bluuebunny/crossref_metadata_2025 huggingface dataset:
Electronic states and nonlinear optical properties of a two‐dimensional hexagonal quantum dot: Effects of impurity, geometrical size and confinement potential
Authors: Rezaei G. , Azami S. M. , Vaseghi B.
Published: March 2012

In the present work, the linear and the third‐order nonlinear optical absorption coefficients as well as refractive‐index changes in a two‐dimensional hexagonal quantum dot with the presence of an impurity are calculated. A matrix diagonalization method is used to calculate energy levels and corresponding wave functions in the effective‐mass approximation. Also, by means of the compact‐density matrix approach the linear and nonlinear optical absorption coefficients and refractive‐index changes are calculated. The effects of the impurity, the size of the dot and the confinement potential on energy eigenvalues, optical absorption coefficients and refractive‐index changes are investigated. It is found that the energy eigenvalues, absorption coefficients and refractive‐index changes are strongly dependent on the dot size, the confinement potential and the effects produced by the impurity.
Magnetic structure and bonding of rare‐earth diboride compounds RB2: First‐principles calculations
Authors: Kacimi S. , Bekkouche B. , Boukortt A. , Zazoua F. , Djermouni M. , Zaoui A.
Published: March 2012

The electronic structure and magnetic behavior of hexagonal rare‐earth diboride RB2 are studied using ab initio density‐functional theory in the DFT + U approach. The effect of the spin–orbit coupling is also investigated and it is found to be a necessary requirement for the accurate description of the magnetic moment. In this paper, we study the magnetic phase stability of RB2 compounds; the band structure and the density of state (DOS) results prove that the coulomb potential and the spin–orbit interaction are keys factors to understand the magnetic properties of these series of materials. In addition, we also explain the behavior of a chemical bond of RB2 compounds through the analysis of the DOS and of the charge density.
Nondestructive investigation of interface states in high‐k oxide films on Ge substrate using X‐ray absorption spectroscopy
Authors: Cho Deok‐Yong , Jung Hyung‐Suk , Yu Il‐Hyuk , Park Won Goo , Cho Suyeon , Kim Useong , Oh Se‐Jung , Park Byeong‐Gyu , Chang Fan‐Hsiu , Lin Hong‐Ji , Hwang Cheol Seong
Published: March 2012

The unoccupied electronic structures of 5 nm thick high permittivity (k) oxides (HfO2, ZrO2, and Al2O3) and SiO2 films on Ge substrates were examined using O K‐edge X‐ray absorption spectroscopy. Comparative studies with those on Si substrates showed contrasts in the conduction bands, which should be due to the formation of interface states. In the Al2O3 and SiO2 films, GeO2 layers are formed at the interface and they suppress in part the formation of detrimental germanate phases. In contrast, in the HfO2 and ZrO2 films, no signature of the Ge‐oxide phase is observed but some germanate phases are expected to prevail, suggesting a degradation of the gate oxide characteristics. (© 2012 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Testing the broad applicability of the PBEint GGA functional and its one‐parameter hybrid form
Authors: Fabiano E. , Constantin Lucian A. , Della Sala F.
Published: March 2012

We review the performance of the PBEint generalized gradient approximation functional (Fabiano et al., Phys. Rev. B 2010, 82, 113104) recently proposed to improve the description of hybrid interfaces, and we introduce its one‐parameter hybrid form (hPBEint). We consider different well‐established benchmarks for energetic and structural properties of molecular and solid‐state systems as well as model systems and newly developed benchmark sets for dipole moments and metal–molecule interactions. We find that PBEint and hPBEint (with 16.67% Hartree–Fock exchange) yield the overall best performance, working well for most of the considered properties and systems and showing a balanced behavior for different problems. In particular, due to their well‐balanced accuracy, they perform well for the description of hybrid metal–molecule interfaces. © 2012 Wiley Periodicals, Inc.
Design of a wireless anchoring and extending micro robot system for gastrointestinal tract
Authors: Lin Wei , Shi Yuting , Jia Zhiwei , Yan Guozheng
Published: March 2012

Background

Diagnosis and treatment using a conventional endoscope in the gastrointestinal (GI) tract are very common nowadays. However, endoscopy has some disadvantages.

Methods

This paper describes a wireless micro‐robot for active locomotion in the GI tract. After design and analysis of the anchoring‐extending gait, two mechanisms were developed to meet the gait requirements. These actuation and transmission mechanisms were demonstrated in detail to explain the gait implementation. The mechanisms were driven by a micro‐brush direct current motor with a micro‐normal module (m = 0.2 mm) gearbox. The force of the mechanisms was tested to guarantee the sufficiency of the gait and the safety of the robot. After mounting a dedicated video capture unit and wireless power receiving coils, in vitro experiments were conducted to show the feasibility of locomotion by wireless power supply.

Results

The assembled micro‐robot was 13 mm in diameter and 90 mm in length, with a velocity of 1 mm/s at 500 mW power consumption.

