bluuebunny/crossref_metadata_2025 huggingface dataset:
Snag distributions in relation to human access in ponderosa pine forests
Authors: Hollenbeck Jeff P. , Bate Lisa J. , Saab Victoria A. , Lehmkuhl John F.
Published: March 2013

Ponderosa pine (Pinus ponderosa) forests in western North America provide habitat for numerous cavity‐using wildlife species that often select large‐diameter snags for nesting and roosting. Yet large snags are often removed for their commercial and firewood values. Consequently we evaluated effects of human access on snag densities and diameter‐class distributions at nine locations in ponderosa pine forests throughout the interior western United States. We found no relationship between small‐diameter (23–50 cm diam breast ht [dbh]) snags and human access measures (i.e., road density, distance to nearest town, and topography). However, large‐snag (≥50 cm dbh) density was best predicted by road density, which suggested a decline, on average, of 0.7 large snags/ha for every km of road/km2. Most locations had relatively high densities of small‐diameter snags (<23 cm dbh) and diminishing density as diameter class increased. Idaho and Colorado study locations had higher snag densities in the largest diameter classes compared with remaining locations. These locations experienced minimal commercial timber harvest, were situated far from towns, and had few or no roads. Persistence of large‐diameter snags and adequate snag densities for wildlife requires consideration of human access characteristics at coarse spatial scales. Snag management guidelines may need to incorporate these measures and focus more on retention of large‐diameter snags than minimum density targets. © 2013 The Wildlife Society.
Surgical Resection Versus Conformal Radiotherapy Combined With TACE for Resectable Hepatocellular Carcinoma With Portal Vein Tumor Thrombus: A Comparative Study
Authors: Tang Qing‐he , Li Ai‐jun , Yang Guang‐ming , Lai Eric C.H. , Zhou Wei‐ping , Jiang Zhi‐hao , Lau Wan Yee , Wu Meng‐chao
Published: March 2013

Background

The aim of this study was to compare the results of surgical resection with three‐dimensional conformal radiotherapy (3D‐CRT) in the treatment of resectable hepatocellular carcinoma (HCC) with portal vein tumor thrombus (PVTT). Transarterial chemoembolization (TACE) was given to both groups of patients when possible.

Methods

A retrospective study of 371 patients with resectable HCC with PVTT was conducted in two tertiary referral centers. The treatment of choice for these patients in one center was surgical resection. In the other center it was 3D‐CRT. In the radiotherapy group (RG, n = 185), patients received 3D‐CRT to the tumor and PVTT for a total radiation dose of 30–52 Gy (median 40 Gy). In the surgical group (SG, n = 186), patients underwent surgical resection. TACE was applied after surgery or 3D‐CRT and then was repeated every 4–6 weeks if the patient tolerated the treatment.

Results

The median survival was 12.3 months for RG and 10.0 months for SG. The 1‐, 2‐, and 3‐year overall survivals were 51.6, 28.4, and 19.9 %, respectively, for RG and 40.1, 17.0, and 13.6 %, respectively, for SG (p = 0.029). Stepwise multivariate analysis showed that the extent of PVTT and mode of treatment were independent risk factors of overall survival. The most common cause of death after treatment was liver failure as a consequence of progressive intrahepatic disease.

Conclusions

3D‐CRT gave better survival than surgical resection for HCC with PVTT.
Investigation of sub-Kolmogorov inertial particle pair dynamics in turbulence using novel satellite particle simulations
Authors: Ray Baidurja , Collins Lance R.
Published: March 2013

Clustering (or preferential concentration) of weakly inertial particles suspended in a homogeneous isotropic turbulent flow is driven primarily by the smallest eddies at the so-called Kolmogorov scale. In particle-laden large-eddy simulations (LES), these small scales are not resolved by the grid and hence their effect on both the resolved flow scales and the particle motion have to be modelled. In order to predict clustering in a particle-laden LES, it is crucial that the subgrid model for the particles captures the mechanism by which the subgrid scales affect the particle motion (Ray & Collins, J. Fluid Mech., vol. 680, 2011, pp. 488–510). In this paper, we describe novel satellite particle simulations (SPS), in which we study the clustering and relative velocity statistics of inertial particles at separation distances well below the Kolmogorov length scale. SPS is designed to isolate pairwise interactions of particles, and is therefore well suited for developing two-particle models. We show that the power-law dependence of the radial distribution function (RDF), a statistical measure of clustering, is predicted by the SPS in excellent agreement with direct numerical simulations (DNS) for Stokes numbers up to 3, implying that no explicit information from the inertial range is required to accurately describe particle clustering. This result further explains our successful prediction of the RDF power using the drift-diffusion model of Chun et al. (J. Fluid Mech., vol. 536, 2005, pp. 219–251) for $\mathit{St}\leq 0. 4$. We also consider the second-order longitudinal relative velocity structure function for the particles; we show that the SPS is able to capture its power-law exponent for $\mathit{St}\leq 0. 5$ and attribute the disagreement at larger $\mathit{St}$ to the effect of the larger scales of motion not captured by the SPS. Further, the SPS is able to capture the ‘caustic activation’ of the structure function at zero separation and predict the critical $\mathit{St}$ and rate of activation in agreement with the DNS (Salazar & Collins, J. Fluid. Mech., vol. 696, 2012, pp. 45–66). We show comparisons between filtered DNS and equivalently filtered SPS, and the findings are similar to the unfiltered case. Overall, SPS is an efficient and accurate computational tool for investigating particle pair dynamics at small separations, as well as an interesting platform for developing LES subgrid models designed to accurately reproduce particle clustering.
The non-resonant response of fluid in a rapidly rotating sphere undergoing longitudinal libration
Authors: Zhang Keke , Chan Kit H. , Liao Xinhao , Aurnou Jonathan M.
Published: March 2013

