bluuebunny/crossref_metadata_2025 huggingface dataset:
Pulse duration impact on laser structured ZnO:Al
Authors: Sämann Marc , Schubert Markus B.
Published: September 2011

We demonstrate a laser structuring process for aluminum doped ZnO with a line‐shaped Nd:YAG ultraviolet laser. This process yields a pyramid‐like surface texture with structure depths of d = 1.3 µm, which enhances light trapping in solar cells by diffraction of near infrared radiation. We investigate the impact of laser pulse duration from $ 25\,{\rm ns}\; \le \; \tau _{\rm P} \; \le \;60\;{\rm ns} $ on the optical transmittance and electrical conductivity of laser structured ZnO:Al. Formation of the surface texture proceeds via capillary waves. Increasing laser pulse duration causes oxygen effusion during the melt phase, and thereby impairs charge carrier mobility of the laser structured films.

magnified image

a) Line‐focused Nd:YAG UV laser locally melts ZnO:Al and b) induces capillary waves. c) Line‐scanning forms wave structures, d) second scan after 90° rotation yields 2D pattern.

(© 2011 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Magnetic vortex excitation dependence on the magnetic free layer and size of spin‐valve nanocontacts
Authors: Eggeling Moritz , Dimopoulos Theodoros , Heer Rudolf , Brückl Hubert
Published: September 2011

In this Letter we report on the spin‐torque‐driven magnetic switching and dynamic excitations in spin‐valve, circular nanocontacts, incorporating an unpinned CoFe/Ru/CoFe artificial antiferromagnet as polarizer. Our investigation concentrates on the influence of the magnetic free layer moment and of the nanocontact size on these spin‐torque related phenomena. Two multilayers are therefore investigated, one with an amorphous CoFeB and the other with a CoFe/CoFeB free layer. The nanocontact radii range from 40–130 nm. Both multilayers show clear current‐induced magnetic switching for small in‐plane magnetic fields. On the other hand, sub‐gigahertz dynamic spectra, related to magnetic vortex precession, are only observed for multilayers employing the CoFeB free layer and only for contact radii below 100 nm. The current and frequency dependence of the oscillation on the point contact radius and magnetic field is discussed. Multiple excitation modes are shown to exist at zero or small magnetic fields as a result of a highly inhomogeneous magnetic state below the nanocontact. (© 2011 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Antioxidant Activity of Puha (Sonchus oleraceus L.) as Assessed by the Cellular Antioxidant Activity (CAA) Assay
Authors: McDowell Arlene , Thompson Scott , Stark Mirjam , Ou Zong‐Quan , Gould Kevin S.
Published: September 2011

There is considerable interest in antioxidant dietary components that can be protective against degenerative diseases in humans. Puha (Sonchus oleraceus L.) is a rich source of polyphenols, and exhibits strong antioxidant activity as measured by the 2,2‐diphenylpicrylhydrazyl (DPPH) assay. However, the potential of puha to protect against degenerative diseases requires that low molecular weight antioxidants (LMWA) are absorbed by, and active in, human cells. The cellular antioxidant activity (CAA) assay was used to investigate the antioxidant activity of puha leaf extracts. Preparation methods of freezing and freeze‐drying reduced the total polyphenolic content compared with fresh puha, but did not affect the LMWA potential as determined by the DPPH assay. The IC50 values were 0.012 ± 0.003 mg/mL and 0.010 ± 0.005 mg/mL for freeze‐dried and fresh puha leaves, respectively. Using the CAA assay, it was shown that LMWAs from foliar extracts of puha were effectively absorbed into HepG2 cells, and exerted antioxidant activity at levels comparable to those of extracts from blueberry fruits, the much‐touted antioxidant superfood. Methylene blue staining of HepG2 cells indicated that puha extracts were not cytotoxic at concentrations below 100 mg DW/mL. The data indicate the potential of puha as a nutraceutical supplement for human health. Copyright © 2011 John Wiley & Sons, Ltd.
Polymer‐Coated Nanoparticles: A Universal Tool for Biolabelling Experiments
Authors: Zhang Feng , Lees Emma , Amin Faheem , Rivera_Gil Pilar , Yang Fang , Mulvaney Paul , Parak Wolfgang J.
Published: September 2011

Water solubilization of nanoparticles is a fundamental prerequisite for many biological applications. To date, no single method has emerged as ideal, and several different approaches have been successfully utilized. These ‘phase‐transfer’ strategies are reviewed, indicating key advantages and disadvantages, and a discussion of conjugation strategies is presented. Coating of hydrophobic nanoparticles with amphiphilic polymers provides a generic pathway for the phase transfer of semiconductor, magnetic, metallic, and upconverting nanoparticles from nonpolar to polar environments. Amphiphilic polymers that include maleimide groups can be readily functionalized with chemical groups for specific applications. In the second, experimental part, some of the new chemical features of such polymer‐capped nanoparticles are demonstrated. In particular, nanoparticles to which a pH sensitive fluorophore has been attached are described, and their use for intracellular pH‐sensing demonstrated. It is shown that the properties of analyte‐sensitive fluorophores can be tuned by using interactions with the underlying nanoparticles.
Metastable Bi8Ni8S by Reductive Pseudomorphosis of Bi8Ni8SI2
Authors: Kaiser Martin , Isaeva Anna , Skrotzki Richard , Schwarz Ulrich , Ruck Michael
Published: September 2011

