bluuebunny/crossref_metadata_2025 huggingface dataset:
Low SAR planar monopole antenna for wireless communication applications
Authors: Elsheakh Dalia M. , Abdallah Esmat A.
Published: June 2013

Simple internal multiband monopole antenna with low specific absorption rate (SAR) for most wireless communication applications is presented in this paper. The proposed antenna is an unequal arms monopole antenna with a meander stripoin the other substrate side. The antenna has a simple structure and it is sufficiently small in size to be easily fitted on the housing of a mobile phone or a universal serial bus (USB) dongle with size 20 × 50 × 0.8 mm3. The antenna is designed to operate in different bands to cover most of allocated wireless communication bands in the frequency range from 0.9 to 6 GHz. The proposed antenna has an acceptable average gain of about 2.75 dBi and an average efficiency of about 85% while providing a monopole radiation pattern in both horizontal and elevation planes, with average half-power beam width of 65° in the elevation plane. The simulation and the experimental results of the antenna are in agreement. The SAR in the human head is investigated by using CST 2012 Microwave Studio Hugo Voxel Model.
Low-Dose Alcohol Effects on Attention in Adolescents
Authors: Scheel Jennifer F. , Schielke Karin , Lautenbacher Stefan , Aust Sabine , Kremer Simone , Wolstein Jörg
Published: June 2013

Objective: Relatively little is known about the effects of low-dose alcohol effects on attentional performance in adolescents. In the present study, we examined these effects compared to those in adults. Method: 44 healthy subjects (21 adolescents and 23 adults) received either an alcoholic cocktail (average blood alcohol concentration: 0.054 %) or a placebo drink (randomized placebo-controlled). Before and after consuming the drink, participants completed tests on Alertness, Working Memory, Flexibility and Divided Attention. Results: Significant effects were found for the subtest Flexibility, which showed less improvement in the adolescents with alcohol compared to the non-alcohol condition and adults. Furthermore, an age-independent alcohol-induced impairment of the subtest Working Memory was observed. Conclusions: These findings point to a particular vulnerability for alcohol effects in adolescents regarding cognitive flexibility.
Do Individual Response Styles Matter?
Authors: Wetzel Eunike , Böhnke Jan R. , Carstensen Claus H. , Ziegler Matthias , Ostendorf Fritz
Published: June 2013

The occurrence of differential item functioning (DIF) for gender indicates that an instrument may not be functioning equivalently for men and women. Aside from DIF effects, item responses in personality questionnaires can also be influenced by response styles. This study analyzes the German NEO-PI-R regarding its differential item functioning for men and women while taking response styles into account. To this end, mixed Rasch models were estimated first to identify latent classes that differed in their response style. These latent classes were identified as extreme response style (ERS) and nonextreme response style (NERS). Then, DIF analyses were conducted separately for the different response styles and compared with DIF results for the complete sample. Several items especially on Neuroticism, Agreeableness, and Conscientiousness facets showed gender-DIF and thus function differentially between men and women. DIF results differed mainly in size between the complete sample and the response style subsamples, though DIF classification was overall consistent between ERS, NERS, and the complete sample.
I Guess You’re Just Not My Type
Authors: Altmann Tobias , Sierau Susan , Roth Marcus
Published: June 2013

We examined the relevance of personality to relationship satisfaction in intimate couples from a typological point of view. Based on a sample of 133 couples, relationship satisfaction was predicted by the personality types of both relationship partners (each self-rated and partner-rated) resulting from the Big Five factors. Furthermore, interrater agreement of personality type and dyadic similarity were also used as predictors. The results showed that self-rated personality was hardly instrumental in predicting relationship satisfaction. For both sexes, relationship satisfaction seemed to depend mainly on how the person‘s personality was rated by his or her partner. Neither interrater agreement nor dyadic similarity had any influence on the relationship satisfaction of men or women. The applicability of the typological approach in this area of research is discussed.
Synthetic mammalian transgene negative autoregulation
Authors: Shimoga Vinay , White Jacob T , Li Yi , Sontag Eduardo , Bleris Leonidas
Published: June 2013

Biological networks contain overrepresented small‐scale topologies, typically called motifs. A frequently appearing motif is the transcriptional negative‐feedback loop, where a gene product represses its own transcription. Here, using synthetic circuits stably integrated in human kidney cells, we study the effect of negative‐feedback regulation on cell‐wide (extrinsic) and gene‐specific (intrinsic) sources of uncertainty. We develop a theoretical approach to extract the two noise components from experiments and show that negative feedback results in significant total noise reduction by reducing extrinsic noise while marginally increasing intrinsic noise. We compare the results to simple negative regulation, where a constitutively transcribed transcription factor represses a reporter protein. We observe that the control architecture also reduces the extrinsic noise but results in substantially higher intrinsic fluctuations. We conclude that negative feedback is the most efficient way to mitigate the effects of extrinsic fluctuations by a sole regulatory wiring.
Planar path following control for stratospheric airship
Authors: Zheng Zewei , Huo Wei
Published: June 2013

