostelium discoideum
Authors: Nuttall James M. , Hettema Ewald H. , Watts Donald J.
Published: August 2012

NBP (nitrogen-containing bisphosphonate) drugs protect against excessive osteoclast-mediated bone resorption. After binding to bone mineral, they are taken up selectively by the osteoclasts and inhibit the essential enzyme FDPS (farnesyl diphosphate synthase). NBPs inhibit also growth of amoebae of Dictyostelium discoideum in which their target is again FDPS. A fusion protein between FDPS and GFP (green fluorescent protein) was found, in D. discoideum, to localize to peroxisomes and to confer resistance to the NBP alendronate. GFP was also directed to peroxisomes by a fragment of FDPS comprising amino acids 1–22. This contains a sequence of nine amino acids that closely resembles the nonapeptide PTS2 (peroxisomal targeting signal type 2): there is only a single amino acid mismatch between the two sequences. Mutation analysis confirmed that the atypical PTS2 directs FDPS into peroxisomes. Furthermore, expression of the D. discoideum FDPS–GFP fusion protein in strains of Saccharomyces cerevisiae defective in peroxisomal protein import demonstrated that import of FDPS into peroxisomes was blocked in a strain lacking the PTS2-dependent import pathway. The peroxisomal location of FDPS in D. discoideum indicates that NBPs have to cross the peroxisomal membrane before they can bind to their target.
Protective role of AT2 and B1 receptors in kinin B2-receptor-knockout mice with myocardial infarction
Authors: Xu Jiang , Carretero Oscar A. , Zhu Liping , Shesely Edward G. , Rhaleb Nour-Eddine , Dai Xiangguo , Wang Luchen , Yang James J. , Yang Xiao-Ping
Published: August 2012

AT2Rs [AngII (angiotensin II) type 2 receptors] contribute to the cardioprotective effects of angiotensin II receptor blockers, possibly via kinins acting on the B1R (B1 receptor) and B2R (B2 receptor). Recent studies have shown that a lack of B2R up-regulates B1R and AT2R; however, the pathophysiological relevance of such an event remains unclear. We hypothesized that up-regulation of AT2R and B1R compensates for the loss of B2R. Blockade of AT2R and/or B1R worsens cardiac remodelling and dysfunction following MI (myocardial infarction) in B2R−/− (B2-receptor-knockout mice). B2R−/− mice and WT (wild-type) controls were subjected to sham MI or MI and treated for 4 weeks with (i) vehicle, (ii) a B1R-ant (B1R antagonist; 300 μg/kg of body weight per day), (iii) an AT2R-ant [AT2 receptor antagonist (PD123319); 20 mg/kg of body weight per day], or (iv) B1R-ant+AT2R-ant. B2R−/− mice had a greater MCSA (myocyte cross-sectional area) and ICF (interstitial collagen fraction) at baseline and after MI compared with WT controls. Cardiac function and increase in macrophage infiltration, TGFβ1 (transforming growth factor β1) expression and ERK1/2 (extracellular-signal-regulated kinase 1/2) phosphorylation post-MI were similar in both strains. Blockade of AT2R or B1R worsened cardiac remodelling, hypertrophy and dysfunction associated with increased inflammation and ERK1/2 phosphorylation and decreased NO excretion in B2R−/−mice, which were exacerbated by dual blockade of B1R and AT2R. No such effects were seen in WT mice. Our results suggest that, in the absence of B2R, both B1R and AT2R play important compensatory roles in preventing deterioration of cardiac function and remodelling post-MI possibly via suppression of inflammation, TGFβ1 and ERK1/2 signalling.
The effects of hydrodynamic interaction and inertia in determining the high-frequency dynamic modulus of a viscoelastic fluid with two-point passive microrheology
Authors: Córdoba Andrés , Schieber Jay D. , Indei Tsutomu
Published: August 2012

