bluuebunny/crossref_metadata_2025 huggingface dataset:
Improving Portfolio Selection Using Option-Implied Volatility and Skewness
Authors: DeMiguel Victor , Plyakha Yuliya , Uppal Raman , Vilkov Grigory
Published: January 2014

Our objective in this paper is to examine whether one can use option-implied information to improve the selection of mean-variance portfolios with a large number of stocks, and to document which aspects of option-implied information are most useful to improve their out-of-sample performance. Portfolio performance is measured in terms of volatility, Sharpe ratio, and turnover. Our empirical evidence shows that using option-implied volatility helps to reduce portfolio volatility. Using option-implied correlation does not improve any of the metrics. Using option-implied volatility, risk premium, and skewness to adjust expected returns leads to a substantial improvement in the Sharpe ratio, even after prohibiting short sales and accounting for transaction costs.
KNOSSIAN GIFTS? TWO LATE MINOAN IIIA1 CUPS FROM TEL BETH-SHEMESH, ISRAEL
Authors: Bunimovitz Shlomo , Lederman Zvi , Hatzaki Eleni
Published: January 2014

Two Late Minoan IIIA1 cups were recently found in the excavations at Tel Beth-Shemesh, Israel. They were part of a larger assemblage of local Late Bronze IIA (first half of the fourteenth centurybc) drinking and eating vessels sealed under a destruction layer in one room of a large edifice, presumably a ‘palace’. A commemorative scarab bearing the name of Amenhotep III and related to the first Jubilee (Sedfestival) in his thirtieth regnal year was found alongside the cups, providing further chronological evidence. This article examines the Late Minoan IIIA1 cups from Beth-Shemesh within their Aegean context and emphasises their close affinity with comparable cups from the palace of Knossos, catalogued and republished here. The Tel Beth-Shemesh cups are the second occurrence – after Sellopoulo Tomb 4 – of Knossian Late Minoan IIIA1 pottery found together with Amenhotep III's scarab. This new evidence strengthens the likelihood of some chronological overlap between Late Minoan IIIA1 and the reign of this Pharaoh. The article also considers the biography of the two Minoan cups, as social agents within the intricate network of the Late Bronze Age palatial gift exchange in the eastern Mediterranean. While it is possible that the cups came to Beth-Shemesh directly from Knossos, another viable option is that they arrived as a gift from the Egyptian court. The two rare Late Minoan IIIA1 Knossian cups could have reached Egypt on the occasion of Amenhotep III's much-discussed official embassy to the Aegean – including Knossos – and then been sent as royal gifts to the ruler of Beth-Shemesh.
Clues for Consequentialists
Authors: BURCH-BROWN JOANNA M.
Published: January 2014

In an influential paper, James Lenman argues that consequentialism can provide no basis for ethical guidance, because we are irredeemably ignorant of most of the consequences of our actions. If our ignorance of distant consequences is great, he says, we can have little reason to recommend one action over another on consequentialist grounds. In this article, I show that for reasons to do with statistical theory, the cluelessness objection is too pessimistic. We have good reason to believe that certain patterns of action will tend to have better consequences, and we have good reason to recommend acting in accordance with strategies based on those advantageous patterns. I close by saying something about the strategies that this argument should lead us to favour.
Service Use, Drop-Out Rate and Clinical Outcomes: A Comparison Between High and Low Intensity Treatments in an IAPT Service
Authors: Chan Stella W. Y. , Adams Malcolm
Published: January 2014

Background: The IAPT services provide high and low intensity psychological treatments for adults suffering from depression and anxiety disorders using a stepped care model. The latest national evaluation study reported an average recovery rate of 42%. However, this figure varied widely between services, with better outcomes associated with higher “step-up” rates between low and high intensity treatments. Aims: This study aimed to compare the two intensity groups in an IAPT service in Suffolk. Method: This study adopted a between groups design. A sample of 100 service users was randomly selected from the data collected from an IAPT service in Suffolk between May 2008 and February 2011. The treatment outcomes, drop-out rate, and other characteristics were compared between those who received high and low intensity treatments. Results: The high intensity group received, on average, more sessions and contact time. They received more CBT sessions and less guided self-help. There were no group differences in terms of the drop-out and appointment cancellation rates. Analyses on clinical outcomes suggested no group difference but demonstrated an overall recovery rate of 52.6% and significant reduction in both depression and anxiety symptoms. Conclusions: Despite methodological limitations, this study concludes that the service as a whole achieved above-average clinical outcomes. Further research building upon the current study in unpacking the relative strengths and weaknesses for the high and low intensity treatments would be beneficial for service delivery.
Genetic diversity and structure of improvedindicarice germplasm
Authors: Wang Kai , Qiu Fulin , Dela Paz Madonna Angelita , Zhuang Jieyun , Xie Fangming
Published: January 2014

