bluuebunny/crossref_metadata_2025 huggingface dataset:
Constraint adaptive output regulation of output feedback systems with application to electrostatic torsional micromirror
Authors: Sun Weijie , Lan Jianglin , Yeow John T. W.
Published: November 2013

This paper studies a constraint adaptive output regulation design for a class of nonlinear systems with an unknown exosystem by output feedback control. First, by introducing an internal model with some known design parameter, our concerned problem may be formulated as a specific regulation problem with output constraint. Then, the barrier Lyapunov function technique is further integrated to approach the problem. It is shown that such a constraint adaptive output regulation problem is solvable without constraint violation. In particular, the constructed regulator cannot only keep the boundedness of the closed‐loop system signals but also guarantees the parameter convergence for the unknown parameter vector in the exosystem. As an application, it is illustrated that our result is applicable in tracking the control of an electrostatic torsional micromirror with physical geometry constraint. Copyright © 2013 John Wiley & Sons, Ltd.
A Multisensor Integration Approach toward Astronaut Navigation for Landed Lunar Missions
Authors: Li Rongxing , He Shaojun , Skopljak Boris , Meng Xuelian , Tang Pingbo , Yilmaz Alper , Jiang Jinwei , Oman Charles M. , Banks Martin , Kim Sunah
Published: November 2013

As experienced by Apollo lunar astronauts, spatial orientation can be affected significantly by lunar environmental conditions such as the moon's altered gravity, lack of an atmosphere, limited spatial references, and different level of reflectivity. To help overcome these challenges, a lunar astronaut navigation system called LASOIS (Lunar Astronaut Spatial Orientation and Information System) has been developed. It can significantly reduce spatial disorientation and improve real‐time navigation capability for astronauts exploring the lunar surface. LASOIS is capable of integrating satellite imagery and sensors mounted on the astronaut spacesuit (including inertial measurement units, stereo cameras, and pressure sensors) by an extended Kalman filter algorithm. The processed navigation information is presented through a wrist‐mounted display system. The system has been tested at three field experiment sites, including Moses Lake, WA, Black Lava Point, AZ, and Haleakala National Park, HI. It is demonstrated that the system has achieved an error rate (or relative accuracy) of 2.4% for astronaut navigation over a traverse of 6.1 km in a lunarlike environment.
Typing secure implementation of authentication protocols in environments with compromised principals
Authors: Sattarzadeh Behnam , Fallah Mehran S.
Published: November 2013

Analyzing the executable code, instead of the high‐level model, of security protocols has received attention in recent years. To this end, a number of security type systems have already been proposed. These type systems are sound but incomplete. That is, a well‐typed protocol is certainly secure, whereas no judgment can be made about the protocol whose type‐annotated code is ill typed. In fact, the type‐based analysis of a protocol would have no result unless we are able to find a well‐typed code that represents both the protocol and the attacker's capabilities. As there is a very large space of possible type annotations and adversary models, this requires a profound knowledge of the rationale behind the underlying type system as well as the components of the protocol being analyzed. The problem is aggravated when the protocol runs in environments containing compromised principals. These issues have rendered the use of such type systems somewhat impractical. This paper is an attempt to resolve the problem for authentication protocols in environments containing Dolev–Yao attackers. We concretize our ideas in F5, a security type checker, and suggest effective type annotations and so‐called attacker interfaces representing the capabilities of a general adversary. Copyright © 2013 John Wiley & Sons, Ltd.
Practical JFSL verification using TACO
Authors: Chicote M. , Ciolek D. , Galeotti J.P.
Published: November 2013

Translation of Annotated COde (TACO) is a SAT‐based tool for bounded verification of Java programs. One challenge many formal tools share is to provide a practical interface for a non‐proficient user. In this article, we present an Eclipse plug‐in for the static verifier TACO. This plug‐in allows a user to walk a counterexample trace mimicking a debugging session. TacoPlug (our plug‐in) uses and extends TACO to provide a better debugging experience. TacoPlug interface allows the user to verify an annotated software using the TACO verifier. If TACO finds a violation to the specification, TacoPlug presents it in terms of the annotated source code. TacoPlug features several views of the error trace to facilitate fault understanding. It resembles any software debugger, but the debugging occurs statically without executing the program. Furthermore, should a dynamic analysis be required, TacoPlug presents the user with a unit test case generated by TACO based on the detected violation. We show the usability of our tool by means of a motivational example taken from a real‐life software error. Copyright © 2013 John Wiley & Sons, Ltd.
A Mathematical Approach to the Body–Mind Problem from a System Personality Theory (A Systems Approach to the Body–Mind Problem)
Authors: Micó Joan C. , Caselles Antonio , Amigó Salvador , Cotolí Amparo , Sanz Maria T.
Published: November 2013

The dynamics of both the General Factor of Personality and the personality biological indicators, as a consequence of a stimulus, can be described with a short‐term dynamic model (the response model). The invariance of the response model at both levels of description (psychological and biological) leads to deduce the bridge model with which psychological and biological levels of description can be related. The bridge model is the key tool to deal with the body–mind problem. An application case is presented setting up an experimental design with two subjects. The General Factor of Personality, c‐fos and glutamate dynamics are evaluated as a consequence of a methylphenidate dose intake. The response and bridge models are validated with the outcomes of the application case. Copyright © 2013 John Wiley & Sons, Ltd.
Evaluation of Estimation Models for Multiaxial Fatigue Life
Authors: Zhao Chunyu , Li Xiaopeng , Wen Feng , Gu Xiaobin , Wen Bangchun
Published: November 2013