In two-point passive microrheology, a modification of the original one-point technique, introduced by Crocker et al. [Phys. Rev. Lett. 85, 888 (2000)]10.1103/PhysRevLett.85.888, the cross-correlations of two micron-sized beads embedded in a viscoelastic fluid are used to estimate the dynamic modulus of a material. The two-point technique allows for the sampling of larger length scales, which means that it can be used in materials with a coarser microstructure. An optimal separation between the beads exists at which the desired length and time scales are sampled while keeping a desired signal-to-noise-ratio in the cross-correlations. A large separation can reduce the effect of higher order reflections, but will increase the effects of medium inertia and reduce the signal-to-noise-ratio. The modeling formalisms commonly used to relate two-bead cross-correlations to G*(ω) neglect inertia effects and underestimate the effect of reflections. A simple dimensional analysis for a model viscoelastic fluid suggests that there exists a very narrow window of bead separation and frequency range where these effects can be neglected. Therefore, we consider both generalized data analysis and generalized Brownian dynamics (BD) simulations to examine the magnitude of these effects. Our proposed analysis relies on the recent analytic results of Ardekani and Rangel [Phys. Fluids 18, 103306 (2006)]10.1063/1.2363351 for a purely viscous fluid, which are generalized to linear viscoelastic fluids. Implementation requires approximations to estimate Laplace transforms efficiently. These approximations are then used to create generalized BD simulation algorithms. The data analysis formalism presented in this work can expand the region of separation between the beads and frequencies at which rheological properties can be accurately measured using two-point passive microrheology. Moreover, the additional physics introduced in the data analysis formalisms do not add additional significant computational costs.
Elevation angle alignment of quasi optical receiver mirrors of collective Thomson scattering diagnostic by sawtooth measurements
Authors: Moseev D. , Meo F. , Korsholm S. B. , Bindslev H. , Furtula V. , Kantor M. , Leipold F. , Michelsen P. K. , Nielsen S. K. , Salewski M. , Stejner M.
Published: August 2012

Localized measurements of the fast ion velocity distribution function and the plasma composition measurements are of significant interest for the fusion community. Collective Thomson scattering (CTS) diagnostics allow such measurements with spatial and temporal resolution. Localized measurements require a good alignment of the optical path in the transmission line. Monitoring the alignment during the experiment greatly benefits the confidence in the CTS measurements. An in situ technique for the assessment of the elevation angle alignment of the receiver is developed. Using the CTS diagnostic on TEXTOR without a source of probing radiation in discharges with sawtooth oscillations, an elevation angle misalignment of 0.9° was found with an accuracy of 0.25°.
Non-contact near-field underwater explosion induced shock-wave loading of submerged rigid structures: Nonlinear compressibility effects in fluid structure interaction
Authors: Ghoshal Ritwik , Mitra Nilanjan
Published: August 2012

A novel theory has been developed for underwater explosion induced shock wave loading considering nonlinear compressible medium both front and back of the free standing rigid plate. Both analytical formulation and numerical simulations have been performed in this manuscript for different type of shock loading profiles, different plate masses as well as different backing conditions of the plate. The results obtained have been asymptotically validated against existing theories in acoustic range. Impulse transmission, maximum momentum transfer, and cavitation inception have been determined for different cases and have been shown to be dependent on the fluid structure interaction parameter as well as the backing condition of the plate. Impulse design transmission curves have also been developed for plates of intermediate mass for different shock intensities and profiles thereby removing the need to perform numerical simulations. The major conclusions of the paper are that nonlinear compressibility and varying pressure back of the plate further enhance the beneficial effects of fluid-structure-interaction in reducing impulse transmitted to the structure. These results can be advantageously exploited for design and optimization of light weight underwater structures with increased blast resistance.
Note: Accounting for pressure effects on the calculated equilibrium structure of glassy GeSe2
Authors: Bouzid Assil , Massobrio Carlo
Published: August 2012

First-principles molecular dynamics (FPMD) data on the structural properties of glassy GeSe2 under ambient conditions are produced by carefully considering and minimizing the effect of a residual pressure on the periodic system. When compared to previous FPMD results, this strategy leads to an improved agreement between theory and neutron diffraction experiments.
Photoelectron spectroscopic study on the interaction of l-cysteine with the silver-based dental alloy
Authors: Ogawa Koji , Tsujibayashi Toru , Takahashi Kazutoshi , Azuma Junpei , Kamada Masao
Published: August 2012