The characterization of genetic diversity and structure for improved cultivated varieties/elite lines is tremendously important to assist breeders in parental selection for inbred and hybrid breeding and heterotic group construction. In this study, a total of 737 improvedindicavarieties/lines developed recently and/or widely used by presentindicabreeding programmes worldwide were genotyped with a 384-single-nucleotide polymorphism assay. Model-based population structure analysis revealed the presence of two major groups with six subgroups (SGs), wherein no clear correlation was found between the groups/SGs and breeding programmes or geographical origin of the accessions. Over half of the accessions (51.8%) appeared to have less than 0.6 memberships assigned to any one of the six model-based groups, highlighting the wide range of gene flow within improvedindicavarieties/lines and the genetic integration of valuable alleles shared by ancestries among improved high-yielding varieties/lines through germplasm exchanges. Distance-based clustering revealed that Latin-American cultivatedindicalines have tended to form their own ecological cline, which could serve as a potential heterotic ecotype for hybrid rice breeding, although they are still closely related to Asianindicalines. African cultivatedindicalines, on the other hand, have not yet formed their own ecological cline. It was also observed that the most well-known hybrid rice parents, Zhenshan97B and Minghui63, were unexpectedly clustered in the same SG with a relatively narrow genetic distance, which suggests that a significant genetic distance between parents is not a prerequisite for all elite hybrid rice lines with high heterosis.
Priming effects during the financial crisis: accessibility and applicability mechanisms behind government approval
Authors: Shehata Adam , Falasca Kajsa
Published: January 2014

This study investigates priming effects during the global financial crisis that erupted in September 2008. Using two longitudinal data sources on public opinion dynamics in Sweden between 2007 and 2010, we find no evidence of a basic priming hypothesis. Drawing upon the distinction between accessibility and applicability mechanisms, however, additional analysis indicates that priming of economic considerations was moderated by citizens’ attributions of responsibility for current economic developments. These results support the notion of priming as a two-step process, whereby heavy news coverage of the financial crisis increases theaccessibilityof economic considerations among the audience, but whether these considerations are used in government approval assessments depends on their perceivedapplicabilityas well.
Heritability of DUI Convictions: A Twin Study of Driving Under the Influence of Alcohol
Authors: Anum Emmanuel A. , Silberg Judy , Retchin Sheldon M.
Published: January 2014

Background: The study was undertaken to assess the relative contributions of genetic and environmental influences on drunk-driving. Methods: Driving records of a cohort of male and female twins (N = 17,360) from the Mid-Atlantic Twin Registry were examined. Structural equation models were used to estimate the magnitude of genetic and environmental effects on male and female phenotypes, and test for gender differences. Results: There were significant gender and age effects. Compared with females, males were five times more likely to engage in driving under the influence. Among persons aged 21–49 years, the risk for drunk-driving was eight times that for those aged 50+ years and five times greater than those ≤20 years. In both males and females, aged 21–49 years, a large proportion (57%) of the variance in drunk-driving was due to genetic factors and the remaining 43% due to individual specific environmental influences. Conclusions: Drunk-driving is under significant genetic influence in both males and females. Our findings suggest that a different set of genes influence DUIs in men and women.
Development of a sensitive assay for SERCA activity using FRET detection of ADP
Authors: Jing Meng , Verardi Raffaello , Veglia Gianluigi , Bowser Michael T.
Published: January 2014

A SERCA activity assay which detects ADP productionviatime-resolved FRET is reported, improving sensitivity 50-fold and sample volume 1000-fold.
A triphenylamine-based benzoxazole derivative as a high-contrast piezofluorochromic material induced by protonation
Authors: Xue Pengchong , Chen Peng , Jia Junhui , Xu Qiuxia , Sun Jiabao , Yao Boqi , Zhang Zhenqi , Lu Ran
Published: January 2014

A triphenylamine-based benzoxazole derivative (BVDP) as a typical D–π–A molecule could be used as a low contrast piezofluorochromic material with a spectral red-shift of 29 nm. However, whenBVDPbound a proton to formBVDP+H, a high contrast piezofluorochromism (Δλ= 75 nm) could be observed.
New insight into the potential energy landscape and relaxation pathways of photoexcited aniline from CASSCF and XMCQDPT2 electronic structure calculations
Authors: Sala Matthieu , Kirkby Oliver M. , Guérin Stéphane , Fielding Helen H.
Published: January 2014

New insight into the nonadiabatic relaxation dynamics of aniline following excitation to its first three singlet excited states, 11ππ*, 11π3s/πσ* and 21ππ*.
Conformational transitions in the Ramachandran space of amino acids using the dynamic rotational isomeric state (DRIS) model
Authors: Bayrak Cigdem Sevim , Erman Burak
Published: January 2014

We present a computational method to investigate conformational transitions of the twenty amino acids based on molecular dynamics (MD) simulations and the dynamic rotational isomeric state (DRIS) model. Local dynamics of twenty amino acids resulting from rotational transitions between isomeric states are analyzed.
Selective and reversible photochemical derivatization of cysteine residues in peptides and proteins
Authors: Arumugam Selvanathan , Guo Jun , Mbua Ngalle Eric , Friscourt Frédéric , Lin Nannan , Nekongo Emmanuel , Boons Geert-Jan , Popik Vladimir V.
Published: January 2014

Substrates equipped with the 3-(hydroxymethyl)-2-naphthol moiety (NQMP) are efficiently and selectively photo-ligated to solvent-exposed cysteine residues in peptides and proteins.
Interlaced W18O49 nanofibers as a superior catalyst for the counter electrode of highly efficient dye-sensitized solar cells
Authors: Zhou Huawei , Shi Yantao , Dong Qingshun , Wang Yanxiang , Zhu Chao , Wang Liang , Wang Ning , Wei Ying , Tao Shengyang , Ma Tingli
Published: January 2014