The bimetallic subsulfide Bi8Ni8S was synthesized by reduction of Bi8Ni8SI2withn‐BuLi. Bi8Ni8S is metastable and decomposes exothermically at about 180 °C. In a pseudomorphosis, the shiny black crystals of the precursor were preserved, while the iodide ions were extracted and the pre‐formed$\rm^1_\infty$[Bi8Ni8S] fragments rearranged into a pseudo‐hexagonal rod packing [space groupPbam,a= 1750.14(7) pm,b= 1007.7(2) pm,c= 419.6(3) pm]. The rods have an effective diameter of about 1 nm and consist of an outer octagonal tube of bismuth atoms and an inner octagonal tube of nickel atoms. This arrangement markedly resembles the columnar Ta4Te4Si structure type. The difference comes with the disulfide groups that reside on the central axis. Interatomic distances inside the rods are almost not affected by the reduction, and thus the electronic band structure is not much altered. Yet, the additional electrons raise the Fermi level into a local maximum of the density of states and occupy predominantly antibonding Ni–Ni and S–S states. The dominant Bi–Ni multicenter bonding is accompanied by localized two‐center bonds between nickel atoms. The charges of the nickel atoms as well as ELI‐D basin populations of Ni–Ni and Ni–Bi bonds change considerably, indicating that the tube is (un)charging quite flexibly and acts as an electron reservoir. In contrast to the iodide precursor, the weak Pauli paramagnetism of Bi8Ni8S is slightly enhanced and spin correlations are observed below 20 K.
Experiments in program verification using Event-B
Authors: Hallerstede Stefan , Leuschel Michael
Published: September 2011

The Event-B method can be used to model all sorts of discrete event systems, among them sequential programs. In this article we describe our experiences with using Event-B by way of two examples. We present a simple model of a factorial program, explaining the method, and a more intricate model of the Quicksort algorithm, providing some insights into strengths and weaknesses of Event-B. The two models are interspersed with our observations and some suggestions of how, we believe, Event-B could evolve. This evaluation of Event-B is intended to serve for determining directions for the evolution of Event-B and judging progress. It is our hope that the observations and suggestions can also be put to use for similar modelling formalisms, such as Z, ASM or VDM.
Polyacrylamide Gel Injections for Breast Augmentation: Management of Complications in 106 Patients, a Multicenter Study
Authors: Unukovych Dmytro , Khrapach Vasyl , Wickman Marie , Liljegren Annelie , Mishalov Volodymyr , Patlazhan Gennadiy , Sandelin Kerstin
Published: September 2011

Background

Polyacrylamide gel (PAAG) was first manufactured in Ukraine in the late 1980s and introduced as a biomaterial for “breast augmentation without surgery.” Since it is prohibited in most countries, PAAG injections are rare nowadays, but their consequences and long‐term complications can be crucial.

Methods

We identified 106 patients consecutively operated on for PAAG complications at three teaching Ukrainian hospitals between 1998 and 2009. All relevant sociodemographic, clinical, and treatment characteristics were collected. Forty‐five (42%) patients were available for clinical follow‐up.

Results

The majority (88%) had had bilateral PAAG injections. The mean volume of injected PAAG was 230 ml/breast (range = 50–400). Mean age at injection was 29 years (range = 17–49) and the mean time from the injection to complications was 6.1 years (SD = 4.1). Symptoms preceding debridement were pain in 85 patients (80%), breast hardening in 79 (74%), breast deformity in 77 (73%), lumps in 57 (54%), gel migration in 39 (37%), fistulas in 17 (16%), and gel leakage in 12 (11%). The surgical interventions in 199 breasts included gel evacuation alone in 107 (54%) or in combination with partial mastectomy in 65 (33%), partial mastectomy and partial pectoralis muscle resection in 12 (6%), or subcutaneous mastectomy in 15 (7%). Of the 199 operated breasts, 86 (43%) immediate and 58 (29%) delayed implant‐based breast reconstructions were performed.

Conclusion

Injections of PAAG can cause irreversible damage to the breast necessitating complex debridement procedures, even mastectomy and breast reconstruction. Despite numerous surgical interventions, gel remnants are still found on subsequent breast imaging. Although PAAG is prohibited in many countries, different types of injections with unknown long‐term effects are currently being used. Making the public aware of the problems of injectables for breast augmentation is warranted.
Neue ökonomische Kerne in nordrhein-westfälischen Stadtregionen: Postsuburbanisierung und Restrukturierung kernstädtischer Räume
Authors: Knapp Wolfgang , Volgmann Kati
Published: September 2011

The newest transformation of city regions is characterized by both the emerging postsuburban development in the urban periphery and the restructuring of the city. New economic cores (conceptualized as concentrations of employment or enterprises) are emerging around the traditional central district of the city and in postsuburbia together with new city-regional relations based on the division of labor. For the case of the city regions of North-Rhine Westphalia, this article examines this transformation using different approaches. We proceed from the assumption that the new economic cores within the city regions of North Rhine-Westphalia tend to be more autonomously in their function and range of responsibilities to traditional and new cores of the central city and that new relations between the cores exist at different scales.
Mixing events in a stratified jet subject to surface wind and buoyancy forcing
Authors: Pham Hieu T. , Sarkar Sutanu
Published: September 2011