A novel planar path following control method for an underactuated stratospheric airship is presented in this study. Firstly, the Guidance‐Based Path Following (GBPF) principle and the Trajectory Linearisation Control (TLC) theory are described. Then, dynamic model of the stratospheric airship is introduced with kinematics and dynamics equations. Based on this model, a path following control strategy integrated GBPF principle and TLC theory is deduced. The designed control system possesses a cascaded structure which consists of guidance law subsystem, attitude control loop and velocity control loop. Stability analysis shows that the controlled closed‐loop system is asymptotically stable. Finally, simulations for the stratospheric airship and flight experimental results for a low‐altitude airship to follow typical paths are illustrated to verify effectiveness of the proposed approach.
Dwell‐time approach to ℒ2 ‐induced gain analysis of discrete‐time switched systems subject to actuator saturation
Authors: Zhai Shidong , Yang Xiao‐Song
Published: June 2013

This study investigates ℒ2 ‐induced gain from the input disturbance to output of discrete‐time switched linear systems subject to actuator saturation. With the state feedback gains adopted beforehand, the authors establish the linear matrix inequalities formulation which estimates the restricted ℒ2 ‐induced gain for this class of switched systems by dwell‐time approach. Then the authors investigate the influence of parameter variations on the restricted ℒ2 ‐induced gain, and present a state feedback design method for a fixed dwell time and an upper bound of restricted ℒ2 ‐induced gain. In addition, the authors investigate the qualitative relationship between disturbances rejection capability and dwell time. A numerical example is provided to illustrate the effectiveness of our obtained results.
Optimal interconnection design for leader–follower coordination with noise
Authors: Yang Wen , Yan Fan , Shi Hongbo
Published: June 2013

In this study, we address a leader–follower coordination problem with noise in a multi‐agent system. In order to minimise the mean‐square deviation of the individual state of followers from the state of the leader, we develop a strategy to select a subset of followers to connect with the leader. We adopt the method of convex optimisation to solve both constant edge weight and different edge weight case. Furthermore, we propose optimised algorithms to find the fastest convergence speed. We also study optimisation problems for leader–follower system with a dynamic leader, and also provide a sufficient condition for the convergence of the expected value of the total mean‐square deviation. Examples and applications of the developed methodology are also discussed.
Multi‐model particle cardinality‐balanced multi‐target multi‐Bernoulli algorithm for multiple manoeuvring target tracking
Authors: Yang Jin‐Long , Ji Hong‐Bing , Ge Hong‐Wei
Published: June 2013

Multiple manoeuvring target tracking is an extremely difficult problem in the target tracking field, especially under the non‐linear systems. The probability hypothesis density (PHD) and cardinalised PHD (CPHD) algorithms based on the particle filter have proved to be promising algorithms for multi‐target tracking. However, they have a heavy computational burden because of the particle clustering in the stage of state extraction. Especially, the additional calculation is added to the CPHD algorithm because of the estimation of the cardinality distribution. To solve the problem, the authors propose a novel multiple manoeuvring target tracking algorithm by extending the multi‐model method to the cardinality‐balanced multi‐target multi‐Bernoulli filter and then using the sequential Monte Carlo implementation. Moreover, in order to obtain the individual target tracks, the particle labelling technique is introduced in the proposed algorithm. Simulation results show that the proposed algorithm can effectively achieve the track continuity for the multiple manoeuvring target tracking and has a higher accuracy of state estimates than the multiple model particle PHD and CPHD algorithm with a better computational efficiency.
Experiments on autonomous Boolean networks
Authors: Rosin David P. , Rontani Damien , Gauthier Daniel J. , Schöll Eckehard
Published: June 2013

We realize autonomous Boolean networks by using logic gates in their autonomous mode of operation on a field-programmable gate array. This allows us to implement time-continuous systems with complex dynamical behaviors that can be conveniently interconnected into large-scale networks with flexible topologies that consist of time-delay links and a large number of nodes. We demonstrate how we realize networks with periodic, chaotic, and excitable dynamics and study their properties. Field-programmable gate arrays define a new experimental paradigm that holds great potential to test a large body of theoretical results on the dynamics of complex networks, which has been beyond reach of traditional experimental approaches.
Oxidation and reduction of size-selected subnanometer Pd clusters on Al2O3 surface
Authors: Mao Bao-Hua , Chang Rui , Lee Sungsik , Axnanda Stephanus , Crumlin Ethan , Grass Michael E. , Wang Sui-Dong , Vajda Stefan , Liu Zhi
Published: June 2013

In this paper, we investigate uniformly dispersed size-selected Pdn clusters (n = 4, 10, and 17) on alumina supports. We study the changes of clustered Pd atoms under oxidizing and reducing (O2 and CO, respectively) conditions in situ using ambient pressure XPS. The behavior of Pd in the clusters is quite different from that of Pd foil under the same conditions. For all Pd clusters, we observe only one Pd peak. The binding energy of this Pd 3d peak is ∼1-1.4 eV higher than that of metallic Pd species and changes slightly in CO and O2 environments. On the Pd foil however many different Pd species co-exist on the surface and change their oxidation states under different conditions. We find that the Pd atoms in direct contact with Al2O3 differ in oxidation state from the surface Pd atoms in a foil under reaction conditions. Compared to previous literature, we find that Pd 3d peak positions are greatly influenced by the different types of Al2O3 supports due to the combination of both initial and final state effects.
Electron dynamics of interatomic Coulombic decay in quantum dots induced by a laser field
Authors: Bande Annika
Published: June 2013