Some of estimation models for multiaxial fatigue are reviewed. They are the high cycle fatigue (HCF) estimation models based on the Crossland criterion, the Papadopoulos criterion, the Findley criterion, the Matake criterion and the McMiarmid criterion, and the low cycle fatigue (LCF) estimation models based on the Brown and Miller, FS, and SWT parameters, respectively. The HCF estimation models are checked against the experimental data of 30NCD16 steel under fully reversed bending, fully reversed torsion, bending or tension with mean normal stress, multiaxial loading condition. Their fatigue life correlation for the fully reversed torsion tests falls within about 5% for the average absolute value of relative errors. The estimation model based on the Matake criterion can be suitable for all the loading conditions for 30NCD16 steel, its predicted lives fall within the factor three bandwidth. The LCF estimation models are evaluated by the experimental data of 1050 steel under normalized, quenched and tempered, and induction hardened conditions. For 90° out‐of‐phase loading conditions, the predicted lives by the SWT estimation model scatter within the factor three bandwidth for 1050 steel under normalized and quenched and tempered conditions. The average absolute values of estimated errors by the SWT and Brown–Miller estimation models are 10.5 and 11.5%, respectively, for quenched and tempered 1050 steel under in‐phase loading conditions.
On the importance of very long‐term water quality records
Authors: Burt T.P. , Howden N.J.K. , Worrall F.
Published: November 2013

This overview is concerned with the value of long‐term records of water quality in river basin management. In a world where change rather than stasis is increasingly the norm, monitoring is an essential way to discover whether there are significant undesirable changes taking place in the natural environment. The regular collection and processing of information involves systematic and purposeful observation, a deliberate plan of action in which the data have considerable value given the knowledge of their context in time and space. Long‐term data reveal important patterns, which allow trends, cycles, and rare events to be identified. This is particularly important for complex systems where signals may be subtle and slow to emerge. Moreover, very long data sets are essential to test hypotheses undreamt of at the time the measurements were started. This overview includes long time series from UK rivers showing how water quality has changed over time—and continues to change. An important conclusion is the long time frame of system recovery, well beyond the normal lifetime of individual governments. At a time of increasing hydroclimatic variability, long time series of water quality observations remain critically important; continuity of observations is critical at key benchmark sites. WIREs Water 2014, 1:41–48. doi: 10.1002/wat2.1001

This article is categorized under:

Science of Water > Water and Environmental Change

Science of Water > Water Quality
The precarious state of the hydrosphere: why biocultural health matters
Authors: Johnston Barbara Rose , Fiske Shirley J.
Published: November 2013

While the fundamental role of water as a human need and a human right has been acknowledged by the United Nations and member states, too often strategies to secure that right conflict with the competing interests and actions for the same resource. We are approaching a global tipping point in the hydrosphere where the biocultural sustainability of water resources is threatened by the cumulative and synergistic impacts of degenerative changes. When water that sustains life, livelihoods, and culture is threatened, the cultural stability and diversity of peoples and their environment is also threatened. Achieving long‐term sustainability of our hydrosphere requires re‐embedding social, cultural, and environmental concerns within and throughout the local, regional, and global systems that plan, finance, develop, manage, and use our world's water. WIREs Water 2014, 1:1–9. doi: 10.1002/wat2.1003

This article is categorized under:

Human Water > Rights to Water
Dualities near the horizon
Authors: Ferrara Sergio , Marrani Alessio , Orazi Emanuele , Trigiante Mario
Published: November 2013

Abstract

In 4-dimensional supergravity theories, covariant under symplectic electricmagnetic duality rotations, a significant role is played by the symplectic matrix
$ \mathcal{M} $
(φ), related to the coupling of scalars φ to vector field-strengths. In particular, this matrix enters the twisted self-duality condition for 2-form field strengths in the symplectic formulation of generalized Maxwell equations in the presence of scalar fields.

In this investigation, we compute several properties of this matrix in relation to the attractor mechanism of extremal (asymptotically flat) black holes. At the attractor points with no flat directions (as in the
$ \mathcal{N} $
= 2 BPS case), this matrix enjoys a universal form in terms of the dyonic charge vector
$ \mathcal{Q} $
and the invariants of the corresponding symplectic representation
$ {R_{\mathcal{Q}}} $
of the duality group G, whenever the scalar manifold is a symmetric space with G simple and non-degenerate of type E7.

At attractors with flat directions,
$ \mathcal{M} $
still depends on flat directions, but not
$ \mathcal{M}\mathcal{Q} $
, defining the so-called Freudenthal dual of
$ \mathcal{Q} $
itself. This allows for a universal expression of the symplectic vector field strengths in terms of
$ \mathcal{Q} $
, in the near-horizon Bertotti-Robinson black hole geometry.
Towards the spectrum of low-lying particles in supersymmetric Yang-Mills theory
Authors: Bergner G. , Montvay I. , Münster G. , Özugurel U. D. , Sandbrink D.
Published: November 2013