Sufficient contact, high catalytic activity, free electron transport and ionic diffusion are desired for liquid–solid heterogeneous electrocatalysis.
Novel series of quaternary fluoride nanocrystals: room-temperature synthesis and down-shifting/up-converting multicolor fluorescence
Authors: He Xianghong , Yan Bing
Published: January 2014

A straightforward wet-chemical approach to phase-pure M2NaScF6 (M = K, Rb, Cs) quaternary fluoride nanocrystals at ambient conditions has been developed. Down-shifting and up-conversion multicolor fluorescence was generated by incorporating photo-active lanthanide dopants into these host lattices at room temperature.
Hydrogen effects in dilute III-N-V alloys: From defect engineering to nanostructuring
Authors: Pettinari G. , Felici M. , Trotta R. , Capizzi M. , Polimeni A.
Published: January 2014

The variation of the band gap energy of III-N-V semiconductors induced by hydrogen incorporation is the most striking effect that H produces in these materials. A special emphasis is given here to the combination of N-activity passivation by hydrogen with H diffusion kinetics in dilute nitrides. Secondary ion mass spectrometry shows an extremely steep (smaller than 5 nm/decade) forefront of the H diffusion profile in Ga(AsN) under appropriate hydrogenation conditions. This discovery prompts the opportunity for an in-plane nanostructuring of hydrogen incorporation and, hence, for a modulation of the material band gap energy at the nanoscale. The properties of quantum dots fabricated by a lithographically defined hydrogenation are presented, showing the zero-dimensional character of these novel nanostructures. Applicative prospects of this nanofabrication method are finally outlined.
Flow enhancement in nanotubes of different materials and lengths
Authors: Ritos Konstantinos , Mattia Davide , Calabrò Francesco , Reese Jason M.
Published: January 2014

The high water flow rates observed in carbon nanotubes (CNTs) have previously been attributed to the unfavorable energetic interaction between the liquid and the graphitic walls of the CNTs. This paper reports molecular dynamics simulations of water flow in carbon, boron nitride, and silicon carbide nanotubes that show the effect of the solid-liquid interactions on the fluid flow. Alongside an analytical model, these results show that the flow enhancement depends on the tube's geometric characteristics and the solid-liquid interactions.
Spin transport in normal metal/insulator/topological insulator coupled to ferromagnetic insulator structures
Authors: Kondo Kenji
Published: January 2014

In this study, we investigate the spin transport in normal metal (NM)/insulator (I)/topological insulator (TI) coupled to ferromagnetic insulator (FI) structures. In particular, we focus on the barrier thickness dependence of the spin transport inside the bulk gap of the TI with FI. The TI with FI is described by two-dimensional (2D) Dirac Hamiltonian. The energy profile of the insulator is assumed to be a square with barrier height V and thickness d along the transport-direction. This structure behaves as a tunnel device for 2D Dirac electrons. The calculation is performed for the spin conductance with changing the barrier thickness and the components of magnetization of FI layer. It is found that the spin conductance decreases with increasing the barrier thickness. Also, the spin conductance is strongly dependent on the polar angle θ, which is defined as the angle between the axis normal to the FI and the magnetization of FI layer. These results indicate that the structures are promising candidates for novel tunneling magnetoresistance devices.
Numerical analysis of atomic density distribution in arc driven negative ion sources
Authors: Yamamoto T. , Shibata T. , Kashiwagi M. , Hatayama A. , Sawada K. , Hanada M.
Published: January 2014

The purpose of this study is to calculate atomic (H0) density distribution in JAEA 10 ampere negative ion source. A collisional radiative model is developed for the calculation of the H0 density distribution. The non-equilibrium feature of the electron energy distribution function (EEDF), which mainly determines the H0 production rate, is included by substituting the EEDF calculated from 3D electron transport analysis. In this paper, the H0 production rate, the ionization rate, and the density distribution in the source chamber are calculated. In the region where high energy electrons exist, the H0 production and the ionization are enhanced. The calculated H0 density distribution without the effect of the H0 transport is relatively small in the upper region. In the next step, the effect should be taken into account to obtain more realistic H0 distribution.
Optimum phase space probabilities from quantum tomography
Authors: Roy Arunabha S. , Roy S. M.
Published: January 2014

We determine a positive normalised phase space probability distribution P with minimum mean square fractional deviation from the Wigner distribution W. The minimum deviation, an invariant under phase space rotations, is a quantitative measure of the quantumness of the state. The positive distribution closest to W will be useful in quantum mechanics and in time frequency analysis. The position-momentum correlations given by the distribution can be tested experimentally in quantum optics.
An implantable instrument for studying the long-term flight biology of migratory birds
Authors: Spivey Robin J. , Bishop Charles M.
Published: January 2014