The electronic structure of the silver-based dental alloy MC12 and its constituent metals and their interaction with l-cysteine have been investigated by ultraviolet photoelectron spectroscopy (UPS) using synchrotron radiation. The UPS spectra of l-cysteine on polycrystalline Ag, Cu, Pd, and Au substrates have been measured to understand the interaction of l-cysteine with the dental alloy surface. It was found that the electronic states of MC12 originate dominantly from Cu 3d states and Pd 4d states around the top of the valence bands, while the 4–7-eV electronic structure of MC12 originates from the Ag 4 d5/2 and Ag 4 d3/2 states. For l-cysteine, it was found that a new peak at 2 eV is observed for the thin films on Ag, Cu, and Au, while the structure around 2 eV on MC12 is similar to that on Pd. The shift of the 5-eV peak is observed for the thin films on Cu, Pd, and Au, but not on Ag and MC12. These results indicate that the interaction of l-cysteine with MC12 may be dominantly due to the Pd-S, Cu-S, and Ag-O bonds, while the contribution of the Ag-S bond is small.
Investigation on the optimized design of alternate-hole-defect for 2D phononic crystal based silicon microresonators
Authors: Wang Nan , Hsiao Fu-Li , Tsai J. M. , Palaniapan Moorthi , Kwong Dim-Lee , Lee Chengkuo
Published: August 2012

This paper shows the design, fabrication, and characterization of the Bloch-mode micromechanical resonators made by creating alternate defects to form a resonant cavity on a two-dimensional silicon phononic crystal slab of square lattice. The length of the resonant cavity (L) and the central-hole radius (r′) are varied to optimize the performance of the resonators. CMOS-compatible aluminium nitride is used as the piezoelectric material of the interdigital transducer to launch and detect acoustic waves. The extent of energy confinement within the cavity, as shown by the simulated displacement profiles of the resonators, agrees with the measured Q factors. We also quantitatively analysed the band structure of the proposed resonators and found that the Q factors are generally in an inverse relationship with the standard deviation of the band, due to the slow sound effect brought by flat bands which reduces the energy loss along the lateral direction (Y direction) and enhances the Q factor.
Emission spectra analysis of arc plasma for synthesis of carbon nanostructures in various magnetic conditions
Authors: Li Jian , Kundrapu Madhusudhan , Shashurin Alexey , Keidar Michael
Published: August 2012

Arc discharge supported by the erosion of anode materials is one of the most practical and efficient methods to synthesize various high-quality carbon nanostructures. By introducing a non-uniform magnetic field in arc plasmas, high-purity single-walled carbon nanotubes (SWCNT) and large-scale graphene flakes can be obtained in a single step. In this paper, ultraviolet-visible emission spectra of arc in different spots under various magnetic conditions are analyzed to provide an in situ investigation for transformation processes of evaporated species and growth of carbon nanostructures in arc. Based on the arc spectra of carbon diatomic Swan bands, vibrational temperature in arc is determined. The vibrational temperature in arc center was measured around 6950 K, which is in good agreement with our simulation results. Experimental and simulation results suggest that SWCNT are formed in the arc periphery region. Transmission electronic microscope and Raman spectroscope are also employed to characterize the properties of carbon nanostructures.
Investigating the role of hydrogen in silicon deposition using an energy-resolved mass spectrometer and a Langmuir probe in an Ar/H2 radio frequency magnetron discharge
Authors: Mensah S. L. , Naseem Hameed H. , Abu-Safe Husam , Gordon M. H.
Published: August 2012