The fine-scale response of a subsurface stable stratified jet subject to the forcing of surface wind stress and surface cooling is investigated using direct numerical simulation. The initial velocity profile consists of a symmetric jet located below a surface layer driven by a constant wind stress. The initial density profile is well-mixed in the surface layer and linearly stratified in both upper and lower flanks of the jet. The minimum value of the gradient Richardson number in the upper flank of the jet exceeds the critical value of 0.25 for linear shear instability. Broadband finite-amplitude fluctuations are introduced to the surface layer to initiate the simulation. Turbulence is generated in the surface layer and deepens into the jet upper flank. Internal waves generated by the turbulent surface layer are observed to propagate downward across the jet. The momentum flux carried by the waves is significantly smaller than the Reynolds shear stress extracted from the background velocity. The wave energy flux is also smaller than the turbulence production by mean shear. Ejections of fluid parcels by horseshoe-like vortices cause intermittent patches of intense dissipation inside the jet upper flank where the background gradient Richardson number is larger than 0.25. Drag due to the wind stress is smaller than the drag caused by turbulent stress in the flow. Analysis of the mean and turbulent kinetic energy budgets suggests that the energy input by surface forcing is considerably smaller than the energy extracted from the initially imposed background shear in the surface layer.
Turbulent spots in oscillatory boundary layers
Authors: Mazzuoli Marco , Vittori Giovanna , Blondeaux Paolo
Published: September 2011

Detailed knowledge of the dynamics of vortex structures in an oscillatory boundary layer is essential for the correct modelling of transport processes in many engineering problems and, in particular, of the pick-up and transport of sediments at the bottom of sea waves. In the present contribution, the formation of turbulent spots in an oscillatory boundary layer is investigated by means of direct numerical simulations. Two of the laboratory experiments of Carstensen, Sumer and Fredsøe are reproduced and, after a comparison of the numerical results with laboratory measurements, a detailed and quantitative characterization of the turbulent spots is also given on the basis of further simulations. The speeds of the head (${u}_{1H} $) and tail (${u}_{1T} $) of the spots are found to scale with the instantaneous free stream velocity ${U}_{e} $ and to be similar to those observed in steady boundary layers. The ratios ${u}_{1H} / {U}_{e} $ and ${u}_{1T} / {U}_{e} $ seem to increase with the Reynolds number (${R}_{\delta } $) while the streamwise expansion rate of the spots appears to be independent of ${R}_{\delta } $.
Scandal Fatigue? Scandal Elections and Satisfaction with Democracy in Western Europe, 1977–2007
Authors: Kumlin Staffan , Esaiasson Peter
Published: September 2011

Elections involving a major scandal were unusual in the late 1970s, but today nearly half are so affected. Multilevel analyses of Eurobarometer data reveal that scandal elections once had negative net effects on satisfaction with democracy. However, as scandals have become more common, the negative effect has withered away. This ‘scandal fatigue’ process appears driven by changes in scandal material, rather than by changes in citizens’ reactions to a given type of material. Scandals involving several politicians and parties still really matter, but these have not become markedly more common. The possibility that the increasing incidence of scandals has created a morecriticalapproach to scandal material is discussed. As scandals accumulate, citizens may become more prone to ponder the relevance of a story and the motives of the messenger.
The Christmas Season and the Protestant Churches in England, c. 1870–1914
Authors: ARMSTRONG NEIL
Published: September 2011

Histories of the English Christmas tend to downplay the role of religion in the development of the modern festival. This article examines the place of religion in the popular celebration of Christmas, as well as the provision of worship offered by the Protestant Churches during the festive season. It argues that although some churchmen viewed Christmas pessimistically as part of a broader battle between sacred and secular, the Churches played an important role in the expansion of the urban public culture of Christmas in the late nineteenth century, whilst the doctrine of the incarnation provided a religious framework for the celebration of childhood and domesticity that the festival had come to embody.
Credibility talk in public diplomacy
Authors: MOR BEN D.
Published: September 2011

‘Politics has become a contest of competitive credibility’, argued Nye inSoft Power. Indeed, being perceived as honest and reliable is a necessary condition for obtaining and holding the attention of target audiences, as well as for effective persuasion, which is the objective of strategic communication. This task has become all the more difficult with the explosion of information sources and the discreditation efforts of opponents, but it is an essential element in the conduct of public diplomacy. How, then, do states and other international actors go about establishing their credibility while undermining that of opponents? This article employs rhetorical theory, impression management theory, and account theory to situate contests of credibility within the broader context of the accountability of social conduct. The theoretical part discusses the rhetorical strategies that actors use to credit their accounts and discredit those of their rivals. The empirical part addresses the debate between Israel and human rights groups over the Qana bombing incident of July 2006. The analysis of the blame imposition strategies used by Amnesty International and Human Rights Watch and the accounts offered by Israel, indicates the range and variability of credibility talk and the rules for crediting accounts that underlie it.
Fishing for a solution: can collaborative resource management reduce poverty and support conservation?
Authors: SOLOMON JENNIFER , JACOBSON SUSAN K. , LIU IVY
Published: September 2011