The design of an instrument deployed in a project studying the high altitude Himalayan migrations of bar-headed geese (Anser indicus) is described. The electronics of this archival datalogger measured 22 × 14 × 6.5 mm, weighed 3 g, was powered by a ½AA-sized battery weighing 10 g and housed in a transparent biocompatible tube sealed with titanium electrodes for electrocardiography (ECG). The combined weight of 32 g represented less than 2% of the typical bodyweight of the geese. The primary tasks of the instrument were to continuously record a digitised ECG signal for heart-rate determination and store 12-bit triaxial accelerations sampled at 100 Hz with 15% coverage over each 2 min period. Measurement of atmospheric pressure provided an indication of altitude and rate of ascent or descent during flight. Geomagnetic field readings allowed for latitude estimation. These parameters were logged twice per minute along with body temperature. Data were stored to a memory card of 8 GB capacity. Instruments were implanted in geese captured on Mongolian lakes during the breeding season when the birds are temporarily flightless due to moulting. The goal was to collect data over a ten month period, covering both southward and northward migrations. This imposed extreme constraints on the design's power consumption. Raw ECG can be post-processed to obtain heart-rate, allowing improved rejection of signal interference due to strenuous activity of locomotory muscles during flight. Accelerometry can be used to monitor wing-beat frequency and body kinematics, and since the geese continued to flap their wings continuously even during rather steep descents, act as a proxy for biomechanical power. The instrument enables detailed investigation of the challenges faced by the geese during these arduous migrations which typically involve flying at extreme altitudes through cold, low density air where oxygen availability is significantly reduced compared to sea level.
On factors controlling activity of submonolayer bimetallic catalysts: Nitrogen desorption
Authors: Guo Wei , Vlachos Dionisios G.
Published: January 2014

We model N2 desorption on submonolayer bimetallic surfaces consisting of Co clusters on Pt(111) via first-principles density functional theory-based kinetic Monte Carlo simulations. We find that submonolayer structures are essential to rationalize the high activity of these bimetallics in ammonia decomposition. We show that the N2 desorption temperature on Co/Pt(111) is about 100 K higher than that on Ni/Pt(111), despite Co/Pt(111) binding N weaker at low N coverages. Co/Pt(111) has substantially different lateral interactions than single metals and Ni/Pt. The lateral interactions are rationalized with the d-band center theory. The activity of bimetallic catalysts is the result of heterogeneity of binding energies and reaction barriers among sites, and the most active site can differ on various bimetallics. Our results are in excellent agreement with experimental data and demonstrate for the first time that the zero-coverage descriptor, used until now, for catalyst activity is inadequate due not only to lacking lateral interactions but importantly to presence of multiple sites and a complex interplay of thermodynamics (binding energies, occupation) and kinetics (association barriers) on those sites.
Evaluating injection and transport properties of organic field-effect transistors by the convergence point in transfer-length method
Authors: Liu Chuan , Xu Yong , Ghibaudo Gerard , Lu Xubing , Minari Takeo , Noh Yong-Young
Published: January 2014

Contact resistance (RC), which dominates the performance of organic field-effect transistors (OFETs), relates multiple factors such as charge injection, transport, and device architecture. Here, we focus on physical meaning of the convergence point in conventional transfer-length method, and clarify the correlation between charge injection and geometrical parameters of OFETs by simulations. We also defined the effect of band-like/hopping transport in semiconductor on the charge injection process, where less hopping transport results in lower and less gate-voltage dependent RC. These results were confirmed by experiments on pentacene OFETs and reveal the values of convergence point in OFET research.
Ambipolar organic thin-film transistor-based nano-floating-gate nonvolatile memory
Authors: Han Jinhua , Wang Wei , Ying Jun , Xie Wenfa
Published: January 2014

An ambipolar organic thin-film transistor-based nano-floating-gate nonvolatile memory was demonstrated, with discrete distributed gold nanoparticles, tetratetracontane (TTC), pentacene as the floating-gate layer, tunneling layer, and active layer, respectively. The electron traps at the TTC/pentacene interface were significantly suppressed, which resulted in an ambipolar operation in present memory. As both electrons and holes were supplied in the channel and trapped in the floating-gate by programming/erasing operations, respectively, i.e., one type of charge carriers was used to overwrite the other, trapped, one, a large memory window, extending on both sides of the initial threshold voltage, was realized.
Development of a general method for obtaining the geometry of microfluidic networks
Authors: Razavi Mohammad Sayed , Shirani Ebrahim , Salimpour M. R.
Published: January 2014

In the present study, a general method for geometry of fluidic networks is developed with emphasis on pressure-driven flows in the microfluidic applications. The design method is based on general features of network's geometry such as cross-sectional area and length of channels. Also, the method is applicable to various cross-sectional shapes such as circular, rectangular, triangular, and trapezoidal cross sections. Using constructal theory, the flow resistance, energy loss and performance of the network are optimized. Also, by this method, practical design strategies for the fabrication of microfluidic networks can be improved. The design method enables rapid prediction of fluid flow in the complex network of channels and is very useful for improving proper miniaturization and integration of microfluidic networks. Minimization of flow resistance of the network of channels leads to universal constants for consecutive cross-sectional areas and lengths. For a Y-shaped network, the optimal ratios of consecutive cross-section areas (Ai+1/Ai) and lengths (Li+1/Li) are obtained as Ai+1/Ai = 2−2/3 and Li+1/Li = 2−1/3, respectively. It is shown that energy loss in the network is proportional to the volume of network. It is also seen when the number of channels is increased both the hydraulic resistance and the volume occupied by the network are increased in a similar manner. Furthermore, the method offers that fabrication of multi-depth and multi-width microchannels should be considered as an integral part of designing procedures. Finally, numerical simulations for the fluid flow in the network have been performed and results show very good agreement with analytic results.
High-power pulsed thulium fiber oscillator modulated by stimulated Brillouin scattering
Authors: Tang Yulong , Xu Jianqiu
Published: January 2014