The plasma parameters and ion energy distributions (IED) of the dominant species in an Ar-H2 discharge are investigated with an energy resolved mass spectrometer and a Langmuir probe. The plasmas are generated in a conventional magnetron chamber powered at 150 W, 13.56 MHz at hydrogen flow rates ranging from 0 to 25 sccm with a fixed argon gas flow rate of 15 sccm. Various Hn+, SiHn+, SiHn fragments (with n = 1, 2, 3) together with Ar+ and ArH+ species are detected in the discharge. The most important species for the film deposition is SiHn (with n = 0, 1, 2). H fragments affect the hydrogen content in the material. The flux of Ar+ decreases and the flux of ArH+ increases when the hydrogen flow rate is increased; however, both fluxes saturate at hydrogen flow rates above 15 sccm. Electron density, ne, electron energy, Te, and ion density, ni, are estimated from the Langmuir probe data. Te is below 1.2 eV at hydrogen flow rates below 8 sccm, and about 2 eV at flow rates above 8 sccm. ne and ni decrease with increased hydrogen flow but the ratio of ni to ne increases. The formation of H+ ions with energies above 36 eV and electrons with energies greater than 2 eV contributes to the decrease in hydrogen content at hydrogen flow rates above 8 sccm. Analysis of the IEDs indicates an inter-dependence of the species and their contribution to the thin film growth and properties.
From landing lights to mimicry: the molecular regulation of flower colouration and mechanisms for pigmentation patterning
Authors: Davies Kevin M. , Albert Nick W. , Schwinn Kathy E.
Published: August 2012

Flower colour is a key component for plant signaling to pollinators and a staggering variety of colour variations are found in nature. Patterning of flower colour, such as pigment spots or stripes, is common and is important in promoting pollination success. Developmentally programmed pigmentation patterns are of interest with respect to the evolution of specialised plant–pollinator associations and as models for dissecting regulatory signaling in plants. This article reviews the occurrence and function of flower colour patterns, as well as the molecular genetics of anthocyanin pigmentation regulation. The transcription factors controlling anthocyanin biosynthesis have been characterised for many species and an ‘MBW’ regulatory complex of R2R3MYB, bHLH and WD-Repeat proteins is of central importance. In particular, R2R3MYBs are key determinants of pigmentation intensity and patterning in plants. Progress is now being made on how environmental or developmental signal pathways may in turn control the production of the MBW components. Furthermore, additional regulatory proteins that interact with the MBW activation complex are being identified, including a range of proteins that repress complex formation or action, either directly or indirectly. This review discusses some of the recent data on the regulatory factors and presents models of how patterns may be determined.
Environmental variability and acoustic signals: a multi-level approach in songbirds
Authors: Medina Iliana , Francis Clinton D.
Published: August 2012

Among songbirds, growing evidence suggests that acoustic adaptation of song traits occurs in response to habitat features. Despite extensive study, most research supporting acoustic adaptation has only considered acoustic traits averaged for species or populations, overlooking intraindividual variation of song traits, which may facilitate effective communication in heterogeneous and variable environments. Fewer studies have explicitly incorporated sexual selection, which, if strong, may favour variation across environments. Here, we evaluate the prevalence of acoustic adaptation among 44 species of songbirds by determining how environmental variability and sexual selection intensity are associated with song variability (intraindividual and intraspecific) and short-term song complexity. We show that variability in precipitation can explain short-term song complexity among taxonomically diverse songbirds, and that precipitation seasonality and the intensity of sexual selection are related to intraindividual song variation. Our results link song complexity to environmental variability, something previously found for mockingbirds (Family Mimidae). Perhaps more importantly, our results illustrate that individual variation in song traits may be shaped by both environmental variability and strength of sexual selection.
Proximity data-loggers increase the quantity and quality of social network data
Authors: Ryder Thomas B. , Horton Brent M. , van den Tillaart Mike , Morales Juan De Dios , Moore Ignacio T.
Published: August 2012

Social network analysis is an ideal quantitative tool for advancing our understanding of complex social behaviour. However, this approach is often limited by the challenges of accurately characterizing social structure and measuring network heterogeneity. Technological advances have facilitated the study of social networks, but to date, all such work has focused on large vertebrates. Here, we provide proof of concept for using proximity data-logging to quantify the frequency of social interactions, construct weighted networks and characterize variation in the social behaviour of a lek-breeding bird, the wire-tailed manakin,Pipra filicauda. Our results highlight how this approach can ameliorate the challenges of social network data collection and analysis by concurrently improving data quality and quantity.
Plasmodium
infection decreases fecundity and increases survival of mosquitoes
Authors: Vézilier J. , Nicot A. , Gandon S. , Rivero A.
Published: August 2012