Protected area management in developing countries faces the challenges of building support for conservation among neighbouring residents and monitoring the social and ecological impacts of conservation programming. This study examined a collaborative resource management (CRM) programme at Kibale National Park (Uganda) that permits residents to fish inside the Park. Like other integrated conservation and development programmes, the goals are to help alleviate poverty and encourage support for conservation and conservation-related behaviours. The programme's impact was empirically analysed using an 81 item personal survey, with 94 CRM fishers and 91 comparison group respondents, and additional data from semi-structured interviews and document review. Fishers’ annual income was significantly greater (median = US$ 376.02 yr−1) than that of the comparison group (median = US$ 196.19 yr−1;p< 0.001), and their tribal affiliation influenced earnings. Fishers indicated greater support for conservation (p< 0.01) than the comparison group. Although some CRM fishers deterred illegal activity, some may extract resources illegally. This study demonstrates that CRM is a viable tool for promoting support for conservation and increasing income, although monitoring of programme participants is needed to deter illegal behaviours and sustain the resource base.
An exploration of spatial patterns of seasonal diarrhoeal morbidity in Thailand
Authors: McCORMICK B. J. J. , ALONSO W. J. , MILLER M. A.
Published: September 2011

Studies of temporal and spatial patterns of diarrhoeal disease can suggest putative aetiological agents and environmental or socioeconomic drivers. Here, the seasonal patterns of monthly acute diarrhoeal morbidity in Thailand, where diarrhoeal morbidity is increasing, are explored. Climatic data (2003–2006) and Thai Ministry of Health annual reports (2003–2009) were used to construct a spatially weighted panel regression model. Seasonal patterns of diarrhoeal disease were generally bimodal with aetiological agents peaking at different times of the year. There is a strong association between daily mean temperature and precipitation and the incidence of hospitalization due to acute diarrhoea in Thailand leading to a distinct spatial pattern in the seasonal pattern of diarrhoea. Model performance varied across the country in relation toper capitaGDP and population density. While climatic factors are likely to drive the general pattern of diarrhoeal disease in Thailand, the seasonality of diarrhoeal disease is dampened in affluent urban populations.
Determination of the burden of hepatitis C virus infection in Ireland
Authors: THORNTON L. , MURPHY N. , JONES L. , CONNELL J. , DOOLEY S. , GAVIN S. , HUNTER K. , BRENNAN A.
Published: September 2011

Information on the burden of hepatitis C virus (HCV) disease is needed to inform policy decisions on primary and secondary prevention. Specimen-based laboratory data (1989–2004) were converted to person-based data and combined with notification data (2004–2009) to describe the burden of HCV infection in Ireland. More than 10 000 people were confirmed as HCV infected in 1989–2004, with the numbers peaking in 2000. The predominant genotypes were 1 (55%) and 3 (39%). Drug use was the most likely risk factor in 80%, with receipt of blood or blood products in 16%. It is estimated that 20 000–50 000 people in Ireland are chronically infected with HCV, a population prevalence of 0·5–1·2%, which is similar to other countries in Northern Europe. This is the first published estimate of the number of chronic HCV infections in Ireland. These data will be of value in health service planning and will contribute to the understanding of HCV infection in Europe.
Studying geodesy and earthquake hazard in and around the New Madrid Seismic Zone
Authors: Boyd Oliver Salz , Magistrale Harold
Published: September 2011

Workshop on New Madrid Geodesy and the Challenges of Understanding Intraplate Earthquakes; Norwood, Massachusetts, 4 March 2011Twenty‐six researchers gathered for a workshop sponsored by the U.S. Geological Survey (USGS) and FM Global to discuss geodesy in and around the New Madrid seismic zone (NMSZ) and its relation to earthquake hazards. The group addressed the challenge of reconciling current geodetic measurements, which show low present‐day surface strain rates, with paleoseismic evidence of recent, relatively frequent, major earthquakes in the region. The workshop presentations and conclusions will be available in a forthcoming USGS open‐file report (http://pubs.usgs.gov).
Estimating contaminant spreading by subsurface water
Authors: Schultz Colin
Published: September 2011

Spills of fuels, solvents, and solid waste continually emit pollutants into groundwater, the major source of drinking water for most of the world. These contaminants can react with dissolved oxygen or other chemicals present in groundwater, leading to natural attenuation. Previous research has shown that in the case of a continuous source of contamination, the most important chemical mixing occurs perpendicular to the direction of groundwater flow. Therefore, estimating transverse mixing in groundwater is important for assessing the danger associated with a contaminant source.
Melting glaciers can change Earth's gravity field
Authors: Kumar Mohi
Published: September 2011

The Earth's rotation causes mass from the ductile mantle to bulge at the equator, making the radius of the Earth about 21 kilometers greater at the equator than at the poles. Over the past 20,000 or so years, the Earth has been becoming more round as it adjusts to the withdrawal of vast continental glaciers after the last ice age: Without the weight of ice pressing down, land has rebounded to give the Earth a more spherical shape. This in turn means that the Earth|'s geoid—the average gravity field across the globe—also became more round. However, in the early 1990s, scientists began to notice that postglacial rebound was starting to become offset by something else, causing the Earth's gravity field to cease changing shape.
Quantifying crustal extension and shortening in the back‐arc region of Northeast Japan
Authors: Okada Shinsuke , Ikeda Yasutaka
Published: September 2011