In this paper we investigated the dynamics of an electron in the presence of a time-dependent laser field in a model potential for a two-level single-electron semiconductor quantum dot (QD) that is capable of undergoing interatomic Coulombic decay (ICD) together with an electron bound to a neighboring QD. We demonstrate that ICD can be initiated by coupling the two-level QD to either a continuous or a pulsed moderate to strong laser and we obtain the total and partial decay widths of the resonance excited state in agreement with that from the solely decay of the resonance [A. Bande, K. Gokhberg, and L. S. Cederbaum, J. Chem. Phys. 135, 144112 (2011)10.1063/1.3646205]. A detailed discussion of the effects of direct ionization by the laser in single- or multi-photon process as well as Rabi oscillations is furthermore presented.
Effects of Ni-coating on ZnO nanowires: A Raman scattering study
Authors: Filippov S. , Wang X. J. , Devika M. , Koteeswara Reddy N. , Tu C. W. , Chen W. M. , Buyanova I. A.
Published: June 2013

Structural properties of ZnO/Ni core/shell nanowires (NWs) are studied in detail by means of Raman spectroscopy. It is shown that formation of the Ni shell leads to passivation of surface states responsible for the observed enhanced intensity of the A1(LO) Raman mode of the bare ZnO NWs. It also causes appearance of 490 cm−1 and 710 cm−1 modes that are attributed to local vibrational modes of a defect/impurity (or defects/impurities). This defect is concluded to be preferably formed in annealed ZnO/Ni NWs and is unlikely to contain a Ni atom, as the same Raman modes were also reported for the Ni-free ZnO nanostructures. From our resonant Raman studies, we also show that the ZnO/Ni core/shell NWs exhibit an enhanced Raman signal with a multiline structure involving A1(LO). This observation is attributed to combined effects of an enhanced Fröhlich interaction at the ZnO/Ni heterointerface and coupling of the scattered light with local surface plasmons excited in the Ni shell. The plasmonic effect is also suggested to allow detection of carbon-related species absorbed at the surface of a single ZnO/Ni NW, promising for applications of such structures as efficient nano-sized gas sensors.
Coherent synthesis of terahertz radiation from femtosecond laser filaments in air
Authors: Mitryukovskiy Sergey I. , Liu Yi , Prade Bernard , Houard Aurélien , Mysyrowicz André
Published: June 2013

We report on the coherent synthesis of pulsed terahertz radiation from femtosecond laser filaments organized in an array. The terahertz intensity is proportional to the square of the number of the filaments, which provides a simple method for scaling up of the terahertz energy with a powerful femtosecond laser. Moreover, directional off-axis terahertz radiation can be achieved. This paves the way for applications of this terahertz source for remote sensing.
Synthesis and magnetic properties of large-area ferromagnetic cylindrical nanoshell and nanocup arrays
Authors: Wang Z. , Shimon G. , Liu X. , Thompson C. V. , Ross C. A. , Choi W. K. , Adeyeye A. O.
Published: June 2013

Large-area arrays of magnetic Ni80Fe20 cylindrical nanoshells, nanocups, and perforated nanocups were synthesized using oblique deposition into topographical templates patterned using laser interference lithography. The geometry of the template and the tilt angle of the sample during deposition provide versatile control over the final geometry and dimension of nanostructures with thickness below 10 nm. Decreasing shell thickness led to a magnetization switching path between onion (bidomain) and reverse onion states, bypassing the vortex (flux-closed) state. The variation of magnetization reversal processes with geometry was characterized using vibrating sample magnetometry, and the results were in good agreement with micromagnetic simulations.
Fabrication of carbon nanotubes grown woven carbon fiber/epoxy composites and their electrical and mechanical properties
Authors: Samsur R. , Rangari V. K. , Jeelani S. , Zhang L. , Cheng Z. Y.
Published: June 2013

Multiwall carbon nanotubes (CNTs) were directly grown on woven carbon fibers using chemical vapor deposition technique and iron acetate as a catalyst. These CNTs grown woven carbon fibers were further infused with epoxy resin to fabricate fiber reinforced nanocomposites. Both electric and mechanical properties of these composites were studied and found that the electric resistivity of composite reduced significantly as the amount of CNTs on woven carbon fiber increased. For the neat composite without CNTs, the resistivity observed was 25 Ω·m, while it was only 0.2 Ω·m for the composite with 3.3 wt. % of CNTs grown on woven carbon fiber. The flexure test results showed a 34% increase in strength and 126% increase in stiffness for 1.65 wt. % CNTs grown on woven carbon fiber.
Anti-reflective nanocomposite based coating for crystalline silicon solar cells with noticeable significance
Authors: Gangopadhyay Utpal , Jana Sukhendu , Das Sayan , Ghosh Prajit , Mondal Anup
Published: June 2013