Abstract

The non-perturbative properties of supersymmetric theories are of interest for elementary particle physics beyond the Standard Model. Numerical simulations of these theories are associated with theoretical and technical challenges. The minimal supersymmetric model containing gauge fields is the
$ \mathcal{N}=1 $
supersymmetric Yang-Mills theory. We present the results of our investigations of the masses of the lightest particles of this model on a lattice. The central question is, whether a continuum limit exists with unbroken supersymmetry. In this case the bound states would form mass-degenerate supermultiplets. We have obtained the masses of the gluino-glue particle, mesonic states, and the scalar glueball at a fine lattice spacing. The statistical accuracy as well as the control of finite size effects and lattice artefacts are significantly better than in all previous investigations. Taking the statistical and systematic uncertainties into account, the masses of the fermionic and bosonic states in our present calculations are consistent with the formation of degenerate supermultiplets, indicating that in the continuum limit there is no spontaneous supersymmetry breaking. This new finding is in contrast to previous results.
JIMWLK evolution for multi-particle production in Langevin form
Authors: Iancu E. , Triantafyllopoulos D.N.
Published: November 2013

Abstract

Within the effective theory for the Color Glass Condensate, we study multi-particle production with rapidity correlations in proton-nucleus collisions at high energy. The high-energy evolution responsible for such correlations is governed by a generalization of the JIMWLK equation which describes the simultaneous evolution of the (strong) nuclear color fields in the direct amplitude and the complex conjugate amplitude. This functional equation can be used to derive ordinary evolution equations for the cross-sections for particle production (a generalization of the Balitsky hierarchy). However, the ensuing equations appear to be too complicated to be useful in practice, including in the limit where the number of colors is large. To circumvent this problem, we propose an alternative formulation of the high-energy evolution as a Langevin process, which is better suited for numerical implementations. This process is directly oriented towards the calculation of the cross-sections, so its detailed structure depends upon the nature of the final state. We present the stochastic equations appropriate for two gluon production, and also for three gluon production, with generic rapidity differences.
The discontinuities of conformal transitions and mass spectra of V-QCD
Authors: Areán Daniel , Iatrakis Ioannis , Järvinen Matti , Kiritsis Elias
Published: November 2013

Abstract

Zero temperature spectra of mesons and glueballs are analyzed in a class of holographic bottom-up models for QCD in the Veneziano limit, N

c
→ ∞, N

f
→ ∞, with x = N

f

/N

c
fixed(V-QCD).The back reaction of flavor on color is fully included. It is found that spectra are discrete and gapped (modulo the pions) in the QCD regime, for x below the critical value x
c where the conformal transition takes place. The masses uniformly converge to zero in the walking region
$ x\to {x_{{{c^{-}}}}} $
due to Miransky scaling. All the ratios of masses asymptote to non-zero constants as
$ x\to {x_{{{c^{-}}}}} $
and therefore there is no “dilaton” in the spectrum. The S-parameter is computed and found to be of
$ \mathcal{O}(1) $
in units of N

f

N

c
in the walking regime, while it is always an increasing function of x. This indicates the presence of a subtle discontinuity of correlation functions across the conformal transition at x = x

c
.
The “O'Brien Ethic” as an Interpretative Problem
Authors: Regan John M.
Published: November 2013

The necessity of adopting or redefining illiberal measures—such as torture, internment, or targeted-killings of terrorists—to protect states places burdens on the meaning of liberalism around the world. After 1969, liberal intellectual responses to the so-called Troubles in Northern Ireland identified two conflicted groups of Irish liberals. Then academic and politician Conor Cruise O'Brien attempted to reduce responses to the crisis to the choice between supporting the state and condoning terrorism. “Consenting liberals” compromised professional practices in the law, journalism, broadcasting, and academia to support the state's counterinsurgency. Alternatively, “dissenting liberals” defended their “neutrality” alongside the freedom to criticize the counterinsurgency. Justifying infringements on individual freedoms, O'Brien and others said the democratic state was imperiled. But, anomalously, freedoms were sacrificed in defense of the Irish state, which in security terms did little to defend itself. Nevertheless, the counterinsurgency became an organizing principle in intellectual life, and over forty years colored self-perceptions of Irish society, past and present.
Effects of repeated consumption on sensory-enhanced satiety
Authors: Yeomans Martin R. , McCrickerd Keri , Brunstrom Jeffrey M. , Chambers Lucy
Published: November 2013

Previous research has suggested that sensory characteristics of a drink modify the acute satiating effects of its nutrients, with enhanced satiety being evident when a high-energy drink was thicker and tasted creamier. The present study tested whether this modulation of satiety by sensory context was altered by repeated consumption. Participants (n 48) consumed one of four drinks mid-morning on seven non-consecutive days, with satiety responses being measured pre-exposure (day 1), post-exposure (day 6) and at a 1-month follow-up. The drinks combined two levels of energy (lower energy (LE), 326 kJ and higher energy, 1163 kJ) with two levels of satiety-predictive sensory characteristics (low sensory (LS) or enhanced sensory). Test lunch intake 90 min after drink consumption depended on both the energy content and sensory characteristics of the drink before exposure, but on the energy content alone after exposure and at the follow-up. The largest change was an increase in test meal intake over time in the LE/LS condition. The effects on intake were reflected in appetite ratings, with rated hunger and expected filling affected by sensory characteristics and energy content pre-exposure, but were largely determined by energy content post-exposure and at the follow-up. In contrast, a measure of expected satiety reflected sensory characteristics regardless of energy content on all the three test days. Overall, these data suggest that some aspects of the sensory modulation of satiety are changed by repeated consumption, with covert energy becoming more effective in suppressing appetite over time, but also suggest that these behavioural changes are not readily translated into expectations of satiety.
Diets high in fermentable protein and fibre alter tight junction protein composition with minor effects on barrier function in piglet colon
Authors: Richter Jan F. , Pieper Robert , Zakrzewski Silke S. , Günzel Dorothee , Schulzke Joerg D. , Van Kessel Andrew G.
Published: November 2013