The Northeast Japan (NEJ) arc has experienced strong extension in the early to middle Miocene time and contractive deformation since Pliocene time. We determine the amounts of the Miocene extension and Pliocene contraction along four transects across the NEJ arc by area‐balancing restoration using seismic reflection, gravity, and surface geologic data. We find that the Miocene extension is as much as 31–56 km while the Pliocene‐Quaternary contraction is only 10–15 km. The style of the Miocene extension in the back‐arc region of NEJ is highly asymmetric; the zone of concentrated extension is characterized by a breakaway fault on the west, a rollover basement anticline on the east, and abnormally deep (∼10 km) basins and strongly rotated fault blocks in between, suggesting the existence of a large‐scale detachment fault at a mid‐crustal level beneath the extended zone. We reveal that the Pliocene‐Quaternary contractive surface deformation in the back‐arc region of NEJ resulted principally from positive tectonic inversion of the underlying detachment fault. Previous works have suggested that Andean‐type orogens have often experienced negative and positive inversions alternately in their back‐arc regions. Although the former has been well documented, for example, for the Cenozoic North American Cordillera, the latter has rarely been reported because subsequent contraction has obscured the older structures. Since the NEJ arc is still at an incipient stage and hence its older structures are well preserved, our study provides an important example of positive tectonic inversion of Andean‐type orogens.
Coarse-graining Brownian motion: From particles to a discrete diffusion equation
Authors: de la Torre J. A. , Español Pep
Published: September 2011

We study the process of coarse-graining in a simple model of diffusion of Brownian particles. At a detailed level of description, the system is governed by a Brownian dynamics of non-interacting particles. The coarse-level is described by discrete concentration variables defined in terms of Delaunay cells. These coarse variables obey a stochastic differential equation that can be understood as a discrete version of a diffusion equation. We study different models for the two basic building blocks of this equation which are the free energy function and the diffusion matrix. The free energy function is shown to be non-additive due to the overlapping of cells in the Delaunay construction. The diffusion matrix is state dependent in principle, but for near-equilibrium situations it is shown that it may be safely evaluated at the equilibrium value of the concentration field.
Depth profile study of Ti implanted Si at very high doses
Authors: Olea J. , Pastor D. , Toledano-Luque M. , Mártil I. , González-Díaz G.
Published: September 2011

A detailed study on the resulting impurity profile in Si samples implanted with high doses of Ti and subsequently annealed by pulsed-laser melting (PLM) is reported. Two different effects are shown to rule the impurity profile redistribution during the annealing. During the melting stage, the thickness of the implanted layer increases while the maximum peak concentration decreases (box-shaped effect). On the contrary, during the solidifying stage, the thickness of the layer decreases and the maximum peak concentration increases (snow-plow effect). Both effects are more pronounced as the energy density of the annealing increases. Moreover, as a direct consequence of the snow-plow effect, part of the impurities is expelled from the sample through the surface.
Nonlinear low frequency wave propagation in electronegative dusty plasma: Effects of adiabatic and nonadiabatic charge variations
Authors: Sarkar Subrata , Ghosh Samiran , Khan Manoranjan , Gupta M. R.
Published: September 2011

The effects of both adiabatic and nonadiabatic charge variations on small but finite amplitude nonlinear dust acoustic wave (DAW) have been investigated in an electronegative dusty plasma in presence of a static magnetic field. It is found that in case of adiabatic charge variations, the nonlinear wave is governed by the Zakharov-Kuznetsov (ZK) equation which yields the usual solitary wave solution. On the other hand, in case of nonadiabatic charge variations, the dynamics is governed by the Zakharov-Kuznetsov-Burgers’ (ZKB) equation which exhibits shock like structures. The results are discussed in the context of cometary plasma.
Efficiency of magnetic plane wave pumping of a ferrofluid through a planar duct
Authors: Felderhof B. U.
Published: September 2011

The efficiency of ferrohydrodynamic pumping of a ferrofluid through a planar duct by means of a running magnetic plane wave is studied to second order in the amplitude of the exciting current density. The rate of dissipation in the fluid is calculated from the first order magnetic field and magnetization. It turns out that the efficiency, defined as the ratio of net flow velocity to power input, is comparable in magnitude to that for Stokes peristaltic pumping. The theory for electrohydrodynamic pumping of a polar liquid by means of a running electric plane wave is shown to be nearly identical.
Resonant two-photon ionization spectroscopy of jet-cooled OsN: 520–418 nm
Authors: Garcia Maria A. , Morse Michael D.
Published: September 2011

The optical transitions of supersonically cooled OsN have been investigated in the range from 19 200 to 23 900 cm−1 using resonant two-photon ionization spectroscopy. More than 20 vibronic bands were observed, 17 of which were rotationally resolved and analyzed. The ground state is confirmed to be 2Δ5/2, deriving from the 1σ2 2σ2 1π4 1δ3 3σ2 electronic configuration. The X 2Δ5/2 ground state rotational constant for 192Os14N was found to be B0 = 0.491921(34) cm−1, giving r0 = 1.62042(6) Å (1σ error limits). The observed bands were grouped into three band systems with Ω′ = 7/2 and four with Ω′ = 3/2, corresponding to the three 2Φ7/2 and four 2Π3/2 states expected from the 1σ2 2σ2 1π4 1δ3 3σ1 2π1 and 1σ2 2σ2 1π4 1δ2 3σ2 2π1 electronic configurations. In addition, two interacting upper states with Ω′ = 5/2 were observed, one of which is thought to correspond to a 1σ2 2σ2 1π3 1δ3 3σ2 2π1, 2Δ5/2 state. Spectroscopic constants are reported for all of the observed states, and comparisons to related molecules are made. The ionization energy of OsN is estimated as IE(OsN) = 8.80 ± 0.06 eV.
Wideband ultraflat slow light with large group index in a W1 photonic crystal waveguide
Authors: Liang Jian , Ren Li-Yong , Yun Mao-Jin , Han Xu , Wang Xing-Jun
Published: September 2011