Novel Diamond-like Nanocomposite (DLN) thin film as Anti-Reflective Nanocomposite Based (ARNAB) coating for crystalline silicon (c-Si) solar cell is the main objective of this paper. The DLN film was deposited by plasma assisted chemical vapour deposition (PACVD) method and characterized by Fourier transform infrared, field emission scanning electron microscope, and high resolution transmission emission microscope. Results show that c-Si3N4 and c-SiC nanoparticle (3–5 nm) were embedded in a-C:H matrix, and they were interpenetrated by Si-C bonding, i.e., typical DLN structure. The optical properties of the film were investigated by UV-VIS-near-infrared and photoluminescence spectroscopy. The performance of ARNAB coating was evaluated by measuring the reflectance, external quantum efficiency (EQE), and conversion efficiency. The solar weighted average reflection from textured c-Si was reduced to 2.25% in wavelength range 300 nm–1100 nm, and more than 90% EQE of the solar cell was achieved within the broad wavelength range 560 nm–870 nm. The result has been also compared with conventional silicon nitride anti-reflection coating (ARC). Finally, 0.8% absolute increased of efficiency was achieved with ARNAB layer in comparison with silicon nitride AR coating. The ARNAB thin film has a great potential to be used as ARC for silicon based solar cell.
Context-dependent transcriptional interpretation of mitogen activated protein kinase signaling in the Drosophila embryo
Authors: Kim Yoosik , Iagovitina Antonina , Ishihara Keisuke , Fitzgerald Kate M. , Deplancke Bart , Papatsenko Dmitri , Shvartsman Stanislav Y.
Published: June 2013

Terminal regions of the Drosophila embryo are patterned by the localized activation of Mitogen Activated Protein Kinase (MAPK), which induces zygotic genes through relief of their repression by transcriptional repressor Capicua. The levels of MAPK activation at the anterior and posterior termini are close to each other, but the expression patterns of MAPK-target genes, such as zerknüllt (zen) and tailless (tll), display strong anterior-posterior (AP) asymmetry. This region-specific response to MAPK activation provides a clear example of context-dependent interpretation of inductive signaling, a common developmental effect that remains poorly understood. In the past, the AP asymmetry of zen expression was attributed to a mechanism that depends on MAPK substrate competition. We present data suggesting that the asymmetric expression of tll is generated by a different mechanism, based on feedforward control and multiple enhancers of the tll gene. A simple mathematical model of this mechanism correctly predicts how the wild-type expression pattern of tll changes in mutants affecting the anterior, dorsoventral, and terminal patterning systems and some of their direct targets.
On the non-randomness of maximum Lempel Ziv complexity sequences of finite size
Authors: Estevez-Rams E. , Lora Serrano R. , Aragón Fernández B. , Brito Reyes I.
Published: June 2013

Random sequences attain the highest entropy rate. The estimation of entropy rate for an ergodic source can be done using the Lempel Ziv complexity measure yet, the exact entropy rate value is only reached in the infinite limit. We prove that typical random sequences of finite length fall short of the maximum Lempel-Ziv complexity, contrary to common belief. We discuss that, for a finite length, maximum Lempel-Ziv sequences can be built from a well defined generating algorithm, which makes them of low Kolmogorov-Chaitin complexity, quite the opposite to randomness. It will be discussed that Lempel-Ziv measure is, in this sense, less general than Kolmogorov-Chaitin complexity, as it can be fooled by an intelligent enough agent. The latter will be shown to be the case for the binary expansion of certain irrational numbers. Maximum Lempel-Ziv sequences induce a normalization that gives good estimates of entropy rate for several sources, while keeping bounded values for all sequence length, making it an alternative to other normalization schemes in use.
Photoemission characteristics of (Cs, O) activation exponential-doping Ga0.37Al0.63As photocathodes
Authors: Chen Xinlong , Zhao Jing , Chang Benkang , Yu Xiaohua , Hao Guanghui , Xu Yuan , Cheng Hongchang
Published: June 2013

Based on the studies of the GaAs photocathode, the surface model of the Ga0.37Al0.63As photocathode is investigated and the energy distributions of electrons reaching the surface charge region, reaching the surface and emitting into vacuum are calculated. The (Cs, O) adsorption and photoemission characteristics of the Ga0.37Al0.63As photocathode are studied according to the experiments. We use the quantum efficiency formula to fit the experimental curve, and obtain the performance parameters of the photocathode and the surface barrier parameters. The results show that the surface barrier of the Ga0.37Al0.63As photocathode is similar to that of the GaAs photocathode. The prepared reflection-mode Ga0.37Al0.63As photocathode responds to the blue-green light, while the transmission-mode Ga0.37Al0.63As photocathode is sensitive to the 532 nm light.
Femtosecond laser ablation of brass in air and liquid media
Authors: Shaheen M. E. , Gagnon J. E. , Fryer B. J.
Published: June 2013