Conclusions

The proposed anchoring and extending intestinal micro‐robot met the requirements of intestinal disease diagnosis and treatment. Copyright © 2012 John Wiley & Sons, Ltd.
Parametric stress distribution and displacement functions for tall buildings under lateral loads
Authors: Rahgozar Reza , Ahmadi Ali Reza , Ghelichi Mostafa , Goudarzi Younes , Malekinejad Mohsen , Rahgozar Peyman
Published: March 2012

In this study, effects of applying higher order axial displacement distribution to solve a continuum model for static analysis of the combined system of framed tube, shear core and outrigger–belt truss system in high‐rise buildings are investigated. Framed tube system is modeled using an orthotropic box beam analogy approach and the interaction between shear core and outrigger–belt truss system on framed tube is modeled with rotating spring placed at outrigger–belt truss location. The axial displacement distributions in web and flange panels along structure's height are proposed to be fifth‐order and fourth‐order polynomials, respectively. Analytic analyses are carried out on the basis of the principle of minimum potential energy. A detailed work is carried out through two numerical examples and the accuracy of proposed approximation functions is compared with previous work and finite element analysis. Results demonstrate that the proposed parametric stress distribution and displacement functions are more accurate than previously proposed functions in comparison with the finite element solution. Copyright © 2012 John Wiley & Sons, Ltd.
Numerical investigation of rotational augmentation for S822 wind turbine airfoil
Authors: Gross A. , Fasel H. F. , Friederich T. , Kloker M. J.
Published: March 2012

Direct numerical simulations were carried out for an S822 wind turbine blade section at a chord Reynolds number of Re = 100, 000 and an angle of attack of α = 5°. Results for a stationary non‐rotating blade section compare favorably with wind tunnel data by the University of Illinois at Urbana‐Champaign and XFoil predictions. By adding volume forcing terms to the right‐hand side of the Navier–Stokes equations, the Coriolis and centrifugal accelerations resulting from blade rotation are modeled in the blade section simulations. Blade rotation is shown to delay separation especially near the hub, resulting in a lift increase of up to 100% and a drag reduction. The simulations provide insight into a physical mechanism that offers an explanation for the lift increase observed for rotating blade sections when compared with stationary blade sections, which is commonly referred to as rotational augmentation. Rotation is shown to lead to a radial velocity component toward the blade tip in areas where the velocity is substantially different from its free‐stream value, such as near the stagnation point and especially in the separated flow region, and to the appearance of stationary and traveling crossflow vortices. A linear stability theory analysis that compares favorably with the simulation data provides proof that the primary instabilities are of a mixed type, including both a two‐dimensional mode (Tollmien–Schlichting and Kelvin–Helmholtz type) and a stationary and unsteady crossflow mode. The crossflow instabilities accelerate transition, leading to separation delay, lift increase and drag reduction. This effect is very pronounced at 20% blade radius and still present at 80% radius. Because periodicity conditions were applied in the spanwise direction, the present results provide an explanation for rotational augmentation that is not based on the transfer of fluid from the inboard region toward the blade tip (‘centrifugal pumping’). For the low Reynolds number conditions considered here, crossflow instabilities, which destabilize the flow leading to earlier transition and a separation delay, may contribute to rotational augmentation. Copyright © 2012 John Wiley & Sons, Ltd.
Adrenalectomy Improves Outcomes of Selected Patients with Metastatic Carcinoma
Authors: Vazquez Bianca J. , Richards Melanie L. , Lohse Christine M. , Thompson Geoffrey B. , Farley David R. , Grant Clive S. , Huebner Marianne , Moreno Jose
Published: March 2012

Background

Indications and survival benefit for adrenalectomy (ADX) in the setting of metastasis are not clearly defined. We aimed to determine which patients with primary malignancies may benefit from ADX performed for metastasis. Mayo Clinic institutional outcomes in patients with metastatic disease to the adrenal(s) treated by adrenalectomy were compared to stage‐matched historical controls from the Surveillance Epidemiology and End Results (SEER) database.

Methods

A retrospective review (1992–2010) was conducted to identify patients treated with ADX for metastatic cancer at Mayo Clinic, Rochester. Associations of clinical, surgical, and pathologic features with overall survival (OS) were evaluated using Cox proportional regression models. OS for those treated with ADX was compared with that for SEER database stage‐matched patients who underwent primary resection without resection of distant disease using log‐rank tests.

Results

A total of 166 patients underwent ADX for metastatic primaries involving the kidney 60, lung 24, sarcoma 19, colon 15, pancreas 13, and other‐35. Patients with sarcoma and kidney, lung, and pancreatic tumors who underwent ADX had better OS at 1, 2, and 3 years than did the SEER‐matched controls. Respectively, the rates were for sarcoma (100, 93, 86% vs. 57, 36, 30%), kidney (86, 80, 72% vs. 55, 37, 27%), lung (91, 69, 52% vs. 52, 34, 25%), and pancreas (79, 56, 45% vs. 33, 20, 12%). Univariate analysis identified primary diagnosis <2 years before ADX, other distant site, pancreatic primary, palliative operation, and persistent disease as risk factors for death.