Protein fermentation end products may damage the colonic mucosa, which could be counteracted by dietary inclusion of fermentable carbohydrates (fCHO). Although fermentable crude protein (fCP) and fCHO are known to affect microbial ecology, their interactive effects on epithelial barrier function are unknown. In the present study, in a 2 × 2 factorial experiment, thirty-two weaned piglets were fed low-fCP/low-fCHO (14·5 % crude protein (CP)/14·5 % total dietary fibre (TDF)), low-fCP/high-fCHO (14·8 % CP/16·6 % TDF), high-fCP/low-fCHO (19·8 % CP/14·5 % TDF) and high-fCP/high-fCHO (20·1 % CP/18·0 % TDF) diets. After 21–23 d, samples of proximal and distal colonic mucosae were investigated in Ussing chambers with respect to the paracellular and transcytotic passages of macromolecules and epithelial ion transport. The high-fCHO diets were found to reduce the permeability of the distal colon to the transcytotic marker horseradish peroxidase (HRP, 44 kDa;P <0·05) and also reduce the paracellular permeation ofN-hydroxysuccinimide-biotin into the submucosa (443 Da;P <0·05), whereas that of HRP was decreased by the high-fCP diets (P <0·01). Short-circuit current (active ion transport), transepithelial resistance (barrier function) and charge selectivity were largely unaffected in both the segments. However, the high-fCP diets were found to suppress the aldosterone-induced epithelial Na channel activity (P <0·01) irrespective of fCHO inclusion. The high-fCP diets generally reduced the expression of colonic claudin-1, claudin-2 and claudin-3 (P <0·01), while that of claudin-4 was increased by the high-fCHO diets (P <0·01). The high-fCHO diets also altered the ratio between occludin forms (P <0·05) and increased the expression of tricellulin in the proximal colon, which was not observed with high-fCP diets. In conclusion, dietary fCHO and fCP exerted few and largely independent effects on functional measurements, but altered tight junction protein composition in a compensatory way, so that colonic transport and barrier properties were only marginally affected.
A Four-Session Acceptance and Commitment Therapy Based Intervention for Depressive Symptoms Delivered by Masters Degree Level Psychology Students: A Preliminary Study
Authors: Kohtala Aino , Lappalainen Raimo , Savonen Laura , Timo Elina , Tolvanen Asko
Published: November 2013

Background:Depressive symptoms are one of the main reasons for seeking psychological help. Shorter interventions using briefly trained therapists could offer a solution to the ever-rising need for early and easily applicable psychological treatments.Aims:The current study examines the effectiveness of a four-session Acceptance and Commitment Therapy (ACT) based treatment for self-reported depressive symptoms administered by Masters level psychology students.Method:This paper reports the effectiveness of a brief intervention compared to a waiting list control (WLC) group. Participants were randomized into two groups: ACT (n= 28) and waiting list (n= 29). Long-term effects were examined using a 6-month follow-up.Results:The treatment group's level of depressive symptoms (Beck Depression Inventory) decreased by an average of 47%, compared to an average decrease of 4% in the WLC group. Changes in psychological well-being in the ACT group were better throughout, and treatment outcomes were maintained after 6 months. The posttreatment “between-group” and follow-up “with-in group” effect sizes (Cohen'sd) were large to medium for depressive symptoms and psychological flexibility.Conclusions:The results support the brief ACT-based intervention for sub-clinical depressive symptoms when treatment was conducted by briefly trained psychology students. It also contributes to the growing body of evidence on brief ACT-based treatments and inexperienced therapists.
EQUILIBRIUM DYNAMICS IN AN ENDOGENOUS GROWTH MODEL WITH HABIT FORMATION AND ELASTIC LABOR SUPPLY
Authors: Gómez Manuel A.
Published: November 2013

This paper analyzes the dynamics of an endogenous growth model with external habit formation and elastic labor supply. We first derive the conditions for the existence, uniqueness, and saddlepath stability of a feasible steady state with positive long-run growth. The global dynamics of the economy are characterized by phase-diagram analysis. Then we characterize the comparative static effects of shocks in preferences and production parameters analytically. The comparative dynamic effects of the shocks are characterized by phase-diagram analysis.
Regional Cerebral Blood Flow and Arterial Blood Volume and Their Reactivity to Hypercapnia in Hypertensive and Normotensive Rats
Authors: Kim Tae , Richard Jennings J , Kim Seong-Gi
Published: November 2013