We investigate the problem of oscillatory flow of a homogeneous fluid with viscosity $\nu $ in a fluid-filled sphere of radius $a$ that rotates rapidly about a fixed axis with angular velocity ${\Omega }_{0} $ and that undergoes weak longitudinal libration with amplitude $\epsilon {\Omega }_{0} $ and frequency $\hat {\omega } {\Omega }_{0} $, where $\epsilon $ is the Poincaré number with $\epsilon \ll 1$ and $\hat {\omega } $ is dimensionless frequency with $0\lt \hat {\omega } \lt 2$. Three different methods are employed in this investigation: (i) asymptotic analysis at small Ekman numbers $E$ defined as $E= \nu / ({a}^{2} {\Omega }_{0} )$; (ii) linear numerical analysis using a spectral method; and (iii) nonlinear direct numerical simulation using a finite-element method. A satisfactory agreement among the three different sets of solutions is achieved when $E\leq 1{0}^{- 4} $. It is shown that the flow amplitude $\vert \boldsymbol{u}\vert $ is nearly independent of both the Ekman number $E$ and the libration frequency $\hat {\omega } $, always obeying the asymptotic scaling $\vert \boldsymbol{u}\vert = O(\epsilon )$ even though various spherical inertial modes are excited by longitudinal libration at different libration frequencies $\hat {\omega } $. Consequently, resonances do not occur in this system even when $\hat {\omega } $ is at the characteristic value of an inertial mode. It is also shown that the pressure difference along the axis of rotation is anomalous: this quantity reaches a sharp peak when $\hat {\omega } $ approaches a characteristic value. In contrast, the pressure difference measured at other places in the sphere, such as in the equatorial plane, and the volume-integrated kinetic energy are nearly independent of both the Ekman number $E$ and the libration frequency $\hat {\omega } $. Absence of resonances in a fluid-filled sphere forced by longitudinal libration is explained through the special properties of the analytical solution that satisfies the no-slip boundary condition and is valid for $E\ll 1$ and $\epsilon \ll 1$.
Gravity-driven granular free-surface flow around a circular cylinder
Authors: Cui X. , Gray J. M. N. T.
Published: March 2013

Snow avalanches and other hazardous geophysical granular flows, such as debris flows, lahars and pyroclastic flows, often impact on obstacles as they flow down a slope, generating rapid changes in the flow height and velocity in their vicinity. It is important to understand how a granular material flows around such obstacles to improve the design of deflecting and catching dams, and to correctly interpret field observations. In this paper small-scale experiments and numerical simulations are used to investigate the supercritical gravity-driven free-surface flow of a granular avalanche around a circular cylinder. Our experiments show that a very sharp bow shock wave and a stagnation point are generated in front of the cylinder. The shock standoff distance is accurately reproduced by shock-capturing numerical simulations and is approximately equal to the reciprocal of the Froude number, consistent with previous approximate results for shallow-water flows. As the grains move around the cylinder the flow expands and the pressure gradients rapidly accelerate the particles up to supercritical speeds again. The internal pressure is not strong enough to immediately push the grains into the space behind the cylinder and instead a grain-free region, or granular vacuum, forms on the lee side. For moderate upstream Froude numbers and slope inclinations, the granular vacuum closes up rapidly to form a triangular region, but on steeper slopes both experiments and numerical simulations show that the pinch-off distance moves far downstream.
Exact solutions for cylindrical ‘slip–stick’ Janus swimmers in Stokes flow
Authors: Crowdy Darren G.
Published: March 2013

A Janus swimmer is any force-free, torque-free organism, particle or micro-robot operating at low Reynolds numbers and having contiguous regions of its boundary on which different boundary conditions are in play. In this paper we study a ‘slip–stick’ Janus swimmer theoretically within a two-dimensional model. The boundary of the swimmer is split into two zones: its motion is driven by an imposed tangential stress on a portion of the boundary with the complement taken to be a no-slip surface. The Stokes flow generated by the swimmer, and its swimming speed, are determined in closed analytical form as a function of the angle over which the stress actuation is active.
ELUSIVE CODES IN HAMMING GRAPHS
Authors: HAWTIN DANIEL R. , GILLESPIE NEIL I. , PRAEGER CHERYL E.
Published: March 2013