Laser ablation of brass in air, water, and ethanol was investigated using a femtosecond laser system operating at a wavelength of 785 nm and a pulse width less than 130 fs. Scanning electron and optical microscopy were used to study the efficiency and quality of laser ablation in the three ablation media at two different ablation modes. With a liquid layer thickness of 3 mm above the target, ablation rate was found to be higher in water and ethanol than in air. Ablation under water and ethanol showed cleaner surfaces and less debris re-deposition compared to ablation in air. In addition to spherical particles that are normally formed from re-solidified molten material, micro-scale particles with varying morphologies were observed scattered in the ablated structures (craters and grooves) when ablation was conducted under water. The presence of such particles indicates the presence of a non-thermal ablation mechanism that becomes more apparent when ablation is conducted under water.
Pre-ignition laser ablation of nanocomposite energetic materials
Authors: Stacy S. C. , Massad R. A. , Pantoya M. L.
Published: June 2013

Laser ignition of energetic material composites was studied for initiation with heating rates from 9.5 × 104 to 1.7 × 107 K/s. This is a unique heating rate regime for laser ignition studies because most studies employ either continuous wave CO2 lasers to provide thermal ignition or pulsed Nd:YAG lasers to provide shock ignition. In this study, aluminum (Al) and molybdenum trioxide (MoO3) nanoparticle powders were pressed into consolidated pellets and ignited using a Nd:YAG laser (1064 nm wavelength) with varied pulse energy. Results show reduced ignition delay times corresponding to laser powers at the ablation threshold for the sample. Heating rate and absorption coefficient were determined from an axisymmetric heat transfer model. The model estimates absorption coefficients from 0.1 to 0.15 for consolidated pellets of Al + MoO3 at 1064 nm wavelength. Ablation resulted from fracturing caused by a rapid increase in thermal stress and slowed ignition of the pellet.
Understanding polarization vs. charge dynamics effects in ferroelectric-carbon nanotube devices
Authors: Blaser Cédric , Esposito Vincent , Paruch Patrycja
Published: June 2013

To optimize the performance of multifunctional carbon nanotube-ferroelectric devices, it is necessary to understand both the polarization and charge dynamics effects on their transconductance. Directly comparing ferroelectric Pb(Zr0.2Ti0.8)O3 and dielectric SrTiO3 field effect transistors, we show that the two effects strongly compete, with transient charge dynamics initially masking up to 40% of the ferroelectric field effect. For applications, it is therefore crucial to maximize the quality of the ferroelectric film and the interface with the carbon nanotube to take full advantage of the switchable polarization.
Temperature-dependent exciton-related transition energies mediated by carrier concentrations in unintentionally Al-doped ZnO films
Authors: Tang Kun , Gu Shulin , Ye Jiandong , Huang Shimin , Gu Ran , Zhu Shunming , Zhang Rong , Shi Yi , Zheng Youdou
Published: June 2013

The authors reported on a carrier-concentration mediation of exciton-related radiative transition energies in Al-doped ZnO films utilizing temperature-dependent (TD) photoluminescence and TD Hall-effect characterizations. The transition energies of free and donor bound excitons consistently change with the measured TD carrier concentrations. Such a carrier-concentration mediation effect can be well described from the view of heavy-doping-induced free-carrier screening and band gap renormalization effects. This study gives an important development to the currently known optical properties of ZnO materials.
The Role of Planning in Delivering Low-Carbon Urban Infrastructure
Authors: Williams Joanna
Published: June 2013

Cities are the single largest contributor to climate change. Thus it is important that, where possible, low-carbon infrastructure is integrated into cities to try to reduce CO2 emissions. Planning (plans, policy, and process) can encourage this. In this paper international best practice is drawn upon to explore a range of planning approaches—collaborative, systemic, and market shaping—that have been used to introduce low-carbon infrastructure into cities. A new typology is developed and the strengths and weaknesses of planning approaches are evaluated. The importance of context in the success of each approach is highlighted and suggestions are made for the circumstances in which each may be most effectively employed, while exploring how planning can be used to provide a ‘protected space’ in which low-carbon systems can develop.
Driving the Agenda for Climate Change Adaptation in Norwegian Municipalities
Authors: Dannevig Halvor , Hovelsrud Grete K , Husabø Idun A
Published: June 2013

The absence of clear signals from the Norwegian state concerning climate change adaptation provides an opportunity to investigate why some municipalities have addressed adaptation to climate change while others have not. Although difficulties associated with implementing adaptation to climate change are well documented, less is known about those individuals who take the lead. On the basis of in-depth interviews and interaction with eight Norwegian municipalities that have begun working with climate adaptation, we examine how climate adaptation has been added to the local agenda. We find that adaptation planning has progressed more in those municipalities where officials are engaged and actively seeking external expertise and support. We conclude that, without a clearer national adaptation policy and greater resource allocation and legislation, adaptation to climate change within Norwegian municipalities is unlikely to progress further.
Functional welfare – using biochemical and molecular technologies to understand better the welfare state of peripartal dairy cattle
Authors: Loor J. J. , Bertoni G. , Hosseini A. , Roche J. R. , Trevisi E.
Published: June 2013