Long-lived mosquitoes maximize the chances of
Plasmodium
transmission. Yet, in spite of decades of research, the effect of
Plasmodium
parasites on mosquito longevity remains highly controversial. On the one hand, many studies report shorter lifespans in infected mosquitoes. On the other hand, parallel (but separate) studies show that
Plasmodium
reduces fecundity and imply that this is an adaptive strategy of the parasite aimed at redirecting resources towards longevity. No study till date has, however, investigated fecundity and longevity in the same individuals to see whether this prediction holds. In this study, we follow for both fecundity and longevity in
Plasmodium-
infected and uninfected mosquitoes using a novel, albeit natural, experimental system. We also explore whether the genetic variations that arise through the evolution of insecticide resistance modulate the effect of
Plasmodium
on these two life-history traits. We show that (i) a reduction in fecundity in
Plasmodium-
infected mosquitoes is accompanied by an increase in longevity; (ii) this increase in longevity arises through a trade-off between reproduction and survival; and (iii) in insecticide-resistant mosquitoes, the slope of this trade-off is steeper when the mosquito is infected by
Plasmodium
(cost of insecticide resistance).
In Vivo Administration of Recombinant Alphavirus into Rodents
Authors: Lundstrom Kenneth
Published: August 2012

The alphaviruses Semliki Forest virus (SFV) and Sindbis virus (SIN) have been used frequently as expression vectors in vitro and in vivo. Usually, these systems consist of replication-deficient vectors that require a helper vector for packaging of recombinant particles. Replication-proficient vectors have also been engineered. Alphaviral vectors can be used as nucleic-acid-based vectors (DNA and RNA) or infectious particles. High-titer viral production is achieved in <2 d. The broad host range of alphaviruses facilitates studies in mammalian and nonmammalian cell lines, primary cells in culture, and in vivo. The strong preference for expression in neuronal cells has made alphaviruses particularly useful in neurobiological studies. Unfortunately, their strong cytotoxic effect on host cells, relatively short-term transient expression patterns, and the reasonably high cost of viral production remain drawbacks. However, novel mutant alphaviruses have shown reduced cytotoxicity and prolonged expression. This protocol describes stereotactic microinjection of recombinant alphavirus into rodents. Administration can be performed without any purification or concentration of viral stocks. However, filter-sterilization is recommended to ensure that cell debris or other contaminants are not present.
Labeling Golgi with Fluorescent Ceramides
Authors: Chazotte Brad
Published: August 2012

The Golgi may be considered a principal organizer of macromolecular traffic in the cell because many molecules, such as secreted proteins, glycoproteins, glycolipids, and plasma membrane glycoproteins, pass through the Golgi during their maturation. The fluorescent probes used to tag the Golgi make use of this function for labeling by using a fluorescent ceramide. In this protocol, two probes for labeling the Golgi are presented: a classic NBD-ceramide and a BODIPY-ceramide probe that is more resistant to photobleaching.
Construction, Alignment, and Implementation of an Acousto-Optical Deflector-Based System for Patterned Uncaging with Ultraviolet Light
Authors: Civillico Eugene F. , Shoham Shy , O'Connor Daniel H. , Sarkisov Dmitry V. , Wang Samuel S.-H.
Published: August 2012

The method of patterned photoactivation is a natural fit for the study of neuronal dendritic integration. Photoactivatable molecules that influence a wide range of extracellular and intracellular neurophysiological functions are available. The choice of photosensitive molecules depends on the research question and will influence the design of the experimental apparatus. An acousto-optical deflector (AOD)-based system can be used for rapid ultraviolet (UV) photolysis in arbitrary spatial and temporal patterns. Photolysis-activated “caged” diffusible molecules or newer light-sensitive membrane proteins can be used in this system. This protocol describes the addition of a UV beam for uncaging to a homebuilt two-photon microscope. The goal is to get UV light from the light source (laser) to the approximate center of the objective's back aperture, passing through a pair of perpendicularly oriented AODs along the way. The protocol also describes the fine alignment of the UV beam and the implementation of AOD-based beam steering. Performing the final alignment with the beam passing through the AODs will ensure that the system is optimized for the idiosyncrasies of the crystals.
Acousto-Optical Deflector-Based Patterned Ultraviolet Uncaging of Neurotransmitter for the Study of Neuronal Integration
Authors: Civillico Eugene F. , Shoham Shy , O'Connor Daniel H. , Sarkisov Dmitry V. , Wang Samuel S.-H.
Published: August 2012