We consider a code to be a subset of the vertex set of a Hamming graph. We examine elusive pairs, code-group pairs where the code is not determined by knowledge of its set of neighbours. We construct a new infinite family of elusive pairs, where the group in question acts transitively on the set of neighbours of the code. In these examples, the alphabet size always divides the length of the code. We show that there is no elusive pair for the smallest set of parameters that does not satisfy this condition. We also pose several questions regarding elusive pairs.
Local Bondage in Global Economies: Servants, wage earners, and indentured migrants in nineteenth-century France, Great Britain, and the Mascarene Islands
Authors: STANZIANI ALESSANDRO
Published: March 2013

This paper compares the definitions, practices, and legal constraints on labour in Britain, France, Mauritius, and Reunion Island in the eighteenth and nineteenth centuries. It argues that the way in which indentured labour was defined and practised in the colonies was linked to the definition and practice of wage labour in Europe and that their development was interconnected. The types of bondage that existed in the colonies were extreme forms of the notion, practices, and rules of labour in Europe. It would have been impossible to develop the indenture contract in the British and French empires if wage earners in Britain and France had not been servants. The conceptions and practices of labour in Europe and its main colonies influenced each other and were part of a global dynamic.
Cognitive biases and auditory verbal hallucinations in healthy and clinical individuals
Authors: Daalman K. , Sommer I. E. C. , Derks E. M. , Peters E. R.
Published: March 2013

Background

Several cognitive biases are related to psychotic symptoms, including auditory verbal hallucinations (AVH). It remains unclear whether these biases differ in voice-hearers with and without a ‘need-for-care’.

Method

A total of 72 healthy controls, 72 healthy voice-hearers and 72 clinical voice-hearers were compared on the Cognitive Biases Questionnaire for psychosis (CBQp), which assesses ‘intentionalizing’, ‘jumping to conclusions’, ‘catastrophizing’, ‘dichotomous thinking’ and ‘emotional reasoning’ in vignettes characterized by two themes, ‘threatening events’ and ‘anomalous perceptions’.

Results

Healthy voice-hearers scored intermediately on total CBQp between the control and clinical groups, differing significantly from both. However, on four out of five biases the scores of the healthy voice-hearers were comparable with those of the healthy controls. The only exception was ‘emotional reasoning’, on which their scores were comparable with the clinical group. Healthy voice-hearers demonstrated fewer biases than the psychotic patients on the ‘threatening events’, but not the ‘anomalous perceptions’, vignettes. CBQp scores were related to both cognitive and emotional, but not physical, characteristics of voices.

Conclusions

Most cognitive biases prevalent in clinical voice-hearers, particularly with threatening events themes, are absent in healthy voice-hearers, apart from emotional reasoning which may be specifically related to the vulnerability to develop AVH. The association between biases and both beliefs about voices and distress/emotional valence is consistent with the close links between emotions and psychotic phenomena identified by cognitive models of psychosis. The absence of reasoning biases might prevent the formation of threatening appraisals about anomalous experiences, thereby reducing the likelihood of distress and ‘need for care’.
Interference and multipath mitigation utilising a two‐stage beamformer for global navigation satellite systems applications
Authors: Daneshmand Saeed , Broumandan Ali , Nielsen John , Lachapelle Gérard
Published: March 2013

The performance of location‐based services provided by global navigation satellite systems is compromised by interference and multipath propagations. Although time/frequency interference suppression methods have been widely studied in the literature, they fail to cope with wideband interference signals. Instead, techniques utilising several antenna elements can be employed to mitigate both narrowband and broadband interference signals. However, the performance of beamforming techniques utilising antenna arrays severely degrades in dealing with correlated and coherent multipath components which cause signal cancellation phenomenon and temporal correlation matrix rank deficiency. This study proposes a two‐stage beamformer to jointly deal with interference and multipath signals. In the first stage, before the despreading process, by applying the subspace method, the interference subspace is estimated and used as a constraint for the optimisation problem in the next stage. In the second stage, a modified version of the minimum power distortionless response beamformer employing several overlapping sub‐arrays called the minimum difference output power method is utilised to mitigate the correlated multipath components. The proposed beamformer can deal with the signal cancellation phenomenon and temporal correlation matrix rank deficiency. Several simulation examples and a real data test are provided to illustrate the effectiveness of the proposed beamformer. Results show that the proposed method is able to put deep nulls in the direction of the narrowband and wideband interference signals, and significantly reduces the multipath‐induced time of the arrival error.
Improved detection probability of a radar target in the presence of multipath with prior knowledge of the environment
Authors: Hayvaci Harun Taha , De Maio Antonio , Erricolo Danilo
Published: March 2013

A new method to address radar target detection problems in multipath environments is considered. The novelty of the proposed method is that it exploits prior knowledge on the environment and combines it with ray‐tracing electromagnetic modelling to determine some information about the possible multipath structure. This information is used to separate the environment into different regions based upon the behaviour of the multipath components. Specifically, as a case study, the authors consider a radar and a target in the presence of a perfectly reflecting planar surface. For this environment, three regions are determined based on the amount of overlap among the multipath components. For each region, receivers are designed exploiting the multipath structure. Thus, a different viewpoint to analyse radar detection problems is suggested. The two main results are the improvement in the target probability of detection, by properly accounting for the multipath and a priori determination of the best performing detector based upon the location of the target and the available signal‐to‐noise ratio.
Oceanic Corpo-Graphies, Refugee Bodies and the Making and Unmaking of Waters
Authors: Perera Suvendrini
Published: March 2013