Conclusions

An aggressive surgical approach results in improved OS in patients with metastatic disease arising from soft tissues, kidney, lung, and pancreas. Other tumors may benefit, but larger study cohorts are needed for a meaningful comparison.
Resection of Pulmonary Metastases from Hepatocellular Carcinoma following Liver Transplantation
Authors: Hwang Shin , Kim Yong‐Hee , Kim Dong Kwan , Ahn Chul‐Soo , Moon Deog‐Bok , Kim Ki‐Hun , Ha Tae‐Yong , Song Gi‐Won , Jung Dong‐Hwan , Kim Hyeong Ryul , Park Gil‐Chun , Namgoong Jeong‐Man , Yoon Sam‐Youl , Jung Sung‐Won , Park Seung Il , Lee Sung‐Gyu
Published: March 2012

Background

This study was intended to assess the effect of resection of pulmonary metastasis (PM) of hepatocellular carcinoma (HCC) after liver transplantation (LT). No effective treatment modality exists for PM‐HCC, and little is known about the posttransplant outcomes of pulmonary metastasectomy (PMT).

Methods

Of 587 adult LT recipients diagnosed with HCC, 43 had PM‐HCC. We retrospectively compared outcomes in 23 patients who underwent PMT and 20 who did not. PMT was precluded in ten patients in the non‐PMT group by multiple (usually ≥5) lung nodules, in nine by lung nodules with concurrent or residual extrapulmonary metastasis, and in one by comorbidity.

Results

Of the 23 patients in the PMT group, 14 underwent a single session of PMT, 7 underwent 2 sessions each, and 2 underwent 3 sessions each, for a total of 34 sessions. There were no surgery‐related deaths or complications. After first PMT, 41 nodules, each 0.2–2.5 cm in diameter, were observed: 1–5 nodules per patient. Every available treatment was provided to patients with post‐PMT recurrence and those in the non‐PMT group to control pulmonary and extrapulmonary metastases. Patient survival rates before PM diagnosis did not differ between the two groups (p = 0.141). However, 2 year post‐PM survival rate was significantly greater in the PMT group (30.6% vs. 0%, p = 0.007), resulting in a significantly greater overall 5 year survival rate (44.7% vs. 12.8%, p = 0.017). Univariate analysis showed no risk factor significantly associated with patient survival after PMT.

Conclusions

PMT should be performed for resectable PM‐HCC because it may provide a chance of long‐term survival.
The role of poetry and prose in medical education: the pen as mighty as the scalpel?
Authors: Wolters Frank J. , Wijnen-Meijer Marjo
Published: March 2012

The current medical students’ training on communication skills does not completely fulfil its purpose, since it often lacks attention to the various aspects essential for developing an empathic capacity. Besides having an active component in empathy, cognitive and affective aspects are of equal importance. Integration of arts and humanities courses into the curriculum might bridge this gap. Empathy results mainly from recognition and acknowledgement of a wide spectrum of emotions in patients, their relatives and doctors themselves. Artistic forms of reflection can promote insight into these emotions, complementary to the current teachings which focus on the active component of empathy. Based on several psychological and didactic views, as well as multicentre experience mainly from the United Kingdom and United States, poetry and prose can contribute to sustained development of empathy in medical students.
Total Ankle Arthroplasty: A Brief Review
Authors: Mann Roger A. , Harrison Matthew J.
Published: March 2012

Ankle fusion has long been the standard of treatment for end-stage ankle arthritis, and a successful arthroplasty has been a long sought alternative. It is a motion sparing procedure and may greatly reduce the potential for adjacent level degeneration as seen with arthrodesis. The typical candidate for arthroplasty is a healthy low demand patient, although the indications are widening as the success of the procedure has increased. Nevertheless, it is not fail-safe, technical expertise and experience are necessary to achieve a successful result. We have been treating ankle arthritis with the Scandinavian Total Ankle Replacement (STAR) ankle replacement prosthesis for over ten years. We believe that arthroplasty will surpass arthrodesis as the standard of care for severe ankle arthritis.
Escaping mass approach for inclined plane and round buoyant jets
Authors: Yannopoulos P. C. , Bloutsos A. A.
Published: March 2012

An integral model predicting the mean flow and mixing properties of inclined plane and round turbulent buoyant jets in a motionless environment of uniform density is proposed. The escaping masses from the main buoyant jet flow are simulated, and the model can be successfully applied to initial discharge inclinations${\theta }_{0} $from 90 to$\ensuremath{-} 7{5}^{\ensuremath{\circ} } $with respect to the horizontal plane. This complementary approach introduces a concentration coefficient, which is calibrated using experimental evidence. The present model has incorporated the second-order approach and, regarding the jet-core region, a jet-core model based on the advanced integral model for the production of more correct transverse profiles of the mean axial velocities and mean concentrations than the common Gaussian or top-hat profiles. The partial differential equations for momentum and tracer conservation are written in orthogonal and cylindrical curvilinear coordinates for inclined plane and round buoyant jets, respectively, and they are integrated under the closure assumptions of (a) quasi-linear spreading of the mean flow and mixing fields, and (b) known transverse profile distributions. The integral forms are solved by employing the Runge–Kutta algorithm. Since the most important contribution in the present model is the simulation of the escaping masses, the model has been called the escaping mass approach (EMA). Herein EMA is applied to predict the mean flow properties (trajectory characteristics, mean axial velocities and mean concentrations) for inclined plane and round buoyant jets. The results predicted are compared with experimental data available in the literature, and the accuracy obtained is more than satisfactory. The performance of the EMA is up to 56 % better than using classical integral procedures. EMA can be used for design purposes and for environmental impact assessment studies.
Propagation of capillary waves and ejection of small droplets in rapid droplet spreading
Authors: Ding H. , Li E. Q. , Zhang F. H. , Sui Y. , Spelt P. D. M. , Thoroddsen S. T.
Published: March 2012