The method of patterned photoactivation is a natural fit for the study of neuronal dendritic integration. Photoactivatable molecules that influence a wide range of extracellular and intracellular neurophysiological functions are available. The choice of photosensitive molecules depends on the research question and will influence the design of the experimental apparatus. This article describes an acousto-optical deflector (AOD)-based system for rapid ultraviolet (UV) photolysis in arbitrary spatial and temporal patterns. Some basics of caged neurotransmitters and the theory of operation of AODs are covered, as are descriptions for implementing the system.
Knowledge of genetics and the role of the nurse in genetic health care: a survey of Italian nurses
Authors: Godino Lea , Turchetti Daniela , Skirton Heather
Published: August 2012

Aim

To report a study of Italian nurses' understanding of genetics. The objectives were to explore nurses' basic knowledge of genetics, their perceptions of the relevance of genetics and their opinions about the role of the genetic nurse.

Background

As the knowledge of the genetic basis for disease has developed, pressure to give genetic healthcare services for a larger number of individuals has increased.

Specialist genetic nurses currently work in many countries; however, there are very few specialist genetic nurses in Italy and the preparedness of Italian nurses to give care for people with or at risk for genetic conditions is unclear.

Design

A cross‐sectional survey.

Methods

The survey was administered over 3 months during 2011. Registered Nurses aged 21–65 years were recruited via the website of the Italian nurse registration body, social network sites, hand‐distributed flyers and email. Three hundred and eight‐five (90%) nurses completed the survey. Data were analysed using descriptive statistics, Kruskal‐Wallis tests for distribution and Spearman's Rho analysis of correlations.

Results

The majority of respondents correctly answered at least four of five genetics knowledge questions. There were no statistically significant difference between knowledge scores when analysed according to age, but scores were positively correlated with higher academic qualifications and previous genetics education. A minority of respondents believed genetics was highly relevant to the nursing role.

Conclusion

It is essential to ensure that educational provision for nurses includes not only the genetic concepts underpinning health and disease, but also how these are applied to nursing care.
Self‐reported health and physical activity among community mental healthcare users
Authors: LASSENIUS O. , ÅKERLIND I. , WIKLUND‐GUSTIN L. , ARMAN M. , SÖDERLUND A.
Published: August 2012

Accessible summary

The aim of the study was to get a picture of the self‐reported health and physical activity among persons with psychiatric disabilities who were community healthcare users in a community in Sweden. This was carried out through a questionnaire.

Out of 319 eligible persons, 103 persons answered the questionnaire. The answers from the questionnaire showed that this group has a high impact of unhealthy risk factors, such as excess weight, low amount of physical activity and a low perceived state of health.

About 20% of the participants wanted help with filling out the questionnaire. This was because of difficulties apprehending some of the questions. Helping these participants with the answering process showed complications with this given questionnaire but also highlighted the special considerations related to cognitive difficulties entailed with mental illness. This underlines the need for reflection upon what questions we ask, to whom and how.

The results of this study point out that persons with psychiatric disabilities constitute a vulnerable group, in need of adequate health‐promoting activities based upon the individual's conditions.

The aim of the study was to survey the self‐reported health and physical activity in a sample of community mental healthcare users in a city of Sweden. The study was conducted through a cross‐sectional design with participants requested to fill out a self‐report questionnaire. Participants (n = 103) were persons with psychiatric disabilities living in residential psychiatric settings and/or participating in daily activities provided by community mental healthcare services. The results showed that the group is affected with serious risk factors, such as high body mass index, low rated extent and frequency of physical activity and low self‐estimated general state of health. Even though some difficulties associated with the answering process of this questionnaire emerged, these self‐reported results clearly confirm the fact that persons with psychiatric disabilities constitute a vulnerable group in need for health‐promoting caring activities and interventions.
Single‐session ureteroscopy with holmium laser lithotripsy for multiple stones
Authors: Takazawa Ryoji , Kitayama Sachi , Tsujii Toshihiko
Published: August 2012