This essay considers the challenges that the gendered and raced transnational subaltern refugee subject poses to the order of ‘the liberal state’ and ‘the liberal subject’, and argues that the latter are bound up in complex ways with entrenched understandings of the ocean as elementally distinct from land. This distinction, constituted by the freedom of the sea-going individualist liberal subject, invariably raced as white and gendered as male, to range across the waves in search of new worlds to conquer, is one that is continually reproduced both in popular culture's contemporary sea romances, and in the spatial and legal demarcations of the nation and its limits. In the diverse forms of traffic flowing from south to north, the historical oceanic mobility of this unfettered liberal subject (always shadowed and weighted down by its invisible freight of non-white bodies) now meets the transversal movements of the contemporary transnational subaltern as complex subject. Through the narratives of two refugees to Australia, the article traces the possibilities of an embodied refugee poetics for inscribing new geographies across the global borderlands.
Narcissus: Woman, Water and the West
Authors: Wick Alexis
Published: March 2013

This essay explores the symbiotic relationship between European modernity, its vision of woman and water. The union of these three metaconcepts is consecrated by the Ovidian story of Narcissus and his other, Echo. The West finally found itself completely through Hegel, the Ur-narcissist, who explains the immutable link between that European monopoly, history (by which he means the potential for becoming modern), and the sea. The narcissism of modernity is the great theme of Marx and Engels in the Communist Manifesto, which shows how the bourgeoisie seeks to remake the entire world in its own image. Psychoanalysis, through the writings of Ferenczi, joined in cementing the connection, likening woman to the primal sea to which the male ever yearns to return. And Foucault suggests a potential conclusion from this metaconceptual constellation: that Man, a Western creation, may well disappear like a face drawn on a sandy beach.
Observation of emission process in hydrogen-like nitrogen Z-pinch discharge with time integrated soft X-ray spectrum pinhole image
Authors: Sakai Y. , Rosenzweig J. , Kumai H. , Nakanishi Y. , Ishizuka Y. , Takahashi S. , Komatsu T. , Xiao Y. , Bin H. , Quishi Z. , Hayashi Y. , Song I. , Kawamura T. , Watanabe M. , Hotta E.
Published: March 2013

The emission spectra of hydrogen-like nitrogen Balmer at the wavelength of 13.4 nm in capillary Z-pinch discharge plasma are experimentally examined. Ionization to fully strip nitrogen at the pinch maximum, and subsequent rapid expansion cooling are required to establish the population inversion between the principal quantum number of n = 2 and n = 3. The ionization and recombination processes with estimated plasma parameters are evaluated by utilizing a time integrated spectrum pinhole image containing radial spatial information. A cylindrical capillary plasma is pinched by a triangular pulsed current with peak amplitude of 50 kA and pulse width of 50 ns.
Dispersion properties of a 2D magnetized plasma metallic photonic crystal
Authors: Fu T. , Yang Z. , Shi Z. , Lan F. , Li D. , Gao X.
Published: March 2013

This is a study on a 2D magnetized plasma-filled metal photonic crystal (PMPC). We analyze the dispersion relation of the magnetized PMPC by using the finite-difference time-domain method. Results show a cutoff frequency for the PMPC, and two flat bands and new forbidden band gaps appear due to the external magnetic field. Adjusting the external magnetic field can control the positions of the flat bands, cutoff frequency, and location and width of the local gap. These results provide theoretical basis for designing tunable photonic crystal devices.
Poisson bialgebras
Authors: Ni Xiang , Bai Chengming
Published: March 2013

We introduce a notion of Poisson bialgebra as an analogue of a Lie bialgebra of Drinfeld. Poisson bialgebras exhibit many familiar properties of Lie bialgebras. In particular, they can be constructed from a combination of the classical Yang-Baxter equation and the associative Yang-Baxter equation and there exists a natural Drinfeld classical double. Moreover, Poisson bialgebras are related to certain algebraic structures and they fit naturally into a framework to construct compatible Poisson brackets in integrable systems.
Derivation of a true (t → 0+) quantum transition-state theory. I. Uniqueness and equivalence to ring-polymer molecular dynamics transition-state-theory
Authors: Hele Timothy J. H. , Althorpe Stuart C.
Published: March 2013

Surprisingly, there exists a quantum flux-side time-correlation function which has a non-zero t → 0+ limit and thus yields a rigorous quantum generalization of classical transition-state theory (TST). In this Part I of two articles, we introduce the new time-correlation function and derive its t → 0+ limit. The new ingredient is a generalized Kubo transform which allows the flux and side dividing surfaces to be the same function of path-integral space. Choosing this function to be a single point gives a t → 0+ limit which is identical to an expression introduced on heuristic grounds by Wigner in 1932; however, this expression does not give positive-definite quantum statistics, causing it to fail while still in the shallow-tunnelling regime. Positive-definite quantum statistics is obtained only if the dividing surface is invariant to imaginary-time translation, in which case the t → 0+ limit is identical to ring-polymer molecular dynamics (RPMD) TST. The RPMD-TST rate is not a strict upper bound to the exact quantum rate, but is a good approximation to one if real-time coherence effects are small. Part II will show that the RPMD-TST rate is equal to the exact quantum rate in the absence of recrossing.
Direct atomic imaging of antiphase boundaries and orthotwins in orientation-patterned GaAs
Authors: dos Reis R. , Ophus C. , Jimenez J. , Snure M. , Gérard B. , Liliental-Weber Z.
Published: March 2013