Chronic hypertension induces cerebrovascular remodeling, changing the inner diameter and elasticity of arterial vessels. To examine cerebrovascular morphologic changes and vasodilatory impairment in early-stage hypertension, we measured baseline (normocapnic) cerebral arterial blood volume ( CBVa) and cerebral blood flow ( CBF) as well as hypercapnia-induced dynamic vascular responses in animal models. All experiments were performed with young (3 to 4 month old) spontaneously hypertensive rats (SHR) and control Wistar–Kyoto rats (WKY) under ∼1% isoflurane anesthesia at 9.4 Tesla. Baseline regional CBF values were similar in both animal groups, whereas SHR had significantly lower CBVa values, especially in the hippocampus area. As CBF is maintained by adjusting arterial diameters within the autoregulatory blood pressure range, CBVa is likely more sensitive than CBF for detecting hypertensive-mediated alterations. Unexpectedly, hypercapnia-induced CBF and blood-oxygenation-level-dependent (BOLD) response were significantly higher in SHR as compared with WKY, and the CBF reactivity was highly correlated with the BOLD reactivity in both groups. The higher reactivity in early-stage hypertensive animals indicates no significant vascular remodeling occurred. At later stages of hypertension, the reduced vascular reactivity is expected. Thus, CBF and CBVa mapping may provide novel insights into regional cerebrovascular impairment in hypertension and its progression as hypertension advances.
Structural relationships among LiNaMg[PO4]F and Na2M[PO4]F (M = Mn–Ni, and Mg), and the magnetic structure of LiNaNi[PO4]F
Authors: Ben Yahia Hamdi , Shikano Masahiro , Kobayashi Hironori , Avdeev Maxim , Liu Samuel , Ling Chris D.
Published: November 2013

Both structures of LiNaMg[PO4]F and LiNaNi[PO4]F are isostructural and the magnetic structure of LiNaNi[PO4]F can be described as AFM coupling of FM quasi-layers of zigzag edge sharing octahedral chains.
Atomic layer deposition of solid-state electrolyte coated cathode materials with superior high-voltage cycling behavior for lithium ion battery application
Authors: Li Xifei , Liu Jian , Banis Mohammad Norouzi , Lushington Andrew , Li Ruying , Cai Mei , Sun Xueliang
Published: November 2013

A highly lithium ionic conductive solid-state electrolyte coating layer significantly increases cathode performance in lithium ion batteries.
The role of EDEM2 compared with EDEM1 in ricin transport from the endoplasmic reticulum to the cytosol
Authors: Słomińska-Wojewódzka Monika , Pawlik Anna , Sokołowska Iwona , Antoniewicz Jakub , Węgrzyn Grzegorz , Sandvig Kirsten
Published: November 2013

EDEM1 [ER (endoplasmic reticulum)-degradation-enhancing α-mannosidase I-like protein 1] and EDEM2 are crucial regulators of ERAD (ER-associated degradation) that extracts non-native glycoproteins from the calnexin chaperone system. Ricin is a potent plant cytotoxin composed of an A-chain (RTA) connected by a disulfide bond to a cell-binding lectin B-chain (RTB). After endocytic uptake, the toxin is transported retrogradely to the ER, where the enzymatically active RTA is translocated to the cytosol in a similar manner as misfolded ER proteins. This transport is promoted by EDEM1. In the present study we report that EDEM2 is also involved in ricin retrotranslocation out of the ER. However, the role of EDEM1 and EDEM2 in ricin transport to the cytosol seems to differ. EDEM2 promotes ricin retrotranslocation irrespectively of ER translocon accessibility; moreover, co-immunoprecipitation and pull-down studies revealed that more ricin can interact with EDEM2 in comparison with EDEM1. On the other hand, interactions of both lectins with RTA are dependent on the structure of the RTA. Thus our data display a newly discovered role for EDEM2. Moreover, analysis of the involvement of EDEM1 and EDEM2 in ricin retrotranslocation to the cytosol may provide crucial information about general mechanisms of the recognition of ERAD substrates in the ER.
Sign reversal of magnetization and exchange bias field in LaCr0.85Mn0.15O3
Authors: Bora Tribedi , Ravi S.
Published: November 2013

The sign reversal of magnetization is observed in LaCr0.85Mn0.15O3 compound and the maximum magnetic compensation temperature (Tcomp) was at around 100 K. We have also observed negative and positive values of exchange bias field (HEB) having sign reversal at around Tcomp. The value of HEB could be tuned from −2.1 kOe to + 2.6 kOe with change in temperature. The competition between the magnetic moment due to the canted ferromagnetic component of Cr3+ ions and the paramagnetic component of doped Mn3+ ions under the negative internal field gives rise to magnetization reversal. The origin of sign reversal of HEB is discussed in detail.
Direct observation of substrate induced exciton in carbon nanotube
Authors: Ye Lin-Hui , Yu Dang-Min , Wang Sheng , Zhang Zhiyong , Peng Lian-Mao
Published: November 2013

We have successfully measured the electroluminescence spectra of a single-walled carbon nanotube (CNT) grown to serpentine shape on quartz substrate. We observe two emission peaks: One locates at 0.85 eV and is identified as the usual E11 exciton peak, and the other locates at slightly higher energy of 0.94 eV with similar symmetrical line shape and comparable intensity. However, the extra peak is substantially wider and it broadens with increasing current at unusually faster speed. We show that the extra peak is not from interband transitions, and ascribe it to a type of exciton induced by the formation of substrate-CNT superlattice. The periodic surface potential of the substrate modulates the CNT band structure, causes degeneracy lifting and band flattering at the Brillouin zone, and generates the higher energy exciton. For confirmation, a similar device is fabricated using amorphous SiO2 substrate to avoid the formation of the superlattice. Indeed, the extra emission peak disappears.
⟨001⟩ textured polycrystalline current-perpendicular-to-plane pseudo spin-valves using Co2Fe(Ga0.5Ge0.5) Heusler alloy
Authors: Du Ye , Varaprasad B. S. D. Ch. S. , Takahashi Y. K. , Furubayashi T. , Hono K.
Published: November 2013