A new regime of droplet ejection following the slow deposition of drops onto a near-complete wetting solid substrate is identified in experiments and direct numerical simulations; a coalescence cascade subsequent to pinch-off is also observed for the first time. Results of numerical simulations indicate that the propagation of capillary waves that lead to pinch-off is closely related to the self-similar behaviour observed in the inviscid recoil of droplets, and that motions of the crests and troughs of capillary waves along the interface do not depend on the wettability and surface tension (or Ohnesorge number). The simulations also show that a self-similar theory for universal pinch-off can be used for the time evolution of the pinching neck. However, although good agreement is also found with the double-cone shape of the pinching neck for droplet ejection in drop deposition on a pool of the same liquid, substantial deviations are observed in such a comparison for droplet ejection in rapid drop spreading (including the newly identified regime). This deviation is shown to result from interference by the solid substrate, a rapid downwards acceleration of the top of the drop surface and the rapid spreading process. The experiments also confirm non-monotonic spreading behaviour observed previously only in numerical simulations, and suggest substantial inertial effects on the relation between an apparent contact angle and the dimensionless contact-line speed.
Unsteady turbulent plume models
Authors: Scase M. M. , Hewitt R. E.
Published: March 2012

Four existing integral models of unsteady turbulent plumes are revisited. We demonstrate that none of these published models is ideal for general descriptions of unsteady behaviour and put forward a modified model. We show that the most recent (top-hat) plume model (Scase et al. J. Fluid Mech., vol. 563, 2006, p. 443), and the earlier (Gaussian) plume models (Delichatsios J. Fluid Mech., vol. 93, 1979, p. 241; Yu Trans. ASME, vol. 112, 1990, p.186), are all ill-posed. This ill-posedness arises from the downstream growth of short-scale waves, which have an unbounded downstream growth rate. We show that both the top-hat and the Gaussian (Yu) models can be regularized, rendering them well-posed, by the inclusion of a velocity diffusion term. The effect of including this diffusive mechanism is to include a vertical structure in the model that can be interpreted as representing the vertical extent of an eddy. The effects of this additional mechanism are small for steady applications, and cases where the plume forcing can be considered to follow a power law (both of which have been studied extensively). However, the inclusion of diffusion is shown to be crucial to the general initial-value problem for unsteady models.
Effect of environment and fallow period onCosmopolites sordiduspopulation dynamics at the landscape scale
Authors: Duyck P.-F. , Dortel E. , Vinatier F. , Gaujoux E. , Carval D. , Tixier P.
Published: March 2012

Understanding how the population dynamics of insect pests are affected by environmental factors and agricultural practices is important for pest management. To investigate how the abundance of the banana weevil,Cosmopolites sordidus(Coleoptera: Curculionidae), is related to environmental factors and the length of the fallow period in Martinique, we developed an extensive data set (18,130 observations of weevil abundance obtained with pheromone traps plus associated environmental data) and analysed it with generalized mixed-effects models.

At the island scale,C. sordidusabundance was positively related to mean temperature and negatively related to mean rainfall but was not related to soil type. The number of insects trapped was highest during the driest months of the year. Abundance ofC. sordidusdecreased as the duration of the preceding fallow period increased.

The latter finding is inconsistent with the view that fallow-generated decomposing banana tissue is an important resource for larvae that leads to an increase in the pest population. The results are consistent with the view that fallows, in association with pheromone traps, are effective for the control of the banana weevil.
Why is Quebec Separatism off the Agenda? Reducing National Unity Crisis in the Neoliberal Era
Authors: Changfoot Nadine , Cullen Blair
Published: March 2012

Abstract.The development of federalism in the context of the neoliberal era in the 2000s has partly created the conditions for a more stable co-operation between the federal and Quebec governments, contributing to the trend of separatism being sidelined in Quebec. In the context of neoliberalism, federal–provincial agreements have created conditions for just enough asymmetry in the relationship between the federal government and Quebec, something that Quebec has historically demanded, for separatism to remain off the agenda. What separates this relationship from past ones is a significant change in the context whereby the neoliberal orientation is becoming the common currency for co-operation. If Canadian federalism continues its present course under neoliberalism without any major mishaps, for the first time since the divisive period of the 1990s and early 2000s, federal–Quebec relations likely will be stable without national unity crises of the kind that culminated in the 1980 and 1995 Quebec referenda on sovereignty.