We use transmission electron microscopy to study orientation-patterned GaAs layers very attractive for applications in terahertz and infrared frequency conversion devices. We observe regularly distributed inversion domains separated by inversion boundaries, together with undesirable microtwin defects originating at these boundaries. Atomic resolution aberration-corrected scanning transmission electron microscopy allowed us to resolve the GaAs dumbbells leading to a direct determination of the growth polarity of particular domains and determination of the alternating Ga-Ga and As-As bonds at the {110}-type antiphase boundary planes. We also determined observed microtwins as rotation twins called orthotwins, the defect that can cause optical losses.
Thermal stress induced void formation during 450 mm defect free silicon crystal growth and implications for wafer inspection
Authors: Kamiyama E. , Vanhellemont J. , Sueoka K. , Araki K. , Izunome K.
Published: March 2013

When pulling large diameter Si crystals from a melt close to the Voronkov criterion, small changes in pulling speed and thermal gradient can lead to the formation of voids leading to detrimental pits on the polished wafer surface. The creation of voids is mainly due to the lowering of the vacancy formation energy due to increased thermal compressive stress. The small size and low density of the formed voids when pulling crystals close to the Voronkov criterion conditions are a challenge for wafer surface inspection tools and possible solutions are discussed.
Positive and negative magnetocaloric effects in CeSi
Authors: Snyman J. L. , Carleschi E. , Doyle B. P. , Strydom A. M.
Published: March 2013

We present a study of the magnetocaloric effect (MCE) in the commensurate antiferromagnet CeSi. We show that the MCE exhibits both positive and negative components, the former indicative of a magnetic configurational entropy increases upon isothermal magnetisation. We describe the Hamiltonian ℋ of the system as a simple model antiferromagnetic Hamiltonian where spins are ferromagnetically aligned in the ac-plane, while planes are weakly antiferromagnetically coupled along the b-axis (consistent with μSR experimental results). We show that ℋ reproduces both the positive and the negative MCE for applied fields up to 30 kOe, while in larger fields the magnitude of the negative component (indicative of an overall suppression of magnetic configurational entropy) is larger than expected from our model.
Lattice dynamics and disorder-induced contraction in functionalized graphene
Authors: Feng Huang Liang , Zeng Zhi
Published: March 2013

The lattice dynamics and disorder-induced contraction in hydrogenated, fluorinated, and chlorinated graphene are studied by first-principles simulation. The effects of the functionalization on the phonon dispersions, Grüneissen constants, vibrational thermodynamic functions (free energy, internal energy, entropy, and heat capacity), thermal-expansion coefficients, and bulk moduli are systematically investigated. Functionalization changes the chemical-bond length, mass, thickness, vibrational-mode symmetry, and mode number, and subsequently has significant effects on the phonon dispersions and Grüneissen constants. Functionalization generally increases the vibrational thermodynamic functions, and their temperature dependences all present conventional isotope effects. Functionalization suppresses (enhances) the thermal contraction (expansion) of the lattice, due to the increases in the system mass, membrane thickness, and the compressibility of the phonons. Both the lattice-constant variation and the phonon thermalization contribute to the temperature dependence of the bulk modulus. Both pristine and hydrogenated graphene can be viewed as two kinds of materials having the Invar and Elinvar properties. The contribution to the lattice contraction in functionalized graphene from the conformation disorder (about 2.0%) is much larger than that by thermalization (<0.1% at 300 K), which explains the mismatch between the experimental and theoretical lattice constants.
Elastomeric transparent capacitive sensors based on an interpenetrating composite of silver nanowires and polyurethane
Authors: Hu Weili , Niu Xiaofan , Zhao Ran , Pei Qibing
Published: March 2013

Highly flexible transparent capacitive sensors have been demonstrated for the detection of deformation and pressure. The elastomeric sensors employ a pair of compliant electrodes comprising silver nanowire networks embedded in the surface layer of polyurethane matrix, and a highly compliant dielectric spacer sandwiched between the electrodes. The capacitance of the sensor sheets increases linearly with strains up to 60% during uniaxial stretching, and linearly with externally applied transverse pressure from 1 MPa down to 1 kPa. Stretchable sensor arrays consisting of 10 × 10 pixels have also been fabricated by patterning the composite electrodes into X-Y addressable passive matrix.
KCa4(BO3)3:Ln3+ (Ln = Dy, Eu, Tb) phosphors for near UV excited white–light–emitting diodes
Authors: Reddy Allu Amarnath , Das Subrata , Goel Ashutosh , Sen Rupam , Siegel Renée , Mafra Luís , Prakash G. Vijaya , Ferreira José M. F.
Published: March 2013