The orientation dependence of current-perpendicular-to-plane giant-magnetoresistance (CPP-GMR) was investigated by fabricating ⟨001⟩ textured polycrystalline pseudo spin valves (PSVs) with Co2Fe(Ga0.5Ge0.5) (CFGG) Heusler alloy ferromagnetic layers and a Ag spacer. The PSV with 10 nm CFGG annealed at 400 °C exhibited the resistance-change area product (ΔRA) of 5.8 mΩ (MR ratio of 16%), the largest value reported for polycrystalline CPP-(P)SVs. The ⟨001⟩ textured CFGG PSV outperforms the ⟨011⟩ textured CFGG PSV possibly due to the reduced lattice mismatch or improved band matching at the CFGG/Ag interface.
Linear and nonlinear optical properties of GaAs/AlxGa1−xAs/GaAs/AlyGa1−yAs multi-shell spherical quantum dot
Authors: Emre Kavruk Ahmet , Sahin Mehmet , Koc Fatih
Published: November 2013

In this work, the optical properties of GaAs/AlxGa1−xAs/GaAs/AlyGa1−yAs multi-shell quantum dot heterostructure have been studied as a function of Al doping concentrations for cases with and without a hydrogenic donor atom. It has been observed that the absorption coefficient strength and/or resonant absorption wavelength can be adjusted by changing the Al content of inner-barrier and/or outer-barrier regions. Besides, it has been shown that the donor atom has an important effect on the control of the electronic and optical properties of the structure. The results have been presented as a function of the Al contents of the inner-barrier x and outer-barrier y regions and probable physical reasons have been discussed.
Modifying ceria (111) with a TiO2 nanocluster for enhanced reactivity
Authors: Nolan Michael
Published: November 2013

Modification of ceria catalysts is of great interest for oxidation reactions such as oxidative dehydrogenation of alcohols. Improving the reactivity of ceria based catalysts for these reactions means that they can be run at lower temperatures and density functional theory (DFT) simulations of new structures and compositions are proving valuable in the development of these catalysts. In this paper, we have used DFT+U (DFT corrected for on-site Coulomb interactions) to examine the reactivity of a novel modification of ceria, namely, modifying with TiO2, using the example of a Ti2O4 species adsorbed on the ceria (111) surface. The oxygen vacancy formation energy in the Ti2O4–CeO2 system is significantly reduced over the bare ceria surfaces, which together with previous work on ceria-titania indicates that the presence of the interface favours oxygen vacancy formation. The energy gain upon hydrogenation of the catalyst, which is the rate determining step in oxidative dehydrogenation, further points to the improved oxidation power of this catalyst structure.
On the atomic line profiles in high pressure plasmas
Authors: Janssen J. F. J. , Gnybida M. , Suijker J. L. G. , Rijke A. J. , van Dijk J.
Published: November 2013

In a previous contribution to this journal [H. P. Stormberg, J. Appl. Phys. 51(4), 1963 (1980)], Stormberg presented an analytical expression for the convolution of Lorentz and Levy line profiles, which models atomic radiative transitions in high pressure plasmas. Unfortunately, the derivations are flawed with errors and the final expression, while correct, is accompanied by misguiding comments about the meaning of the symbols used therein, in particular the “complex error function.” In this paper, we discuss the broadening mechanisms that give rise to Stormberg's model and present a correct derivation of his final result. We will also provide an alternative expression, based on the Faddeeva function, which has decisive computational advantages and emphasizes the real-valuedness of the result. The MATLAB/Octave scripts of our implementation have been made available on the publisher's website for future reference.
Dynamics of ZnO nanowires immersed in in-plane switching liquid crystal cells
Authors: Tao Yin , Tam Yiu Ho
Published: November 2013

We investigated both numerically and experimentally the dynamics of individual zinc oxide nanowires immersed in an in-plane switching 4-Cyano-4′-pentylbiphenyl liquid crystal cell under switching electric fields. Comparing the motion of nanowires captured by a high-speed video camera with the simulated results allows the interaction among nanowires, liquid crystals, and external electric field to be studied. Our results show that in the nematic phase, the relaxation and response of a nanowire are both controlled by the dielectrophoretic torque induced by the external electric field and the elastic torque arising from the liquid crystals.
Facile Fabrication of Antibacterial Core–Shell Nanoparticles Based on PHMG Oligomers and PAA Networks via Template Polymerization
Authors: Zhang You Wei , Chen Yan , Zhao Jiong Xin
Published: November 2013

Antibacterial core–shell nanoparticles based on poly(hexamethylene guanidine hydrochloride) (PHMG) oligomers and poly(acrylic acid) (PAA) networks are efficiently fabricated via a facile one-step co-polymerization of acrylic acid and N,N′-methylenebisacrylamide on PHMG templates in aqueous solution. Dynamic light scattering, Fourier-transform infrared spectroscopy, and transmission electron microscopy observations were used to characterize the size, morphology, and structure of the nanoparticles, as well as the interactions between the components. Also, the stability of the nanoparticle dispersion against storage, pH value, salt, and temperature was investigated. The results show that the crosslinked PAA/PHMG nanoparticles are stabilized by electrostatic interactions. The core–shell structure of the nanoparticles was confirmed by transmission electron microscopy observation. The size of the nanoparticles increases substantially with extension of storage or with increase of the salt concentration. The nanoparticle dispersion is stable in a pH range of 2.0–4.0. The size change of the nanoparticles with pH of the medium is parabolic, and the minimum size is reached at pH 3.0. A rise of temperature leads to a slight and recoverable size increase of the nanoparticles. Antibacterial efficiency was evaluated quantitatively against Escherichia coli and Staphylococcus aureus by the plating method according to Standard JC/T 897–2002. The antibacterial activity against these two bacteria are both above 99.0 % at a nanoparticle concentration of 5 mg mL–1. This makes the nanoparticle dispersion a good candidate for the application of antibacterial water-based coatings and textiles coating.
Selective Cleavage of Carbamate Protecting Groups from Aziridines with Otera's Catalyst
Authors: Sun Shan , Tirotta Ilaria , Zia Nicholas , Hutton Craig A.
Published: November 2013