Résumé.Le développement du fédéralisme dans le contexte de l'ère néolibérale dans les années 2000 a en partie créé les conditions pour une coopération plus stable entre les gouvernements fédéral et québécois, contribuant ainsi à la tendance du séparatisme au Québec d'être marginalisés. Dans le contexte du néolibéralisme, des ententes fédérales-provinciales ont créé les conditions pour un peu assez de relation asymétrique entre le gouvernement fédéral et du Québec, quelque chose que le Québec a toujours exigé, au séparatisme de rester hors l'ordre du jour. Ce qui sépare cette relation de celles du passé est un changement significatif dans le contexte dans lequel l'orientation néo-libérale devient la monnaie commune pour la coopération. Si le fédéralisme canadien continue son cours actuel sous le néolibéralisme sans encombre majeur, pour la première fois depuis la période de division des années 1990 et début des années 2000, les relations fédérales-Québec probablement seront stable sans crises unité nationale du genre qui a culminé dans les années 1980 et 1995 référendums sur la souveraineté du Québec.
The Securitization of the US–Canada Border in American Political Discourse
Authors: Salter Mark B. , Piché Geneviève
Published: March 2012

Abstract.In this paper, the authors analyze the empirical process of securitization of the US–Canada border and then reflect on the model proposed by the Copenhagen School. We argue that securitization theory oversimplifies the political process of securitizing moves and audience acceptance. Rather than attributing securitization to a singular speaker addressing a specific audience, we present overlapping and ongoing language security games performed by varying relevant actors during the key period between the Intelligence Reform and Terrorism Prevention Act (IRTPA) in December 2004 and the signing of the Security and Prosperity Partnership of North America (SPP) in June 2005, showing how multiple speakers participate in the continuing construction of a context in which this issue is increasingly treated as a matter of security. We also explore the language adopted by participants in the field, focusing on an expert panel convened by the Homeland Security Institute. We conclude that in the securitization of the US–Canada border there are inconsistencies between truth and discourse, as well as significant distinctions between official and bureaucratic discourses, further emphasizing the importance of a comprehensive model of securitization.

Résumé.Dans cet article, les auteurs font l'analyse du processus empirique de la sécurisation de la frontière Canado-Américaine à travers la réflexion sur le modèle proposé par l'École de Copenhague. Nous soutenons que cette théorie de sécurisation simplifie trop le processus politique de son initiation et de l'acceptation de l'auditeur. Au lieu d'attribuer la sécurisation à un orateur, s'adressant à un public particulier, nous présentons les jeux de langage continuels effectués par plusieurs acteurs pendant la période suivant la Intelligence Reform and Terrorism Prevention Act (IRTPA) en décembre 2004, jusqu'à l'approbation de la Security and Prosperity Partnership of North America (SPP) en juin 2005. Nous maintenons que plusieurs orateurs participent dans la construction continuelle du contexte dans lequel l'affaire est de plus en plus comprise dans le cadre de sécurité. Nous explorons aussi le langage employé par les participants dans le champ, observant surtout un groupe d'experts convoqué au Homeland Security Institute. Nous concluons que dans le cas de la sécurisation de la frontière Canado-Américaine il existe des incohérences entre le discours et le réel, ainsi que des distinctions significatives entre les discours officiels et bureaucratiques, mettant l'accent sur l'importance d'un modèle compréhensif de sécurisation.
The Political Economy of Saving Mothers and Babies: The Politics of State Participation in the Sheppard-Towner Program
Authors: MOEHLING CAROLYN M. , THOMASSON MELISSA A.
Published: March 2012

Enacted in 1922 and repealed in 1929, the Sheppard-Towner program gave federal matching money to states to provide public health education to mothers. We examine variation in state participation in the program, and find that the timing of women's suffrage had an important impact. However, we find that the effect of suffrage was short-lived and did not influence public health spending after the program's repeal. We also find no evidence of a “demonstration effect.” On average, the states that continued activities after Sheppard-Towner ended were those that had sizable public health budgets before the program had even begun.
Law and Peace: Contracts and the Success of the Danish Dairy Cooperatives
Authors: HENRIKSEN INGRID , HVIID MORTEN , SHARP PAUL
Published: March 2012

We consider the successful early emergence of cooperative creameries in Denmark in the late nineteenth century within the framework of the “new institutional economics” presented by Oliver Williamson. Previous work focused on the social cohesion of the Danes, but we demonstrate that this was not sufficient for their success. The Danish legal system, which we compare to that of other countries, was also of crucial importance, along with the way in which rules were monitored and enforced. Of particular interest is the Danish cooperatives’ use of contracts, which we explore with evidence from a variety of primary and secondary sources.
Osaka and Kagoshima Japanese citation tone acoustics: A linguistic-tonetic comparative study
Authors: Ishihara Shunichi
Published: March 2012

The pitch realisations of the accentual systems in Osaka Japanese (OJ) and Kagoshima Japanese (KJ) have been auditorily described in detail, and analysed within various phonological frameworks. However, little linguistic-phonetic descriptive research has been undertaken on the accent types of Japanese dialects in such a way as to enable a cross-dialectal comparison of their acoustic realisation. In this study, linguistic-tonetic representations of OJ and KJ tonalities are derived from normalised acoustic representations for pitch patterns conventionally described as LH, LHL, LLH and LLLH. A comparison of these representations across the two dialects demonstrates some significant differences in the acoustic realisation of the H/L units. The implications of these observed differences for surface tonal representation of KJ within Autosegmental-Metrical theory are also explored.
The intonation of polar questions in Italian: Where is the rise?
Authors: Savino Michelina
Published: March 2012