Animal welfare is an important social construct showing that humans recognise the sentient nature of animals and manage them accordingly; however, because the concept differs depending on individual perceptions of the acceptability of different practices and appropriate endpoint measurements, objective evaluation of an animal’s welfare state is challenging. A good level of welfare, however, is not achieved merely by the absence of difficulties (e.g. pain, injury, disease, distress) but by the animal’s capacity to overcome them. Production-oriented (utilitarian) opinions contend that high production indicates good welfare, as an animal must be healthy and well nourished to achieve it. Although there is truth in this premise, high production can, in itself, result in stresses, with no obvious signs that potentially predispose animals to ill health. The focus of the present paper is on peripartal dairy cattle as it relates to development of better measures for an objective evaluation of welfare state. Advances in high-throughput metabolite (metabolomics) and gene expression (transcriptomics) analysis techniques have enabled the rapid identification of multiple biomarkers that, in combination, reflect the metabolic and immunocompetence functional capacity of the animal. With this knowledge, the effects of management, nutrition, physiological state, and their interactions can be evaluated for their effect on functional capacity. As the links between metabolism, immunology (immunometabolism) and mental state are elucidated, these techniques also offer a means to assess whether the animal also experiences feelings of malaise. Collectively, these measurements, thus, can indicate ‘functional welfare’, which encompasses biological function, physical state, and some components of mental state as part of animal welfare.
Effect of Negative Ions on the Instability of Ion-acoustic Waves in a Relativistic Plasma
Authors: Mondal K. K. , Paul S. N. , Roychowdhury A.
Published: June 2013

The dispersion relation of an ion-acoustic wave propagating through a
collisionless, unmagnetised plasma, having warm isothermal electrons and cold
positive and negative ions has been derived. It is seen that the ion-acoustic
wave will be unstable in the presence of streaming of ions. Instability of the
wave is graphically analysed for the plasma having (H+,
O¯) ions, (H+, O2¯)
ions, (H+, SF5¯) ions,
(He+, Cl¯) ions and (Ar+,
O¯) ions with different negative ion concentration and relativistic
velocity.
Neutron and X-ray Reflectometry: Solid Multilayers and Crumpling Films
Authors: White John W. , Brown Anthony S. , Holt Stephen A. , Saville Paul M.
Published: June 2013

The structures of films and interfaces at the molecular level can be
determined from specular reflectivity measurements using neutrons and X-rays.
A general introduction to the principles of neutron and X-ray reflectometry is
given. Illustrative examples of the application of neutron and X-ray
reflectometry to problems of chemical and physical interest are presented.
Meson Spectrum from the Bethe-Salpeter Equation
Authors: Burden C. J. , Qian L. , Roberts C. D. , Tandy P. C. , Thomson M. J.
Published: June 2013

We present details of a model for calculating the mass spectrum of light-quark
mesons and decay constants of the pseudoscalar meson octet from a
phenomenological model based on Dyson–Schwinger and Bethe–Salpeter
equations. In this model the Bethe-Salpeter kernel is approximated by a
separable ansatz obtained from input quark propagators.
Spin Structure Functions of the Nucleon and Twist-3 Operators in QCD
Authors: Tanaka Kazuhiro
Published: June 2013

We investigate the twist-3 spin-dependent parton distribution functions
hL(x;
Q2) and
gT (x;
Q2). We discuss the physical
relevance of the parton distributions from the view point of the factorization
theorem in QCD. A unique feature of the ‘measurable’ higher-twist
distributions hL and
gT is emphasized. We investigate
the Q2 -evolution of
hL and
gT in the framework of the
renormalization group and standard QCD perturbation theory. We calculate the
anomalous dimension matrix for the twist-3 operators for
hL and
gT in the one-loop order. The
operator mixing among the relevant twist-3 operators, including the operators
proportional to the QCD equations of motion, is treated properly in a
consistent scheme. Implications for future experiments are also discussed.
Finite-Size Scaling and Effective Lagrangian Theory
Authors: Hamer C. J.
Published: June 2013

A brief review is given of the ‘effective Lagrangian’ approach of
Leutwyler, Hasenfratz and others, which describes the behaviour at low
energies or temperatures, or large distances, in lattice systems which undergo
a first-order transition involving spontaneous breakdown of a continuous
symmetry. Universal predictions can be given, based on a continuum field
theory of the massless Goldstone bosons generated by the breakdown of the
symmetry, which control the behaviour in these regimes. In particular, the
finite-size scaling behaviour can be predicted, in a way very similar to the
predictions of conformal invariance for a two-dimensional system at a critical
point. Conversely, measurements of the finite-size scaling behaviour can give
estimates of the parameters of the Goldstone bosons. These points are
illustrated using data for the O(2) Heisenberg spin model in (2+1)
dimensions, and the XXZ antiferromagnet on a square lattice.
Gauge Invariant Magnetism
Authors: Stewart A. M.
Published: June 2013

An introduction is given to features of gauge invariance in classical and
quantum mechanics that are of importance for magnetism in condensed matter
systems. A version of quantum mechanics is described in which full
electromagnetic gauge arbitrariness is displayed explicitly at every stage.
The division of orbital magnetism into paramagnetism and diamagnetism is
examined and it is shown that only by treating both of these on an equal
footing can a gauge invariant treatment of magnetism be constructed.
Phase Transitions and Molecular Reorientations in Bilayered n-Heptadecylammonium Chloride
Authors: Reynhardt E. C.
Published: June 2013