Otera’s distannoxane catalyst was found to promote the cleavage of carbamate groups from N-protected aziridines. This method enables the chemoselective cleavage of an aziridinyl N-carbobenzyloxy (Cbz) group in the presence of other N-Cbz groups. The selectivity is due to the longer, weaker N–C bond of aziridinyl carbamates, as inferred through IR and crystallographic analyses.
Hydrological and water-use efficiency implications of geomorphological stratification in palæochannels in the Northern Murray–Darling Basin
Authors: Vanags C. P. , Vervoort R. W.
Published: November 2013

Regional climactic variability coupled with an increasing demand on water has placed an even greater pressure on managers to understand the complex relationships between surface water and groundwater in the Murray–Darling Basin. Based on limited soil sampling combined with geophysical observations, past research has suggested that relic subsurface drainage features (also known as palæochannels) have a higher risk of deep drainage and lateral flow, particularly where water is impounded or applied as irrigation. The aim of this study was to investigate the hydrological behaviour of an irrigated 25-ha site in North-western New South Wales in more detail to predict deep drainage risk in the presence of palæochannel systems. Several years of direct and indirect observations, including soil sampling and groundwater measures, were collected. Coupling the field data with one- and two-dimensional water balance models revealed a more complex behaviour where a palæochannel functions like a large underground drain. In contrast to other studies, this study suggests that the actual palæochannel does not pose a higher drainage risk, but the combination of the palæochannels with the surroundings soils does have a higher deep drainage risk.
Shoot branching in nutrient-limited Trifolium repens is primarily restricted by shortage of root-derived promoter signals
Authors: Thomas Roderick G. , Hay Michael J. M.
Published: November 2013

Two experiments were used to test the hypothesis that regulation of axillary bud outgrowth in nutrient-limited Trifolium repens L. (white clover) is primarily via variation in the net supply of root-derived promoter signal rather than via direct nutrient effects or inhibitory influences from apical or basal tissues. In the first experiment, foliar nutrient applications to a non-rooted portion of a nutrient-limited stem increased nutrient content, size of organs and rate of growth in the treated region but branch development remained suppressed, indicating that nutrient supply does not directly regulate branching. The second experiment, using decapitation and basal branch excision treatments, showed that excision of basal branches had a major stimulatory effect on bud outgrowth whereas decapitation of the primary stem had only a minor effect. This indicates dominant and minor roles in branching regulation for, respectively, root-derived promoter signal(s) and inhibitory apical influences (apical dominance), and that any possible influence of the inhibitory strigolactone pathway on bud outgrowth is captured within the net root-derived promoter influence. Thus, the proposed hypothesis was supported by our results. These findings may be relevant for all species within the group of prostrate nodally-rooting clonal herbs.
6. Prevalence, genotype diversity and determinants of anal HPV infection in high-risk men attending a sexually transmitted infection clinic in Puerto Rico
Authors: Colón-López Vivian , Ortiz Ana Patricia , Del Toro-Mejías Lizbeth , Clatts Michael Craig , Palefsky Joel M.
Published: November 2013

Background
Recent studies in Puerto Rico (PR) have reported an increasing incidence of anal cancer in Puerto Rican men. The objective of this study was to determine the prevalence, genotype distribution and risk factors associated with anal HPV infection among heterosexual men and men who have sex with men (MSM) attending an STI clinic in PR. Methods: We conducted a cross-sectional study of men 18 years and older. A comprehensive survey was administered that included a demographic and behavioural assessment. Logistic regression was performed to determine factors associated with any, high-risk (HR), low-risk (LR) and multiple anal HPV infection. Results: The mean age of the study sample was 38.0 ± 13.5 and 37.7 ± 13.0 years for MSM and heterosexual men, respectively. A third (29.8%) of the study sample reported being MSM. Significant differences were observed in the prevalence of any anal HPV infection for MSM (84.5%) as compared with heterosexual men (45.7%; P < 0.001). Although MSM showed a higher prevalence of both HR and LR HPV types, no significant differences were observed in the bivariate analysis. Overall, HR anal HPV infection was found in 58.5% of the participants. The most common HR types were 53, 58, 68, 51 and 31. Multiple HPV types in the anal canal were found in 50.0% of the sample. Multivariate logistic regression analysis showed that being a MSM was associated with any anal HPV infection (OR = 6.2; 95% CI 1.5, 25.7). Conclusions: Anal HPV is common among sexually active men attending this STI clinic, with a higher likelihood of any anal HPV infection among MSM.
Abnormal development in embryos and hatchlings of the Australian lungfish, Neoceratodus forsteri, from two reservoirs in south-east Queensland
Authors: Kemp Anne
Published: November 2013