A series of doped KCa4(BO3)3:Ln3+ (Ln: Dy, Eu and Tb) compositions were synthesized by solid–state reaction method and their photoluminescent properties were systematically investigated to ascertain their suitability for application in white light emitting diodes. The X–ray diffraction (XRD) and nuclear magnetic resonance (MAS–NMR) data indicates that Ln3+–ions are successfully occupied the non–centrosymmetric Ca2+ sites, in the orthorhombic crystalline phase of KCa4(BO3)3 having space group Ama2, without affecting the boron chemical environment. The present phosphor systems could be efficiently excitable at the broad UV wavelength region, from 250 to 350 nm, compatible to the most commonly available UV light–emitting diode (LED) chips. Photoluminescence studies revealed optimal near white–light emission for KCa4(BO3)3 with 5 wt.% Dy3+ doping, while warm white–light (CIE; X = 0.353, Y = 0.369) is obtained at 1wt.% Dy3+ ion concentration. The principle of energy transfer between Eu3+ and Tb3+ also demonstrates the potential white–light from KCa4(BO3)3:Eu3+,Tb3+ phosphor. Whereas, single Tb3+ and Eu3+–doped systems showed bright green (Tb3+) and red (Eu3+) emissions, respectively. Having structural flexibility along with remarkable chemical/thermal stability and suitable quantum efficiency these phosphors can be promising candidates as white–light–emitter for near UV LEDs.
What proportion of sexually transmissible infections and HIV are diagnosed in New South Wales’ public sexual health services compared with other services?
Authors: Bourne Chris , Allen Debbie , Brown Katherine , Davies Stephen C. , McNulty Anna , Smith Don E. , O'Connor Catherine C. , Couldwell Deborah , Jackson Eva , Bolton Michale , Rodgers Craig , Konecny Pam , Smith David J. , Parker Angela
Published: March 2013

Background: In New South Wales (NSW), publicly funded sexual health services (PFSHSs) target the populations at greatest risk for important sexually transmissible infections (STIs) and so may make a large contribution to the diagnosis of notifiable STIs. We aimed to determine the proportions of STIs diagnosed in PFSHSs and notified to the NSW Ministry of Health in 2009, and describe geographical variations. Methods: The number of notifiable STIs (infectious syphilis, gonorrhoea, HIV and chlamydia) diagnosed in 2009 was obtained for each Area Health Service (AHS) and each PFSHS. The proportion of diagnoses made by PFSHSs was calculated at the state and AHS level according to five geographical regions: inner and outer metropolitan, regional, rural and remote. Results: The overall proportions of diagnoses made by NSW PFSHSs were syphilis, 25%; gonorrhoea, 25%; HIV, 21%; and chlamydia, 14%. Within each zone, the proportions of these STIs were (respectively): (i) inner metropolitan: 32%, 26%, 21% and 13%; (ii) outer metropolitan: 41%, 24%, 43% and 9%; (iii) regional: 62%, 15%, 23% and 10%; (iv) rural: 8%, 29%, <5% and 20%; and (v) remote: <5%, 43%, <5% and 29%. There was considerable variation in proportions of STIs between and within AHSs (<5–100%). Conclusions: NSW PFSHSs contribute a large proportion of diagnoses for syphilis, gonorrhoea and HIV, but less so for chlamydia. Across AHSs and zones, there was considerable variation in the proportions. These data support the role of PFSHS in identifying and managing important STIs in high-risk populations.
Is it really crystal clear that using methamphetamine (or other recreational drugs) causes people to engage in unsafe sex?
Authors: Digiusto Erol , Rawstorne Patrick
Published: March 2013

Many studies have found associations between unsafe sexual behaviour and use of crystal methamphetamine (and many other recreational drugs). Researchers and authors of relevant articles in popular media have often interpreted these associations as meaning that using ‘crystal’ directly causes people to engage in unsafe sex, and that interventions should aim to reduce crystal use in order to reduce the prevalence of sexually transmissible infections such as HIV. There is consistent evidence that crystal users are a high-risk group in terms of sexual behaviour. However, most relevant studies have provided only circumstantial evidence regarding a causal relationship. Promoting the idea that a particular recreational drug is a major direct cause of unsafe sex may have the unintended adverse effect of creating an excuse for engaging in unsafe sex, thereby increasing its use, and may incur opportunity costs by preventing limited available health promotion resources from being directed more usefully. This paper examines the limitations, in terms of demonstrating causality, of various types of study that have been published on this topic in relation to crystal use in particular. Researchers who investigate relationships between recreational drug use and behaviour, including sexual behaviour, should be careful about the wording of their conclusions and recommendations, and should consider the possibly counterproductive ways in which their findings might be represented in the media.
The geographic relationship between sexual health deprivation and the Index of Multiple Deprivation 2010: a comparison of two indices
Authors: Yin Zheng , Conti Stefano , Desai Sarika , Stafford Mai , Slater Wendi , Gill O. Noel , Simms Ian
Published: March 2013