Earlier studies on Standard Italian describe polar questions as being characterised by a terminal rise, as opposed to a terminal fall for statements, where a low/falling accentual movement precedes the terminal part of the contour in both sentence types. The same is generally claimed for the Northern and Central Italian varieties (including Florentine, i.e. the variety from which Standard Italian stems), whereas Southern accents are characterised by an accentual rise followed by a terminal fall, being therefore the primary cue for question in non-terminal position. However, a closer look at the existing literature on regional Italian question intonation reveals that such a geographical distribution of intonational features across Italian accents is not that clear-cut. A reason for this discrepancy might be the different speaking styles – here intended as the broad spontaneous vs. read distinction – of the spoken productions analysed. The aim of this paper is to call into question the claim that a terminal rise preceded by an accentual low/fall is the most widespread intonational feature for marking questioning across Italian accents. The goal is to provide a clearer picture of question intonation in Italian by looking at the distribution of the rise as either on terminal or non-terminal position across a large number of varieties, where speech materials have been elicited with the same methodology, and they are therefore homogeneous with respect to speaking style. Intonation analysis has been carried out on spontaneous yes–no questions extracted from the Map Task dialogues collected in the CLIPS national corpus (Corpora e Lessici di Italiano Parlato e Scritto – Corpora and Lexicons of Spoken and Written Italian) covering 15 varieties of Italian. Results of this analysis on the Northern, Central, and Southern polar questions reveals that the accentual rise prevails, and that the distribution of the rise across varieties is independent of the geography.
The phonetic implementation of underlying and epenthetic stops in word final clusters in Valencian Catalan
Authors: Recasens Daniel
Published: March 2012

Data for closure duration and the stop burst, as well as on the duration of the adjacent phonetic segments, reveal that speakers of Valencian Catalan produce differently the clusters /lts/ and /ls/, and /rts/ and /rs/, where /t/ is an underlying phoneme in /lts,rts/ and stop epenthesis may occur in /ls,rs/. Only a subset of speakers contrast the production of the nasal cluster pairs /mps/–/ms/ and /nts/–/ns/. Stop epenthesis applies regularly in the sequences /ms,ns,ls, ʎs, ɲs/ but the inserted segment is only phonetically robust in the two latter clusters with an alveolopalatal consonant and to some extent in /ns/, and practically absent in the sequence /rs/. Differences in prominence for the stop consonant, whether underlying or epenthetic, occur as a function of the segmental composition of the cluster, as well as of utterance position and syllable and word affiliation. In conjunction with results from perception tests, it is claimed that these data contribute to our understanding of oral stop deletion after a (quasi-)homorganic consonant in word final clusters without /s/ in other dialects of Catalan and perhaps other languages.
Citing as a Site: Translation and circulation in Muslim South and Southeast Asia
Authors: RICCI RONIT
Published: March 2012

Networks of travel and trade have often been viewed as central to understanding interactions among Muslims across South and Southeast Asia. In this paper I suggest that we consider language and literature as an additional type of network, one that provided a powerful site of contact and exchange facilitated by, and drawing on, citation. I draw on textual sources written in Javanese, Malay, and Tamil between the sixteenth and early twentieth centuries to argue that among Muslim communities in South and Southeast Asia, practices of reading, learning, translating, adapting, and transmitting contributed to the shaping of a cosmopolitan sphere that was both closely connected with the broader, universal Muslim community and rooted in local identities. I consider a series of ‘citation sites’ in an attempt to explore one among many modes of inter-Asian connections, highlighting how citations, simple or brief as they may often seem, are sites of shared memories, history, and narrative traditions and, in the case of Islamic literature, also sites of a common bond to a cosmopolitan and sanctified Arabic.
The effect of spatial heterogenity on the aggregation of ticks on white-footed mice
Authors: DEVEVEY G. , BRISSON D.
Published: March 2012

Parasites are often aggregated on a minority of the individuals in their host populations. Although host characteristics are commonly presumed to explain parasite aggregation on hosts, spatio-temporal aggregation of parasites during their host-seeking stages may have a dominant effect on the aggregation on hosts. We aimed to quantify, using mixed models, repeatability and autocorrelation analyses, the degree to which the aggregation of blacklegged ticks (Ixodes scapularis) on white-footed mice (Peromyscus leucopus) is influenced by spatio-temporal distributions of the host-seeking ticks and by heterogeneity among mice. Host-seeking ticks were spatially aggregated at both the larval and nymphal life-stages. However, this spatial aggregation accounted for little of the variation in larval and nymphal burdens observed on mice (3% and 0%, respectively). Conversely, mouse identity accounted for a substantial proportion of the variance in tick burdens. Mouse identity was a significant explanatory factor as the majority of ticks parasitized a consistent set of mice throughout the activity seasons. Of the characteristics associated with mouse identity investigated, only gender affected larval burdens, and body mass and home range sizes in males were correlated with nymphal burdens. These analyses suggest that aggregation of ticks on a minority of mice does not result from the distribution of host-seeking ticks but from characteristics of the hosts.
Identification and characterization of a novelNeospora caninumimmune mapped protein 1
Authors: CUI X. , LEI T. , YANG D. Y. , HAO P. , LIU Q.
Published: March 2012