Few of the localities currently inhabited by the Australian lungfish, Neoceratodus forsteri, are in pristine condition. Most populations of wild lungfish in south-east Queensland are now isolated in reservoirs. The barriers formed by the building of dams and weirs across natural rivers separate lungfish groups from each other, cut across possible pathways for normal movement in the environment, and have additional and more serious effects. Water levels in reservoirs fluctuate in spring when lungfish are spawning, and do not allow dense stands of submerged aquatic plants to become established. Lungfish need these plants as sites for oviposition, and newly hatched young need them as refuges and sources of food. Potential recruitment of young lungfish in reservoir populations faces another threat, that of anomalous development of the embryos, hatchlings and juveniles, severe enough to kill many embryos within days of oviposition, and destroy the young fish before they are more than a few months old. Similar anomalies are not present in young fish from a river environment raised under identical conditions. Reasons for poor development, which has now been found in two reservoirs, may be related to the diet of the adult lungfish, and possibly to genetic factors.
Appropriation and Explosion in Reforming Language-Games: A Model for Discursive Change
Authors: Mansouri-Zeyni Sina , Rahebi Mohammad-Ali
Published: November 2013

The two of us wroteAnti-Oedipustogether. Since each of us was several, there was already quite a crowd.

—Deleuze and Guattari,A Thousand Plateaus

With the linguistic turn came an ever-increasing tendency to see language as the locus where truths are born, passed along, or modified. As such, postmodern theories have proved highly compatible with postcolonial studies, which have inspired studies of modern Iran as a country that was colonized, only not officially. However, the latter seem to have fallen for extreme abstraction where metaphysical claims abound: presuming constructivist views of language but failing to present a tangible framework, these studies discuss “discursive change” without giving a clue as to what either discourse or change is. Convinced as such, we have adopted Wittgenstein's idea of language-games to present a tangible model for discursive change.
Determining Optimum Temperature for Growth and Survival of Laboratory-Propagated Juvenile Freshwater Mussels
Authors: Carey Caitlin S , Jones Jess W , Hallerman Eric M , Butler Robert S
Published: November 2013

The effects of temperature on growth and survival of laboratory-propagated juvenile freshwater mussels of two federally endangered species, the Cumberlandian combshell Epioblasma brevidens and oyster mussel E. capsaeformis, and one nonlisted species, the wavy-rayed lampmussel Lampsilis fasciola, were investigated to determine optimum rearing temperatures for these species in small water-recirculating aquaculture systems. Juveniles 4–5 months old were held in downweller buckets at five temperatures. Growth and survival of juveniles were evaluated at 2-week intervals for 10 sampling events. At the end of the 20-week experiment, mean growth at 20, 22, 24, 26, and 28°C was, respectively, 0.75, 2.22, 3.27, 4.23, and 4.08 mm for Cumberlandian combshell; 1.35, 3.73, 3.81, 4.90, and 4.70 mm for oyster mussel; and 2.09, 3.96, 4.99, 5.13, and 4.87 mm for wavy-rayed lampmussel juveniles. Generally, temperature was positively correlated with growth of juveniles. Final mean maximum growth occurred at 26°C for all three species, although no significant differences in growth were detected between 26°C and 28°C. The relationship between temperature and survival of juveniles was less clear. Final survival was 82.5, 89.0, 91.0, 89.5, and 93.5% for Cumberlandian combshell; 73.0, 83.5, 78.0, 78.0, and 68.1% for oyster mussel; and 75.0, 89.5, 87.0, 86.5, and 89.5% for wavy-rayed lampmussel juveniles at the five temperature treatments, respectively. Based on the species used in this study, results indicate that 26°C is the optimum temperature to maximize growth of juvenile mussels in downweller bucket systems. The ability to grow endangered juveniles to larger sizes will improve survival in captivity and upon release into the wild and will reduce time spent in hatcheries. As a result, hatcheries can increase their overall production and enhance the likelihood of success of mussel population recovery efforts by federal and state agencies, and other partners.
The histone demethylase LSD1/KDM1A promotes the DNA damage response
Authors: Mosammaparast Nima , Kim Haeyoung , Laurent Benoit , Zhao Yu , Lim Hui Jun , Majid Mona C. , Dango Sebastian , Luo Yuying , Hempel Kristina , Sowa Mathew E. , Gygi Steven P. , Steen Hanno , Harper J. Wade , Yankner Bruce , Shi Yang
Published: November 2013

Histone demethylation is known to regulate transcription, but its role in other processes is largely unknown. We report a role for the histone demethylase LSD1/KDM1A in the DNA damage response (DDR). We show that LSD1 is recruited directly to sites of DNA damage. H3K4 dimethylation, a major substrate for LSD1, is reduced at sites of DNA damage in an LSD1-dependent manner. The E3 ubiquitin ligase RNF168 physically interacts with LSD1 and we find this interaction to be important for LSD1 recruitment to DNA damage sites. Although loss of LSD1 did not affect the initial formation of pH2A.X foci, 53BP1 and BRCA1 complex recruitment were reduced upon LSD1 knockdown. Mechanistically, this was likely a result of compromised histone ubiquitylation preferentially in late S/G2. Consistent with a role in the DDR, knockdown of LSD1 resulted in moderate hypersensitivity to γ-irradiation and increased homologous recombination. Our findings uncover a direct role for LSD1 in the DDR and place LSD1 downstream of RNF168 in the DDR pathway.