Objectives
To construct an Index of Sexual Health Deprivation (ISHD), examine its sensitivity, investigate the association between the ISHD and the Index of Multiple Deprivation 2010 (IMD2010), and interpret the observed geographic variation. Methods: The modified IMD method was informed by the IMD2010. Thirteen profiles relating to sexual health were selected and grouped into four domains. The observed profile values for each primary care trust (PCT) were smoothed and converted to a normal distribution before principal component analysis. Loadings were used to calculate profile weights. Domain scores were calculated by combining weighted profiles, which were combined to create the ISHD. A Bayesian approach acted as a comparator for the ISHD. Results: Substantial variation in sexual health deprivation was seen across strategic health authorities (SHA). The London SHA had the highest proportion of PCTs (61%) among the most deprived quartile, followed by North-West SHA (29%). More than half of PCTs in East of England (71%), South Central (56%) and South-West (50%) SHAs fell into the least deprived quartile. No PCTs within the East of England, South Central and South-West SHAs were in the most deprived quartile. Only 57% of PCTs were attributed to the same quartile of the ISHD as the IMD2010. The modified IMD method and the Bayesian approach produced consistent results. Conclusions: The ISHD provides a robust picture of the geography of sexual health and shows a weak association with the IMD2010. It can be used to guide public health action to reduce the geographical gradient in sexual health inequality.
Medical male circumcision and HIV risk: perceptions of women in a higher learning institution in KwaZulu-Natal, South Africa
Authors: Mantell Joanne E. , Smit Jennifer A. , Saffitz Jane L. , Milford Cecilia , Mosery Nzwakie , Mabude Zonke , Tesfay Nonkululeko , Sibiya Sibusiso , Rambally Letitia , Masvawure Tsitsi B. , Kelvin Elizabeth A. , Stein Zena A.
Published: March 2013

Background Medical male circumcision (MMC) reduces the risk of HIV acquisition for men in heterosexual encounters by 50–60%. However, there is no evidence that a circumcised man with HIV poses any less risk of infecting his female partner than an uncircumcised man. There may be an additional risk of HIV transmission to female partners during the 6-week healing period and if condoms are used less often after circumcision. The aim was to explore young women’s perspectives on MMC, with a view to developing clear messages about the limitations of MMC in reducing women’s HIV risk. Methods: We explored women’s perspectives on MMC in KwaZulu-Natal, South Africa, with a sample of 30 female tertiary students via four focus groups (two for women only; two mixed gender). Results: In all groups, women communicated a thorough understanding of the partial efficacy of MMC, but believed that others would not understand this concept. Participants noted that MMC affords no direct benefit to women. Most thought that MMC would increase females’ risk of contracting HIV, that circumcised men may engage in risky behaviours and that men would increase their number of sexual partners after circumcision. Participants believed that condom use would decrease after MMC and speculated that men would have sex during the healing period, which could further compromise women’s sexual health. Conclusion: The concerns expressed by women regarding MMC highlight the need for including women in the dialogue about MMC and for clarifying the impact of MMC on HIV risk for women.
Azithromycin: more lethal than chloramphenicol?
Authors: Stratov Ivan , Denholm Justin , Kent Stephen J.
Published: March 2013

Azithromycin is commonly used in sexual health and respiratory medicine, often when the diagnosis is presumptive. A recent article by Ray et al. reported that 1 out of 20 000 courses of low-dose azithromycin was associated with (sudden) cardiovascular death (including 1 out of 4000 courses in high-risk cardiovascular patients), ascribing these deaths to azithromycin itself. Here, we critique the actual study and examine conflicting data from randomised control trials, animal studies and observational data.
Spatial variability of soil organic carbon in a typical watershed in the source area of the middle Dan River, China
Authors: Xu Guo-Ce , Li Zhan-Bin , Li Peng , Lu Ke-Xin , Wang Yun
Published: March 2013

Soil organic carbon (SOC) plays an important role in maintaining and improving soil fertility and quality, in addition to mitigating climate change. Understanding SOC spatial variability is fundamental for describing soil resources and predicting SOC. In this study, SOC content and SOC mass were estimated based on a soil survey of a small watershed in the Dan River, China. The spatial heterogeneity of SOC distribution and the impacts of land-use types, elevation, slope, and aspect on SOC were also assessed. Field sampling was carried out based on a 100 m by 100 m grid system overlaid on the topographic map of the study area, and samples were collected in three soil layers to a depth of 40 cm. In total, 222 sites were sampled and 629 soil samples were collected. The results showed that classical kriging could successfully interpolate SOC content in the watershed. Contents of SOC showed strong spatial heterogeneity based on the values of the coefficient of variation and the nugget ratio, and this was attributed largely to the type of land use. The range of the semi-variograms increased with increasing soil depth. The SOC content in the soil profile decreased as soil depth increased, and there were significant (P < 0.01) differences among the three soil layers. Land use had a great impact on the SOC content. ANOVA indicated that the spatial variation of SOC contents under different land use types was significant (P < 0.05). The SOC mass of different land-use types followed the order grassland > forestland > cropland. Mean SOC masses of grassland, forestland, and cropland at a depth of 0–40 cm were 5.87, 5.61, and 5.07 kg m–2, respectively. The spatial variation of SOC masses under different land-use types was significant (P < 0.05). ANOVA also showed significant (P < 0.05) impact of aspect on SOC mass in soil at 0–40 cm. Soil bulk density played an important role in the assessment of SOC mass. In conclusion, carbon in soils in the source area of the middle Dan River would increase with conversion from agricultural land to forest or grassland.
Mission impossible in Cyprus? Legitimate return to the partnership state revisited
Authors: Berg Eiki , Toomla Raul
Published: March 2013