An investigation of phase transitions and molecular motions in polycrystalline
n-heptadecylam- monium chloride
(C17H35NH3Cl),
employing differential scanning calorimetry, x-ray powder diffraction and
nuclear magnetic resonance techniques, is reported. This compound can occur in
two virgin polymorphs at room temperature, one interdigitated and one
noninterdigitated. The temperature at which crystallisation occurs determines
the polymorph that forms. If these polymorphs are heated transitions to
noninterdigitated γ, β and α phases occur. Cooling to room
temperature shows the same phase transitions, but the virgin phase is not
formed. Instead, a noninterdigitated .epsi; phase is formed. Defect motions
of chain-ends play a significant role in the spin-lattice relaxation rates in
all the phases. In the α phase a degree of chain melting is present. The
molecular dynamics of chains differs during heating and cooling cycles in the
.epsi; phase. If the temperature is kept constant during a heating cycle in
this phase, fourfold motions of chains are frozen over a period of several
hours, but the sample remains noninterdigitated. It seems that the
interdigitation process is hampered by the population of defect orientations
of chain-ends. The methyl group executes classical threefold reorientations
and the NH3 group jumps in an asymmetric threefold
potential well.
Twinkle, Twinkle Little Pulsar/Quasar
Authors: Melrose D. B.
Published: June 2013

The twinkling of stars is a familiar example of scintillations, due to
turbulence in the Earth’s atmosphere causing fluctuations in the
refractive index of the air along the line of sight. Scintillations lead to
time variations in the apparent position of the source, and hence to an
angular broadening on integration over an observation time. Scintillations
also lead to fluctuations in the intensity of the source. Pointlike
astronomical radio sources such as pulsars and (the compact cores of some)
quasars scintillate due to fluctuations in the electron density along the line
of sight through the interstellar medium. For quasars, low-frequency (100s of
MHz) variability over periods of years is a scintillation effect, as are
probably more rapid (as short as an hour) intensity variations at higher radio
frequencies. Unlike the twinkling of stars, which is due to weak
scintillations, the scintillations of radio sources are usually strong.
Important qualitative effects associated with strong scattering are multipath
propagation and a clear separation into diffractive and refractive
scintillations. Quasars exhibit only refractive scintillations. Pulsars are
extremely small and bright, and they vary temporally on a very short time
scale, making them almost ideal sources on which to test our ideas on
scintillations.
Pulsars exhibit a variety of scintillation phenomena, due to both refractive
and diffractive effects, the latter seen most clearly in dynamic spectra.
These data are used to model the distribution of electrons through the Galaxy,
to determine the distribution of pulsar velocities, and potentially to resolve
the source region in a pulsar magnetosphere.
These scintillation phenomena and their interpretation in terms of the theory
of strong scintillations are reviewed briefly. The generalisation of the
theory to include the birefringence of the plasma (Faraday effect), and its
possible implications on the interpretation of circular polarisation, are then
outlined. An attempt to generalise the theory to describe scattering by a
distribution of discrete scattering objects is also discussed briefly.
Analyses of Inelastic Proton Scattering to High Spin States of Unnatural Parity
Authors: Amos K , Morton J , Morrison I , Smith R
Published: June 2013

Distorted wave approximation analyses of 135 MeV inelastic proton scattering to high spin (4 - and 6-) unnatural parity states in 24Mg and 28Si have been made to test the character of an effective two-nucleon interaction, assuming a transition spectroscopy of particle-hole excitation from a projected Hartree-Fock intrinsic ground state.
The Motion of Spinless Particles in General Relativity
Authors: Gregory LJ , Klotz AH
Published: June 2013

A technique is developed, which uses a general energy-momentum tensor, to derive the equations of motion in general relativity. This enables the geodesic equations for spinless particles to be deduced.
Nonstatic Spherically Symmetric Isotropic Solutions for a Perfect Fluid in General Relativity
Authors: Wyman Max
Published: June 2013

The present author (Wyman 1946) showed that all perfect fluids which can be represented by nonstatic, spherically symmetric, isotropic solutions of the Einstein field equations can be found by solving a nonlinear total differential equation of the second order involving. an arbitrary function 'P(r). Since then several particular solutions of this equation have been found. Although the four solutions given recently by Chakravarty et at. (1976) involve particular choices of 'P(r), none of these is the general solution of the equation that results from the specific choice of 'P(r) that was made. The present paper shows how these four general solutions are obtained.
Remark on the Polytrope of Index 5
Authors: Buchdahl HA
Published: June 2013

Contrary to statements in the current literature the gravitational potential energy of the poly trope of index 5 is finite; With e. denoting the least positive zero of the Emden function of index n, the value of the limit as n -4 5 of (5 - n)e. is determined and made the basis of a simple rational approximation to e. qua function of n.
Calculation of 6j Symbols for the Exceptional Group E7
Authors: Butler PH , Haase RW , Wybourne BG
Published: June 2013