We demonstrate that slow light with large group-index, wideband, and low dispersion can be realized in a silicon-on-insulator W1-type photonic crystal waveguide by simply shifting the first two rows of air-holes adjacent to the waveguide to specific directions. Keeping the group index at 46, 60, 86, 111, 151, and 233, respectively, while restricting its variation within a ± 10% range, we accordingly obtain a slow light bandwidth of 9.0 nm, 6.7 nm, 4.6 nm, 3.3 nm, 2.4 nm, and 1.7 nm, respectively. The normalized delay-bandwidth product keeps around 0.25 for all cases. Moreover, we obtain ultraflat slow light with bandwidths over 3.0 nm, 2.4 nm, 1.6 nm, 1.3 nm, 0.93 nm, and 0.6 nm, respectively, where the group index variation is in a range of only ± 0.8%. Numerical simulations are performed, utilizing the 2D plane wave expansion method and the finite-difference time-domain method.
Oxygen vacancy mediated large magnetization in chemically synthesized Ni-doped HfO2 nanoparticle powder samples
Authors: Kumar Sharma Manoj , Kumar Mishra Dilip , Ghosh Sabyasachi , Kanjilal Dinakar , Srivastava Pankaj , Chatterjee Ratnamala
Published: September 2011

A cost-effective solution based chemical method of synthesizing nanostructured Hf1−xNixO2 with 0 ≤ x ≤ 0.05 in powder form, from easily available laboratory reagents is presented. Production of uniformly shaped and sized (13–16 nm) nanoparticles with excellent crystallinity is demonstrated by transmission electron microscopy, x-ray diffraction (XRD) studies and Raman spectra. The origin of ferromagnetism in the Ni-doped HfO2 nanoparticle powder samples is investigated. Magnetization studies along with x-ray photoelectron spectroscopy (XPS) studies suggest that some of the Ni-ions are substitutionally incorporated in HfO2 host matrix. The XPS studies also show the presence of a small fraction of Ni metal (most likely Ni nanoclusters), undetected in standard XRD for lightly doped samples, suggesting that the observed room temperature ferromagnetism is at least partly due to Ni nanoclusters. The observed large value (∼6 emu/g) of magnetization, may not be entirely due to the presence of Ni metal cluster, can be understood in terms of oxygen vacancies created to retain charge neutrality of HfO2 matrix as some Ni ions replace Hf4+, resulting in ferromagnetic interactions at lower concentrations.
Sulfur-impurity induced amorphization of nickel
Authors: Yuan Zaoshi , Chen Hsiu-Pin , Wang Weiqiang , Nomura Ken-ichi , Kalia Rajiv K. , Nakano Aiichiro , Vashishta Priya
Published: September 2011

Recent experimental and theoretical studies have shown an essential role of sulfur segregation-induced amorphization of crystalline nickel leading to its embrittlement at a critical sulfur concentration of ∼14%, but the atomistic mechanism of the amorphization remains unexplained. Here, molecular dynamics simulations reveal that the large steric size of sulfur impurity causes strong sulfur-sulfur interaction mediated by lattice distortion up to the next nearest-neighbor lattice sites and that amorphization occurs at the percolation threshold of the sulfur-sulfur network with the next nearest-neighbor connectivity. Furthermore, the generality of the amorphization mechanism due to the percolation of an impurity network is confirmed for a model binary material.
Internal heating driven convection at infinite Prandtl number
Authors: Whitehead Jared P. , Doering Charles R.
Published: September 2011

We derive an improved rigorous lower bound on the space and time averaged temperature ⟨T⟩ of an infinite Prandtl number Boussinesq fluid contained between isothermal no-slip boundaries driven by uniform internal heating. A singular stable stratification is introduced as a perturbation to a non-singular background profile yielding ⟨T⟩ ⩾ 0.419[R log R]−1/4 where R is the heat Rayleigh number. The analysis relies on a generalized Hardy-Rellich inequality that is proved in the Appendix.
Optical spectroscopy of Yb3+ centers in BaMgF4 ferroelectric crystal
Authors: García-Santizo J. V. , del Rosal B. , Ramírez M. O , Bausá L. E. , Víllora E. G. , Molina P. , Vasyliev V. , Shimamura K.
Published: September 2011

We report on the optical characterization of Yb3+ doped BaMgF4 nonlinear fluoride crystal grown by the Czochralski technique. Low temperature absorption spectroscopy reveals that Yb3+ incorporates into the matrix at four well differentiated centers. High resolution site selective experiments have been performed to determine the energy level schemes associated with the major Yb3+ centers detected in the system. The fluorescence decay times recorded at 10 K under selective excitation are analyzed for each Yb3+ center. The spectroscopic behavior of the codoped Yb3+:Na+:BaMgF4 system has been also investigated. Codoping with Na+ eliminates two Yb3+ centers present in the singly doped Yb3+:BaMgF4 crystal. The charge compensation mechanisms and site location for Yb3+ in the fluoride matrix are discussed.
A wide-angle polarization-insensitive ultra-thin metamaterial absorber with three resonant modes
Authors: Li Long , Yang Yang , Liang Changhong
Published: September 2011