Cyprus has been divided for far longer than it has been united. There have been many attempts to reconcile conflicting parties but without remarkable success. The two communities — Greek Cypriots and Turkish Cypriots — see the solution to the “Cyprus problem” in opposite terms. Although recent public opinion surveys have concluded that the most preferred option for the Turkish Cypriots would be “independence of the TRNC” and “reunification of the country”, for the Greek Cypriots, there is much less information about the legitimacy of these competing regimes and their respective claims. This paper seeks to fill this gap by identifying different legitimacy sources and their effect on the course of conflict settlement. Somewhat paradoxically it appears that those most strongly identifying themselves with the Republic of Cyprus, and approving the regime legitimacy of the Greek Cypriot government, are actually for status quo and not for the reunification of the country which makes the return to the partnership state mission impossible.
Compact Klein surfaces of genus 5 with a unique extremal disc
Authors: Nakamura Gou
Published: March 2013

A compact (orientable or non-orientable) surface of genus

g
g

is said to be extremal if it contains an extremal disc, that is, a disc of the largest radius determined only by

g
g

. The present paper concerns non-orientable extremal surfaces of genus

5
5

. We represent the surfaces as side-pairing patterns of a hyperbolic regular

24
24

-gon, that is, a generic fundamental region of an NEC group uniformizing each of the surfaces. We also describe the group of automorphisms of the surfaces with a unique extremal disc.
Influence of the probiotic Streptococcus salivarius strain M18 on indices of dental health in children: a randomized double-blind, placebo-controlled trial
Authors: Burton Jeremy P. , Drummond Bernadette K. , Chilcott Chris N. , Tagg John R. , Thomson W. Murray , Hale John D. F. , Wescombe Philip A.
Published: March 2013

The prevalence of dental caries continues to increase, and novel strategies to reverse this trend appear necessary. The probiotic Streptococcus salivarius strain M18 offers the potential to confer oral health benefits as it produces bacteriocins targeting the important cariogenic species Streptococcus mutans, as well as the enzymes dextranase and urease, which could help reduce dental plaque accumulation and acidification, respectively. In a randomized double-blind, placebo-controlled study of 100 dental caries-active children, treatment with M18 was administered for 3 months and the participants were assessed for changes to their plaque score and gingival and soft-tissue health and to their salivary levels of S. salivarius, S. mutans, lactobacilli, β-haemolytic streptococci and Candida species. At treatment end, the plaque scores were significantly (P = 0.05) lower for children in the M18-treated group, especially in subjects having high initial plaque scores. The absence of any significant adverse events supported the safety of the probiotic treatment. Cell-culture analyses of sequential saliva samples showed no differences between the probiotic and placebo groups in counts of the specifically enumerated oral micro-organisms, with the exception of the subgroup of the M18-treated children who appeared to have been colonized most effectively with M18. This subgroup exhibited reduced S. mutans counts, indicating that the anti-caries activity of M18 probiotic treatments may be enhanced if the efficiency of colonization is increased. It was concluded that S. salivarius M18 can provide oral health benefits when taken regularly.
The innovation game: lessons in strategy and managing operations
Authors: Yalabik Baris , Howard Mickey , Roden Sinéad
Published: March 2013

Purpose

This paper seeks to present a teaching tool (the Innovation Game) which aims to demonstrate the challenges of developing an effective innovation strategy in the context of new product development. The goal of the game is to enable participants to experience how strategic and operational choices made in relation to innovation strategy are interrelated and how these choices can impact on new product development success. Specifically the paper aims to explore the impact of choices made in relation to capability accumulation, capacity management and product‐portfolio management.

Design/methodology/approach

After presenting the learning objectives for the game with the support of relevant literature, the paper describes the design of the game and the context in which it was played. The paper reviews feedback (learning outcomes) from formal reflective post‐game sessions with participants. This feedback indicates that the learning objectives have been satisfied.

Findings

Through experiential learning and reflective practice participants learn, for example, that: capabilities need to match the intended strategy; investing in production capacity can be leveraged to aid negotiations with competitors, or it can be used as a bully tactic; and, it sometimes is better to be an R&D “follower” rather than a “leader”. The participants also learn that the alignment of operational and strategic choices is necessary in order to leverage success in developing new products but that the actions and strategies of competitors have a direct impact also and need to be considered carefully.

Research limitations/implications

The teaching tool adopts a participative game playing and reflective learning approach to introduce into class some of the real‐life competitive dynamics of managing new product development and decision making normally confined to the boardroom. While it is argued that the game demonstrates the challenges of developing successful strategy, the game is set in a static context in which certain external contingencies are not accounted for.

Originality/value

Demonstration of the importance of strategy to new product development is particularly difficult because of the longitudinal nature of product development and the tacit nature of the decision making process which often transpires long after projects are completed. The paper posits that the value of the Innovation Game is in reflecting on it as a practical, interactive tool that helps participants appreciate the challenges inherent in strategic and operational decision making related to innovation strategy and new product development success.