Multiple stones are found in 20–25% of patients with urolithiasis. The stone multiplicity is a powerful adverse factor influencing the treatment outcome after shockwave lithotripsy, although guidelines for the treatment of multiple stones have not been well established yet. Herein we report our most recent experience of a single‐session ureteroscopy for multiple stones. Between September 2008 and December 2011, 51 patients with multiple stones (total 146 stones) in different locations (37unilateral, 14 bilateral) underwent a total of 65 ureteroscopic procedures. Operative time, stone‐free rates and complications were evaluated. Stone‐free status was defined as no fragments in the ureter and the absence of >2 mm fragments in the kidney. The mean stone number per patient was 2.9 ± 1.7 and the mean stone burden (cumulative stone length) was 21.5 ± 11.6 mm. The mean number of procedures was 1.3 ± 0.6. Overall, the stone‐free rate after a single session was 80% (41/51). In patients with stone burden <20 mm and ≥20 mm, stone‐free rates after a single session were 92% (23/25) and 69% (18/26), respectively. Multivariate analysis showed that the stone burden and the presence of impacted stones were the factors significantly influencing the treatment outcome. Stone location did not have a strong influence on the outcome. No major intraoperative complications were identified. Our findings suggest that ureteroscopy is an efficient treatment for multiple stones. For patients with stone burden <20 mm, either unilaterally or bilaterally, a single session of ureteroscopy is a favorable treatment option with a high stone‐free rate.
Reanimating Anarchist Geographies: A New Burst of Colour
Authors: Springer Simon , Ince Anthony , Pickerill Jenny , Brown Gavin , Barker Adam J.
Published: August 2012

Abstract:  The late nineteenth century saw a burgeoning of geographical writings from influential anarchist thinkers like Peter Kropotkin and Élisée Reclus. Yet despite the vigorous intellectual debate sparked by the works of these two individuals, following their deaths anarchist ideas within geography faded. It was not until the 1970s that anarchism was once again given serious consideration by academic geographers who, in laying the groundwork for what is today known as “radical geography”, attempted to reintroduce anarchism as a legitimate political philosophy. Unfortunately, quiet followed once more, and although numerous contemporary radical geographers employ a sense of theory and practice that shares many affinities with anarchism, direct engagement with anarchist ideas among academic geographers have been limited. As contemporary global challenges push anarchist theory and practice back into widespread currency, geographers need to rise to this occasion and begin (re)mapping the possibilities of what anarchist perspectives might yet contribute to the discipline.
Philosophical Aspects of Quantum Field Theory: II
Authors: Ruetsche Laura
Published: August 2012

According to a regnant criterion of physical equivalence for quantum theories, a quantum field theory (QFT) typically admits continuously many physically inequivalent realizations. This, the second of a two‐part introduction to topics in the philosophy of QFT, continues the investigation of this alarming circumstance. It begins with a brief catalog of quantum field theoretic examples of this non‐uniqueness, then presents the basics of the algebraic approach to quantum theories, which discloses a structure common even to ‘physically inequivalent’ realizations of a QFT. Finally, it introduces and evaluates a handful of strategies for interpreting quantum theories in the face of the non‐uniqueness of their Hilbert space representations.
Philosophical Aspects of Quantum Field Theory: I
Authors: Ruetsche Laura
Published: August 2012

This is the first of a two‐part introduction to some interpretive questions that arise in connection with quantum field theories (QFTs). Some of these questions are continuous with those familiar from the discussion of ordinary non‐relativistic quantum mechanics (QM). For example, questions about locality can be rigorously posed and fruitfully pursued within the framework of QFT. A stark disanalogy between QFTs and ordinary QM – the former, but not the latter, typically admit infinitely many putatively physically inequivalent realizations – prompts relatively novel questions, questions about how to understand and adjudicate different strategies for equipping quantum theories with content. Part I sketches the fate of locality and related notions in QFT, then documents the non‐uniqueness unprecedented in ordinary QM but rampant in QFT. Part II presents foundations issues raised by non‐uniqueness.