In this paper, we report the design, fabrication, and measurement of a metamaterial absorber that is constructed of a periodic array of tetra-arrow resonators (TARs) printed on a dielectric material backed by a metal ground. The TAR absorber can operate at three different resonant modes. By adjusting geometry parameters of the structure, we can obtain a dual-band, polarization-insensitive, wide-angle thin absorber or a single band but ultra-miniature absorber that corresponds to three different resonant modes. Waveguide experiments are conducted to verify the proposed designs effectively. The measurement results show that all three absorptivity peaks come near to perfection.
Electrostrictive fluid pressure from a laser beam
Authors: Ellingsen Simen Å. , Brevik Iver
Published: September 2011

Recent times have seen a surge of research activity on systems combining fluid mechanics and electromagnetic fields. In radiation optics, whenever information about the distribution of pressure in a dielectric fluid is required, the contribution from electrostriction becomes important. In the present paper, we calculate how the local pressure varies with position and time when a laser beam is imposed in a uniform fluid. A Gaussian intensity profile of arbitrary time dependence is assumed for the beam, and general results are derived in this case. For demonstration, we analyze two different cases: first, that the beam is imposed suddenly (mathematically in the form of a step function) and second, that the beam is switched on in a soft way. In both cases, simple analytical expressions for the pressure distribution are found.
The use of the Health of the Nation Outcome Scales (HoNOS) to inform discharge and transfer decisions in community mental health services
Authors: Prowse Liz , Coombs Tim
Published: September 2011

Discharge from public community mental health
services has proven difficult for mental health
workers and managers. Mental illness can often
be long term, with ongoing disability, requiring a
need for corresponding long-term care. Community
mental health services are now becoming
recovery focused and are recognising the need for
alternative management arrangements for individuals
with long-term care needs. There are, however
few tools to assist in the decision making
about discharge or transfer of care between community
mental health teams. This article describes
a quality improvement project to develop a flag for
mental health workers to prompt decisions regarding
discharge and transfer using the Health of the
Nation Outcome Scales (HoNOS). Relevant literature
and HoNOS data collected as part of routine
clinical practice were reviewed to develop the flag.
The implementation process is described along
with plans for future developments.
Local trends in emergency department attendances by older patients in an ageing national population
Authors: Chu Kevin , Brown Anthony , Lukin William
Published: September 2011

Nursing-led aged care services were set up at our
Emergency Department (ED) in 2004?05 to assist
in the appropriate discharge of older patients. This
study examined local trends in ED attendances by
older patients. A retrospective study was conducted
at an inner-city adult ED in a region with a
2.2% annual growth rate. Patient demographics,
Australasian Triage Scale (ATS) category and
admission/discharge status were collected from
January 2002 to December 2006. Total ED attendances
increased 7.7% from 66 687 in 2002 to
71 801 in 2006. Older patients? attendances, however,
decreased 3.1% from 12 356 to 11 971. This
decrease in ED attendances by older patients was
unexpected. This may represent local population
trends and/or be related to ED services designed
to manage older patients and nursing home residents
in the community. The planning of health
services for older people therefore needs to take
into consideration the influences on local trends in
changing population demographics.
The effect of guidance in the use of routine outcome measures in clinical meetings
Authors: Trauer Tom , Pedwell Glenda , Gill Lisa
Published: September 2011

Routine outcome measures (ROM) have now
been introduced into all Australian public mental
health services, but experience suggests that
many clinical staff lack expertise in using them. In
2005 under the Quality Through Outcomes Network
(QUATRO), the Victorian Department of
Human Services set up three teams aimed at
consolidating the use of ROM and furthering
sustainability through a variety of peer-support
activities. We report on an initiative undertaken by
one of these teams. QUATRO team members
attended team meetings of four adult community
teams (three metropolitan and one rural) fortnightly
over about 3 months. QUATRO staff contributed
to discussion of outcome measures
during routine clinical review, using local and
national outcome measurement data and tools,
and their own expertise. Attitudes of clinicians
toward ROM in general and the specific instruments
were assessed at the beginning and end of
the period, and again after about 5 months.
Qualitative findings consist of observations of
factors that assist and hinder use of ROM. The
initiative identified steps that staff can take to
make ROM more useful in their work.
The Man Who Would Not Be King: Abu'l-Fath Sultan Muhammad Mirza Safavi in India
Authors: Rota Giorgio
Published: September 2011

The fall of Isfahan to the afghans in 1722 marked the end of effective Safavid rule over Iran, but not the disappearance of the Safavids from Persia's political scene. During the entire course of the eighteenth century, many pretenders to the Persian throne made their bids for power by trying to capitalize on their claims to Safavid origins, genuine in some cases, spurious in others. A few of them played a part in the struggle against the Afghans (for instance, Shah Tahmasp II and Mirza Sayyid Ahmad), and others managed to ascend a throne, although only as mere figureheads (like Shah ᶜAbbas III, Shah Sulayman II, and Shah Ismaᶜil III). Since the issue has already been dealt with by John R. Perry in a very detailed article, I need not elaborate further. Perry, however, devoted only a few lines to the very last of them, Abu'l-Fath Mirza b. Shah Sultan Husayn II b. Shah Tahmasp II, also known as Sultan Muhammad II, whose claims Perry dismissed as certainly spurious.
What is so special about Reading Recovery?
Authors: Hurry Jane
Published: September 2011