Immune mapped protein 1 (IMP1) is a newly discovered protein inEimeria maxima.It is recognized as a potential vaccine candidate againstE. maximaand a highly conserved protein in apicomplexan parasites. Although theNeospora caninumIMP1 (NcIMP1) orthologue ofE. maximaIMP1 was predicted in theN. caninumgenome, it was still not identified and characterized. In this study, cDNA sequence encoding NcIMP1 was cloned by RT-PCR from RNA isolated from Nc1 tachyzoites. NcIMP1 was encoded by an open reading frame of 1182 bp, which encoded a protein of 393 amino acids with a predicted molecular weight of 42·9 kDa. Sequence analysis showed that there was neither a signal peptide nor a transmembrane region present in the NcIMP1 amino acid sequence. However, several kinds of functional protein motifs, including an N-myristoylation site and a palmitoylation site were predicted. Recombinant NcIMP1 (rNcIMP1) was expressed inEscherichia coliand then purified rNcIMP1 was used to prepare specific antisera in mice. Mouse polyclonal antibodies raised against the rNcIMP1 recognized an approximate 43 kDa native IMP1 protein. Immunofluorescence analysis showed that NcIMP1 was localized on the membrane ofN. caninumtachyzoites. The N-myristoylation site and the palmitoylation site were found to contribute to the localization of NcIMP1. Furthermore, the rNcIMP1-specific antibodies could inhibit cell invasion byN. caninumtachyzoitesin vitro. All the results indicate that NcIMP1 is likely to be a membrane protein ofN. caninumand may be involved in parasite invasion.
Natural distribution and co-infection patterns of microsporidia parasites in theDaphnia longispinacomplex
Authors: WEIGL S. , KÖRNER H. , PETRUSEK A. , SEDA J. , WOLINSKA J.
Published: March 2012

Microsporidia are intracellular parasites, frequently infecting the planktonic crustaceanDaphnia.Questioning the ability to detect and identify microsporidia with conventional microscopic techniques, we applied molecular methods in order to investigate the distribution and co-infection patterns of this parasite among 8 communities of theDaphnia longispinahybrid complex. Eight microsporidian taxa were detected, including 3 that previously had not been characterized genetically. Microsporidian communities from nearby lakes were found to be more similar to each other, apparently due to short distance dispersal via secondary hosts. Moreover, we detected seasonal (but not interannual) changes in microsporidian community structure. With some microsporidia being host-specific, these changes might have resulted from seasonal changes in host taxon and clonal composition. The 2 dominant and closely related parasite species were found mainly in single infections, whereas another pair of related microsporidians was found predominantly in co-infections; suggesting species-level differences in the ability to colonize infected hosts. By applying molecular methods, we were not only able to unambiguously identify parasite taxa but also to reveal multiple infections that otherwise would have remained undetected. Given the increased level of accuracy and sensitivity, we highly recommend molecular approaches in future parasite surveys ofDaphniainfections.
Brain activation during fear conditioning in humans depends on genetic variations related to functioning of the hypothalamic–pituitary–adrenal axis: first evidence from two independent subsamples
Authors: Ridder S. , Treutlein J. , Nees F. , Lang S. , Diener S. , Wessa M. , Kroll A. , Pohlack S. , Cacciaglia R. , Gass P. , Schütz G. , Schumann G. , Flor H.
Published: March 2012

Background

Enhanced acquisition and delayed extinction of fear conditioning are viewed as major determinants of anxiety disorders, which are often characterized by a dysfunctional hypothalamic–pituitary–adrenal (HPA) axis.

Method

In this study we employed cued fear conditioning in two independent samples of healthy subjects (sample 1:n=60, sample 2:n=52). Two graphical shapes served as conditioned stimuli and painful electrical stimulation as the unconditioned stimulus. In addition, guided by findings from published animal studies on HPA axis-related genes in fear conditioning, we examined variants of the glucocorticoid receptor and corticotropin-releasing hormone receptor 1 genes.

Results

Variation in these genes showed enhanced amygdala activation during the acquisition and reduced prefrontal activation during the extinction of fear as well as altered amygdala–prefrontal connectivity.

Conclusions

This is the first demonstration of the involvement of genes related to the HPA axis in human fear conditioning.
Relativistic acceleration of micro-foils with prospects for fast ignition
Authors: Eliezer Shalom
Published: March 2012

In this work, it is suggested that the ponderomotive force, induced by a multi-petawatt laser on the interface of a vacuum with solid target, can accelerate a micro-foil to relativistic velocities. The extremely high velocities of the micro-foil can be achieved due to the very short time duration (about a picosecond) of the laser pulse. This accelerated micro-foil is used to ignite a pre-compressed cylindrical shell containing the deuterium tritium fuel. The fast ignition is induced by a heat wave produced during the collision of the accelerated foil with the pre-compressed target. This approach has the advantage of separating geometrically the nanoseconds lasers that compress the target with the picosecond laser that accelerates the foil.
A Fast Multidimensional Scaling Filter for Vehicular Cooperative Positioning
Authors: Efatmaneshnik Mahmoud , Alam Nima , Kealy Allison , Dempster Andrew G
Published: March 2012