A pulsed ∼2-μm thulium-doped fiber laser passively modulated by distributed stimulated Brillouin scattering achieves 10.2 W average power and >100 kHz repetition rate with a very simple all-fiber configuration. The maximum pulse energy and peak power surpass 100 μJ and 6 kW, respectively. Another distinct property is that the pulse width is clamped around 17 ns at all power levels. All the average-power, pulse energy, and peak power show the highest values from passively modulated fiber lasers in all wavelength regions.
Density functional study of CaN mono and bilayer on Cu(001)
Authors: Zahedifar Maedeh , Hashemifar S. Javad , Akbarzadeh Hadi
Published: January 2014

Density functional - pseudopotential calculations are performed to provide first-principles insights into magnetic behaviour of bulk CaN and CaN monolayers on Cu(001) in the rock-salt (RS) and zinc-blende (ZB) structures. Our results indicate that both RS- and ZB-CaN exhibit half-metallic ferromagnetism originated from the incomplete 2p shell of the nitrogen ion. In contrast to the bulk CaN, the CaN monolayers on Cu(001) generally favor ZB structure. We argue that the more stable ZB-CaN thin films on Cu(001) are nonmagnetic, because of strong Cu-N bonding at the interface, while the less stable Ca terminated ZB-CaN thin films exhibit half-metallic ferromagnetism. The transition path between the high energy ferromagnetic and the stable nonmagnetic configurations of the ZB-CaN monolayer on Cu(001) are studied by using the nudged elastic band method. We observe a two stages transition and an activation barrier of about 1.18 eV in the minimum energy path of this transition.
Optical conductivity of Ni1 − xPtx alloys (0<x<0.25) from 0.76 to 6.6 eV
Authors: Abdallah Lina S. , Tawalbeh Tarek M. , Vasiliev Igor V. , Zollner Stefan , Lavoie Christian , Ozcan Ahmet , Raymond Mark
Published: January 2014

Using spectroscopic ellipsometry and Drude-Lorentz oscillator fitting, we determined the dielectric function and optical conductivity versus photon energy from 0.76 to 6.6 eV of 10 nm thick Ni1 − xPtx alloy (0<x<0.25) films deposited on thick thermal oxides. We find absorption peaks near 1.6 and 5.0 eV due to interband optical transitions. There is a significant broadening of the UV peak with increasing Pt content, since the bandwidth of the 3d electrons in Ni is smaller than that of the 5d bands in Pt. Our experimental observation is consistent with ab initio calculations of the density of states for Ni, Pt, and the Ni3Pt compound. Annealing the metals at 500°C for 30 s increases the optical conductivity.
Enhancement of non-resonant dielectric cloaks using anisotropic composites
Authors: Takezawa Akihiro , Kitamura Mitsuru
Published: January 2014

Cloaking techniques conceal objects by controlling the flow of electromagnetic waves to minimize scattering. Herein, the effectiveness of homogenized anisotropic materials in non-resonant dielectric multilayer cloaking is studied. Because existing multilayer cloaking by isotropic materials can be regarded as homogenous anisotropic cloaking from a macroscopic view, anisotropic materials can be efficiently designed through optimization of their physical properties. Anisotropic properties can be realized in two-phase composites if the physical properties of the material are within appropriate bounds. The optimized anisotropic physical properties are identified by a numerical optimization technique based on a full-wave simulation using the finite element method. The cloaking performance measured by the total scattering width is improved by about 2.8% and 25% in eight- and three-layer cylindrical cloaking materials, respectively, compared with multilayer cloaking by isotropic materials. In all cloaking examples, the optimized microstructures of the two-phase composites are identified as the simple lamination of two materials, which maximizes the anisotropy. The same performance as published for eight-layer cloaking by isotropic materials is achieved by three-layer cloaking using the anisotropic material. Cloaking with an approximately 50% reduction of total scattering width is achieved even in an octagonal object. Since the cloaking effect can be realized using just a few layers of the laminated anisotropic dielectric composite, this may have an advantage in the mass production of cloaking devices.
State science academies seek their niche
Authors: Kramer David
Published: January 2014

A fledgling Virginia academy hopes that bringing state scientists together will catalyze interdisciplinary projects.
Clinical features, management and prognosis of multifocal primary bone lymphoma: a retrospective study of the international extranodal lymphoma study group (the IELSG 14 study)
Authors: Messina Carlo , Ferreri Andrés J. M. , Govi Silvia , Bruno‐Ventre Marta , Gracia Medina Elías A. , Porter David , Radford John , Heo Dae S. , Park Hee Y. , Pro Barbara , Jayamohan Jayasingham , Visco Carlo , Scarfò Lydia , Zucca Emanuele , Gospodarowicz Mary , Christie David ,   the International Extranodal Lymphoma Study Group (I.E.L.S.G.)
Published: January 2014