Reading Recovery is a highly successful and widely used intervention for children with reading difficulties. However, it is an intensive intervention and some have argued that it is for this reason alone that it is effective. This argument is examined but found to be unsound. The central features of Reading Recovery are then described under the headings of assessment, curriculum and instruction, and the empirical evidence of their value reviewed. Using this method to analyse Reading Recovery as a case‐study of successful intervention certain key elements are revealed. The intensity of the intervention is identified as a necessary but not sufficient ingredient for effective remediation. Other factors of importance are the rigour and focus of assessment, the breadth of the curriculum which includes writing as well as reading, and the quality of instruction.
The mediating role of LEAs in the interpretation of government assessment policy at school level in England
Authors: Conner Colin , James Mary
Published: September 2011

The authors of this paper have conducted research into the implementation of National Curriculum assessment at Key Stage 1 by local education authorities in one particular region of the United Kingdom, East Anglia. They found that policy documents were being interpreted in a number of different ways, thus allowing a variety of practices to develop. This has allowed policy implementation to be shaped to meet local needs, in particular with regard to audit or moderation at this key stage.
Models of teacher assessment among primary school teachers in England
Authors: Gipps Caroline , McCallum Bet , Brown Margaret
Published: September 2011

Building on their study of assessment practices at Key Stage 1, the authors use similar methods to examine practices at Key Stage 2. They identify teacher styles, ranging from Testers to Diagnostic Trackers, and look at the way those teachers carried out assessments, gathered evidence, made decisions about National Curriculum levels and recorded their findings. Finally, they make comparisons between practices concerning assessment at the two'Key Stages.
Assessment in French primary schools
Authors: Broadfoot Patricia , Osborn Marilyn , Panel Claire , Pollard Andrew
Published: September 2011

Despite its current high regard in parts of the English educational community, education in France has been as much the subject of public and political concern in recent years as it has in many other countries. One manifestation of this concern was the Loi Jospin of 1989, the aim of which was to continue to encourage the growth of diversity among schools as a response to local needs. Associated with this goal was that of making teachers more willing and able to respond to the increasingly diverse needs of their pupils. By so doing, it was hoped to raise the overall level of student success within the system. This paper looks at one aspect of teachers’ practice and the impact of current reforms on it–that of assessment. Having briefly described the provisions of the Jospin Law, it discusses how these are affecting teachers’ attitudes and practice, using data from the ESRC‐funded ‘Systems, Teachers and Educational Policy’ (STEP) project (ESRC Award No.: R 000 23 4673). Some tentative conclusions about the scale of change and the significance of French primary teachers’ attitudes to assessment are offered.
An analysis of the rationales for learning history given by children and teachers at Key Stage 2
Authors: Huggins Mike
Published: September 2011

Subject knowledge at Key Stage 2 of the English National Curriculum has recently assumed increased importance, leading, to an increased research interest in the forms of subject content knowledge and pedagogic content knowledge employed by teachers. This paper examines the extent to which teachers and pupils were aware of a specific subject curriculum rationale. The paper discusses the findings of an enquiry into the extent to which non‐specialist teachers (n = 40), initial teacher training students (n = 46) and Key Stage 2 pupils in four primary schools exhibited an understanding of the reasons why history should be studied, following the introduction of the National Curriculum for history in 1991. Results showed that experienced teachers had a tacit understanding of the aims of history produced by the National Curriculum Council, although students’ understandings were less well developed. Teachers had succeeded in transmitting some key ideas about why history should be studied to their pupils, although differences between schools show that teaching makes a difference. However, some pupils had only sketchy ideas about why they studied the subject or did not find it exciting or enjoyable.
Recent developments in the science education of 14‐16 year olds in Northern Ireland or ’A Tale of Two Policies’
Authors: Jarman Ruth , McAleese Liam
Published: September 2011

In Northern Ireland, in recent years, concerns have been expressed about the large number of pupils who do not continue with formal science education beyond the age of 14. The introduction of a statutory curriculum, however, brought with it the requirement that all our young people should study science throughout compulsory schooling. This paper describes the implementation of this policy as it applies to 14‐16 year olds, including the development of the science programmes, their selection by schools and their uptake by pupils. The marked difference between the outcome of the new curriculum policy in the province and the outcome of a similar science policy in England is explored in terms of the distinctive features of the education system in Northern Ireland.
The paradoxical position of careers teachers in relation to the Training Credits initiative as an innovation
Authors: Sparkes Andrew , Hodkinson Phil
Published: September 2011

Within schools the history of careers teaching has been characterized by its margin‐alization in the educational process. Drawing upon interview data this paper explores how careers teachers experience various forms of marginality within a recent vocational initiative involving Training Credits (TCs).1 It is suggested that their involvement in this initiative has acted to exacerbate the uncertainties and ambiguities that many careers teachers experience regarding their role and status within schools. Finally, the problems raised by their continued marginalization for the success or otherwise of TCs as an innovation are considered.