Vehicular communication technologies are becoming staples of modern societies. This paper proposes a new positioning algorithm for vehicular networks. The algorithm is a non-classic Multi-Dimensional Scaling Filter (MDSF) that builds on a novel and computationally effective Multi-Dimensional Scaling (MDS) solution covariance estimation technique and also a Maximum Likelihood (ML) filter. In general a major drawback of the non-classic MDS is the high computational cost because of its iterative nature. It is shown that a special blend between vehicular Map-Matching (MM) and MDSF considerably reduces the number of iterations and the convergence time, making the MDSF a suitable algorithm for vehicular network positioning. The performance of MDSF is compared with that of an Extended Kalman Filter (EKF) together with the Cramar Rao Lower Bound (CRLB). It is shown through simulation that for all types of traffic conditions MDSF performs better than EKF and closer to CRLB than EKF. It is also shown that both MDSF and EKF algorithms are robust to typical Global Positioning System (GPS) outages in deep urban canyons. CRLB also proves that Cooperative Positioning (CP) in general has the ability to bridge short GPS outages.
High-Precision Navigation Approach of High-Orbit Spacecraft Based on Retransmission Communication Satellites
Authors: YongZhi Wen , ZeJian Zhang , Jie Wu
Published: March 2012

Many countries have presented new requirements for in-orbit space services. Space autonomous rendezvous and docking technology could speed up the development of in-orbit spacecraft and reduce the threat of increasing amounts of space debris. The purpose of this paper is to provide real-time high-precision navigation data for high-orbit spacecraft, thus reducing the cost of ground monitoring for high-orbit spacecraft autonomous rendezvous operations, and to provide technical support for high-orbit spacecraft in-orbit services. This paper proposes a new high-orbit spacecraft autonomous navigation approach, based on a communication satellite transmitting ground navigation signals. It proposes an overall navigation system design, sets up the system information integration model and analyses the precision of the navigation system by simulation research. Through simulation of this navigation method, the positional precision of a spacecraft at an altitude of 40 000 km, can be within 2·6 m with a velocity precision of 0·0011 m/s. The transponding satellite navigation method greatly reduces the development costs by using communication satellites in high-orbit spacecraft navigation instead of launching special navigation satellites. Moreover, the signals of transponding satellite navigation are generated on the ground, which is very convenient and cost-effective for system maintenance. In addition, placing atomic clocks on the ground may also help improve the clock accuracy achieved. In this study, the satellite-based navigation method is for the first time applied in high-orbit spacecraft navigation. The study's data could improve the present lack of effective high-orbit spacecraft navigation methods and provide strong technical support for autonomous rendezvous and docking of high orbital spacecraft, as well as other application fields.
A Novel Three Dimensional Movement Model for Pedestrian Navigation
Authors: Khider Mohammed , Kaiser Susanna , Robertson Patrick
Published: March 2012

In this paper, a Three Dimensional Pedestrian Movement Model (3D-MM) capable of probabilistically representing pedestrian movement in challenging indoor and outdoor localization environments is developed, implemented and evaluated. In the scope of this paper, the model is used to generate a ‘movement’ or a transition for dynamic positioning systems that are based on sequential Bayesian filtering techniques, such as particle filtering. It can also be used to assign weights for particles' movements proposed by sensors in Likelihood Particle Filters implementations. Alternatively, the developed model can be applied to other applications domains such as infrastructure design, evacuation planning, robot-human interaction and pervasive computing. The novelty of the model is in its ability to characterize both random and goals-oriented pedestrian motions and additionally use the a priori knowledge of maps and floor plans. It will be shown that an appropriate pedestrian movement model not only improves the positioning accuracy, but is also essential for a robust positioning estimator. Additionally, this work shows that maps and floor plans can improve pedestrian movement models but do not replace them, as several authors suggest.
TelOpTrak: Heuristics-enhanced Indoor Location Tracking for Tele-operated Robots
Authors: Borenstein Johann , Miller Russ , Borrell Adam
Published: March 2012

With most tele-operated robots the operator's only feedback is the view from an onboard camera. Live video lets the operator observe the robot's immediate surroundings but does not establish the orientation or whereabouts of the robot in its environment. An additional plot of the robot's trajectory would be helpful for the operator and is sometimes provided, based on GPS. However, indoors where GPS is unavailable, tracking has to rely on dead-reckoning, which is too inaccurate to be useful. Our proposed TelOpTrak method corrects dead-reckoning errors even when only odometry and a low-cost (and thus, high-drift) MEMS-class gyro are available on the robot. TelOpTrak corrects gyro drift by exploiting the structured nature of most buildings, but without having to directly sense building features. This paper explains the TelOpTrak method and provides comprehensive experimental results.

Earlier versions of this paper (Borenstein et al., 2010a), (Borenstein et al., 2010b) were presented at two conferences. The main difference between the earlier conference papers and the present manuscript is that the latter is more comprehensive, more up-to-date, and it presents an entirely new set of experimental results, including results of a live demonstration at the 2010 Robotics Rodeo event at Ft. Benning, USA.