‘Multifocal bone lymphoma’ or ‘polyostotic lymphoma’ is a neoplasm with exclusive multifocal involvement of the skeleton, without affecting lymph nodes or other soft tissues. Knowledge on this uncommon condition is limited because the related literature is sparse and fragmentary. We reviewed cases of multifocal bone diffuse large B‐cell lymphoma (MB‐DLBCL) registered in a clinico‐pathological database of the International Extranodal Lymphoma Study Group that includes 499 cases of bone lymphoma. Clinical features, management and prognosis of 37 MB‐DLBCL patients and 63 ‘controls’ (stage‐IV DLBCL and skeletal involvement) were analysed. Presentation and treatment of MB‐DLBCL and controls were identical. At a median follow‐up of 52 months (10–189), MB‐DLBCL patients exhibited a significantly better response rate (92% vs. 65%; P = 0·002), progression‐free survival (5‐year: 56 ± 9% vs. 34 ± 6%; P = 0·003) and overall survival (5‐year: 74 ± 8% vs. 36 ± 7%; P = 0·002). Among MB‐DLBCL patients, the use of post‐chemo radiotherapy was associated with better overall survival (5‐year: 83 ± 12% vs. 55 ± 16%; P = 0·003). Two MB‐DLBCL patients (5·4%) with spine and skull involvement experienced central nervous system (CNS) relapse. Thus, MB‐DLBCL patients exhibit a significantly better prognosis compared to patients with advanced‐stage DLBCL, and should be treated with conventional anthracycline‐based chemotherapy, keeping intensified treatment for relapsing cases, considering involved‐field radiotherapy, and CNS prophylaxis in high‐risk patients.
Relation between alternations of uplift and subsidence revealed by Late Cenozoic fluvial sequences and physical properties of the continental crust
Authors: Westaway Rob , Bridgland David R.
Published: January 2014

Reversals in vertical crustal motion, alternations between uplift and subsidence over time scales of hundreds of thousands of years or more, have been identified in Late Cenozoic fluvial sequences in many regions worldwide. They form a class of fluvial archive that is distinct from the extreme stability observed in Archaean cratons and the monotonic uplift or subsidence that is widely observed in other regions. Such alternations between uplift and subsidence are characteristic of regions of Early or Middle Proterozoic crust, where the initial crustal consolidation included the development of a thick ‘root’ of mafic material at the base of the crust; the present study focuses on localities with this crustal type in the USA and eastern Europe. It has previously been suggested on the basis of uplift modelling that this style of crustal behaviour occurs only in regions where the mobile lower‐crustal layer is relatively thin. This study supports this conclusion on the basis of independent geothermal calculations, which indicate that such alternations between uplift and subsidence occur where the mobile lower‐crustal layer is ≤∼7 km thick. An understanding of this phenomenon, in relation to the understanding of vertical crustal motions induced by surface processes (and thus by climate change) in general, therefore requires analysis of the properties and dynamics of the mobile lower‐crustal layer; detailed analysis of fluvial sequences thus contributes unique information in this area.
Roving females and patient males: a new perspective on the mating strategies of chimpanzees
Authors: Newton‐Fisher Nicholas E.
Published: January 2014

Mating strategies are sets of decisions aimed at maximizing reproductive success. For male animals, the fundamental problem that these strategies address is attaining mating access to females in a manner that maximizes their chances of achieving paternity. For chimpanzees (Pan troglodytes), despite substantial interest in mating strategies, very little attention has been paid to the most fundamental problem that mating strategies need to solve: finding mates. Only a single model,Dunbar's general model of male mating strategies, exists to explain mate‐searching behaviour in chimpanzees. Under this model, males in most populations are regarded as pursuing a ‘roving’ strategy: searching for and sequestering fertile females who are essentially passive with respect to mate searching. The roving mating strategy is an assumption deeply embedded in the way chimpanzee behaviour is considered; it is implicit in the conventional model for chimpanzee social structure, which posits that male ranging functions both to monitor female reproductive state and to ward these females from other groups of males through collective territoriality: essentially, ranging as mating effort. This perspective is, however, increasingly at odds with observations of chimpanzee behaviour. Herein, I review the logic and evidence for the roving‐male mating strategy and propose a novel alternative, a theoretical framework in which roving is a strategy pursued by female chimpanzees in order to engage successfully in promiscuous mating. Males, unable to thwart this female strategy, instead maximise the number of reproductive opportunities encountered by focusing their behaviour on countering threats to health, fertility and reproductive career. Their prolonged grooming bouts are seen, in consequence, as functioning to mitigate the negative impacts of socially induced physiological stress. In this new framework, the roving‐male strategy becomes, at best, a ‘best of a bad job’ alternative for low‐ranking males when faced with high levels of competition for mating access. Male chimpanzees do not search for mates, but for one another, for food, and, at times, for rivals in other communities. To the extent that female promiscuity functions to counter infanticide risk, mate searching by female chimpanzees—and any associated costs—can be seen as an unavoidable consequence of male sexual coercion. This novel framework is a better fit to the available data than is the conventional account. This review highlights the desperate need for additional work in an area of chimpanzee biology that has been somewhat neglected, perhaps in part because assumptions of roving males have remained unquestioned for too long. It also highlights the need, across taxa, to revisit and revise theory, and to test old assumptions, when faced with contrary data.
Clinic accessibility and clinic‐level predictors of the geographic variation in 2009 pandemic influenza vaccine coverage in Montreal, Canada
Authors: Charland Katia M. , de Montigny Luc , Brownstein John S. , Buckeridge David L.
Published: January 2014

Background

Nineteen mass vaccination clinics were established in Montreal, Canada, as part of the 2009 influenza A/H1N1p vaccination campaign. Although approximately 50% of the population was vaccinated, there was a considerable variation in clinic performance and community vaccine coverage.

Objective

To identify community‐ and clinic‐level predictors of vaccine uptake, while accounting for the accessibility of clinics from the community of residence.

Methods

All records of influenza A/H1N1p vaccinations administered in Montreal were obtained from a vaccine registry. Multivariable regression models, specifically Bayesian gravity models, were used to assess the relationship between vaccination rates and clinic accessibility, clinic‐level factors, and community‐level factors.

Results

Relative risks compare the vaccination rates at the variable's upper quartile to the lower quartile. All else being equal, clinics in areas with high violent crime rates, high residential density, and high levels of material deprivation tended to perform poorly (adjusted relative risk [ARR]: 0·917, 95% CI [credible interval]: 0·915, 0·918; ARR: 0·663, 95% CI: 0·660, 0·666, ARR: 0·649, 95% CI: 0·645, 0·654, respectively). Even after controlling for accessibility and clinic‐level predictors, communities with a greater proportion of new immigrants and families living below the poverty level tended to have lower rates (ARR: 0·936, 95% CI: 0·913, 0·959; ARR: 0·918, 95% CI: 0·893, 0·946, respectively), while communities with a higher proportion speaking English or French tended to have higher rates (ARR: 1·034, 95% CI: 1·012, 1·059).

Conclusion

In planning future mass vaccination campaigns, the gravity model could be used to compare expected vaccine uptake for different clinic location strategies.
Associations Between Bone Mineral Density, Grip Strength, and Lead Body Burden in Older Men
Authors: Khalil Naila , Faulkner Kimberly A. , Greenspan Susan L. , Cauley Jane A. ,   The Osteoporotic Fractures in Men Research Group
Published: January 2014

Objectives

To study the association between blood lead concentration (BPb) and bone mineral density (BMD), physical function, and cognitive function in noninstitutionalized community‐dwelling older men.

Design

Cross‐sectional study.

Setting

University of Pittsburgh clinic, Pittsburgh, Pennsylvania.

Participants

Non‐Hispanic Caucasian men aged 65 and older (N = 445) recruited as a subset of a prospective cohort for the Osteoporotic Fractures in Men Study.

Measurements

BPb was measured in 2007/08. From 2007 to 2009, BMD (g/cm2) was measured using dual‐energy X‐ray absorptiometry. At the same time, physical performance was measured using five tests: grip strength, leg extension power, walking speed, narrow‐walk pace, and chair stands. Cognitive performance was assessed using the modified Mini‐Mental State Examination and the Trail‐Making Test Part B. Participants were categorized into quartiles of BPb. Multivariate regression analysis was used to evaluate the independent relationship between BPb, BMD, and cognitive and physical function.

Results

Mean BPb ± standard deviation was 2.25 ± 1.20 μg/dL (median 2 μg/dL, range 1–10 μg/dL). In multivariate‐adjusted models, men in higher BPb quartiles had lower BMD at femoral neck and total hip (P‐trend < .001 for both). Men with higher BPb had lower age‐adjusted score for grip strength (P‐trend < .001), although this association was not significant in multivariate‐adjusted models (P‐trend < .15). BPb was not associated with lumbar spine BMD, cognition, leg extension power, walking speed, narrow‐walk pace, or chair stands.

Conclusion

Environmental lead exposure may adversely affect bone health in older men. These findings support consideration of environmental exposure in age‐associated bone fragility.
Standardized Patient and Standardized Interdisciplinary Team Meeting: Validation of a New Performance‐Based Assessment Tool
Authors: Yuasa Misuzu , Nagoshi Michael , Oshiro‐Wong Celeste , Tin Maung , Wen Aida , Masaki Kamal
Published: January 2014

The interdisciplinary team (IDT) approach is critical in the care of elderly adults. Performance‐based tools to assess IDT skills have not been well validated. A novel assessment tool, the standardized patient (SP) and standardized interdisciplinary team meeting (SIDTM), consisting of two stations, was developed. First, trainees evaluate a SP hospitalized after a fall. Second, trainees play the role of the physician in a standardized IDT meeting with a standardized registered nurse (SRN) and standardized medical social worker (SMSW) for discharge planning. The SP‐SIDTM was administered to 52 fourth‐year medical students (MS4s) and six geriatric medicine fellows (GMFs) in 2011/12. The SP, SRN, and SMSW scored trainee performance on dichotomous checklists of clinical tasks and Likert scales of communication skills, which were compared according to level of training using t‐tests. Trainees rated the SP‐SIDTM experience as moderately difficult, length of time about right, and believability moderate to high. Reliability was high for both cases (Cronbach α = 0.73–0.87). Interobserver correlation between SRN and SMSW checklist scores (correlation coefficient (r) = 0.82, P < .001) and total scores (r = 0.69, P < .001) were high. The overall score on the SP‐SIDTM case was significantly higher for GMF (75) than for MS4 (65, P = .002). These observations support the validity of this novel assessment tool.
The Migrant Wage Premium in Professional Football: A Superstar Effect?
Authors: Bryson Alex , Rossi Giambattista , Simmons Rob
Published: January 2014

Using panel data on professional footballers and their teams over a seven year period we find a substantial wage premium for migrants which persists within teams and is only partially accounted for by players' on‐field labour productivity. We show that the differential partly reflects the superstar status of migrant workers. This superstar effect is apparent in migrant effects on team performance and crowd attendance.
Kinetics of Memory B Cell and Plasma Cell Responses in the Mice Immunized with Plague Vaccines
Authors: Zhang X. , Wang Q. , Bi Y. , Kou Z. , Zhou J. , Cui Y. , Yan Y. , Zhou L. , Tan Y. , Yang H. , Du Z. , Han Y. , Song Y. , Zhang P. , Zhou D. , Yang R. , Wang X.
Published: January 2014

In our previous studies, we found that plague vaccines can induce long‐term antibody response, but no significant antibody boost was observed when the immunized mice were challenged with virulent Yersinia pestis. However, a booster vaccination of subunit vaccine on week 3 after primary immunization elicited a significantly higher antibody titre than a single dose, whereas no significant antibody titre difference was observed between a single dose and two doses of EV76 vaccination. To address these issues, in this study, we first investigated the kinetics of memory B cells and plasma cells in the mice immunized with EV76 or F1 protein by flow cytometry and then determined antibody titre in five groups of mice immunized with various vaccination strategy. The results showed that memory B cells dropped to a low level at day 56 after primary immunization. In contrast, plasma cells were maintained for more than 98 days. The group with primary immunization of EV76 and booster of F1 antigen developed a higher antibody titre than the group with immunization of F1 antigen and booster of EV76. This result supports a hypothesis that an excess of antigens can neutralize pre‐existing antibodies, and then the redundant antigen induces antibody boost. Taken together, a boost of antibody titre after revaccination may be dependent on the existence of memory B cells and an excess of antigen vaccination. In addition, this study showed an ideal immunization strategy that involves first immunization with a live attenuated vaccine, such as EV76, and then with a subunit vaccine.
Avidity of IgG Antibodies Against Meningococcal Serogroup A Polysaccharide and Correlations with Bactericidal Activity in Sera From Meningitis Patients and Controls From Ethiopia
Authors: Medhane M. , Tunheim G. , Næss L. M. , Mihret W. , Bedru A. , Norheim G. , Petros B. , Aseffa A. , Rosenqvist E.
Published: January 2014

Meningococcal meningitis is a significant global health challenge, especially for sub‐Saharan area: the African meningitis belt. Neisseria meningitidis of serogroup A (MenA) is responsible for the large number of epidemics that have been recorded in these countries. To determine the level of antibodies against meningococcal A polysaccharide (APS) that correlates with protection against MenA disease in the African meningitis belt, it may be important to consider antibody avidity along with quantity. In this study, two ELISA methods using the chaotropic agent ammonium thiocyanate were compared and employed to measure avidity indexes (AI) of IgG antibodies against APS in controls and in acute and convalescent sera from Ethiopian meningococcal patients. High statistical correlations between the AIs determined by the two methods were observed. The geometric mean AI (GMAI) increased with time from acute to convalescent sera indicating affinity maturation. GMAI was significantly higher in convalescent sera from the MenA patients and in sera from the controls than in acute sera from patients with meningococcal disease. A significant correlation between serum bactericidal activity titres (SBA) and concentration of IgG antibodies against APS was observed; however, our results did not indicate that determination of antibody avidities by the thiocyanate elution method gave a better correlation with SBA than anti‐APS IgG concentrations determined by the standard ELISA method.
Cross‐Reactive Immune Response Induced by the Vi Capsular Polysaccharide Typhoid Vaccine Against Salmonella Paratyphi Strains
Authors: Pakkanen S. H. , Kantele J. M. , Kantele A.
Published: January 2014

There are no vaccines in clinical use against paratyphoid fever, caused by Salmonella Paratyphi A and B or, rarely, C. Oral Salmonella Typhi Ty21a typhoid vaccine elicits a significant cross‐reactive immune response against S. Paratyphi A and B, and some reports suggest cross‐protective efficacy against the disease. These findings are ascribed to the O‐12 antigen shared between the strains. The Vi capsular polysaccharide vaccine has been shown to elicit antibodies reactive with O‐9,12. Twenty‐five volunteers immunized with the parenteral Vi vaccine (Typherix®) were explored for plasmablasts cross‐reactive with paratyphoid strains; the responses were compared to those in 25 age‐ and gender‐matched volunteers immunized with Ty21a (Vivotif®). Before vaccination, 48/50 vaccinees had no plasmablasts reactive with the antigens. Seven days after vaccination, 15/25 and 22/25 Vi‐ and Ty21a‐vaccinated volunteers had circulating plasmablasts producing antibodies cross‐reactive with S. Paratyphi A, 18/25 and 23/25 with S. Paratyphi B and 16/25 and 9/25 with Paratyphi C, respectively. Compared to the Ty21a group, the Vi group showed significantly lower responses to S. Paratyphi A and B and higher to S. Paratyphi C. To conclude, the Vi vaccine elicited a cross‐reactive plasmablast response to S. Paratyphi C (Vi antigen in common) and less marked responses to S. Paratyphi A and B than the Ty21a preparation. S. Paratyphi A and B both being Vi‐negative, the result can be explained by trace amounts of bacterial cell wall O‐12 antigen in the Vi preparation, despite purification. The clinical significance of this finding remains to be determined.