The 6j symbols of the exceptional group �7 are studied and evaluated explicitly for a number of important cases involving the fundamental and adjoint representations. These 6j symbols suffice to calculate all the 3jm factors (or isoscalar factors) involving the fundamental or adjoint representations of �7 at least twice, except in the latter case those involving the power-4 irreps (426) and (3 225).
Thermal Instability of a Partially Ionized Plasma
Authors: Sharma RC , Sharma KC
Published: June 2013

A study is made of the thermal hydromagnetic instability of a rotating and finitely conducting composite medium, including frictional effects with neutrals. The prevalent magnetic field is assumed to be uniform and vertical. The effects of the magnetic field and rotation are found to be stabilizing on the thermal instability of such a composite medium. The case of a partially ionized medium is also considered, including the effect of Hall currents in the presence of a uniform vertical magnetic field. For stationary convection, the collisions have no effect while the Hall currents are found to have a destabilizing effect on the thermal instability.
Dirac Particles in the Minkowski Space with Torsion
Authors: O'Connor MP , Smrz PK
Published: June 2013

After presenting a simple derivation of the covariant derivative of the Dirac spinor functions, the Dirac equation in the space of constant torsion, Minkowski metric and straight line geodesics is considered. Solutions of the equation are given, showing the particular way in which the energy degeneracy of the states with different spin projections is removed in the presence of torsion.
Analysis Using Ion Induced g Rays
Authors: Bird JR , Scott MD , Russell LH , Kenny MJ
Published: June 2013

Gamma ray energies and some thick sample reaction yields are summarized for proton, deuteron, triton, 3He and IX-particle induced )' rays which have been used in prompt nuclear analysis work.
The Axially Symmetric Stationary Vacuum Field Equations in Einstein's Theory of General Relativity
Authors: Sloane A
Published: June 2013

All formulations of Einstein's vacuum field equations for which exact solutions have been found in the axially symmetric stationary case are compared, and the inherent restrictions of each are displayed. A measure of their usefulness as theoretical tools is gained by the ease with which they admit Kerr's (1963) solution (it being the simplest asymptotically flat metric of this kind). The solutions found using each formulation are listed and, where possible, suitably classified.
Effect of Solar Modulation on the Low Energy Sea Level Muon Spectrum Near the Geomagnetic Equator
Authors: Bhattacharyya DP
Published: June 2013

A study is made of the influence of long-term solar modulation on the low energy sea level muon spectrum near the geomagnetic equator. Recent experimental data are compared with theoretical results calculated from the phenomenological model of Allkofer and Dau. It is suggested that the observed enhancement in the muon intensity is mainly due to a shift in the solar potential.
Photoneutron Cross Section of 54 Fe
Authors: Norbury JW , Thompson MN , Shoda K , Tsubota H
Published: June 2013

A high resolution measurement of the 54Pe(y, n) cross section is reported. This and a previously measured 54Pe(y, p) cross section are discussed in terms of the isospin splitting of the El giant dipole.
Nature of Circinus X-1
Authors: Haynes RF , L Jauncey David , Lerche I , Murdin PG
Published: June 2013

X-ray, radio and optical observations have been used to derive a binary star model for CircinusX-1. Mass transfer between the primary star (Mp ~ 20Mo) and the compact companion star (Me ~ Mo) triggers one or more expanding shock fronts in the vicinity of the compact star. These shocks produce the observed radio emission. Variable optical emission arises both from the changing Roche lobe surface in the highly eccentric system (e ~ 0�8) and from degradation of shock-produced X-ray photons to the optical band by material overlying the expanding shock. The X-ray radiation results from matter in the accretion disc dribbling down on to the surface of the compact star. Mass replenishment at a rate of 5 x 10-8 to 5 X 10-10 Mo per orbit (16�6 day period) occurs near periastron passage. The variation of the X-ray emission arises from absorption in the stellar wind of the primary star. The model predicts an apsidal rotation period for the elliptical orbit of 7-400 yr, an orbital circularization time of ~ 500 yr and a period change of about 0�5 day per 10 yr.
A New Catalogue of Galactic SNRs Corrected for Distance from the Galactic Plane
Authors: Milne DK
Published: June 2013

A new catalogue of 125 galactic SNRs is presented. A surface brightness-diameter relationship, corrected for variation in height I z I above the galactic plane, is derived and applied to the catalogue to yield I z I-corrected distances and diameters. A birth rate of about one every 30 or 40 years is indicated from the number-diameter diagram.
An Investigation of the Accuracy of Numerical Solutions of Boltzmann's Equation for Electron Swarms in Gases with Large Inelastic Cross Sections
Authors: D Reid Ivan
Published: June 2013

A Monte Carlo simulation technique has been used to test the accuracy of electron energy distribution functions and transport coefficients calculated using conventional numerical solutions of Boltzmann's equation based on a two-term approximation. The tests have been applied to a number of model gases, some of which have characteristics close to those of real gases, and include cases where the scattering is anisotropic. The results show that, in general, previous application of the numerical solution to real gases has been valid.
Models of Radio Recombination Line Sources
Authors: Batty MJ
Published: June 2013

Models for the southern HII regions RCW38, RCW49, the Carina Nebula, G305+0 and M17 are constructed using a range of line and continuum data. Electron temperatures in the range 5000-7300 K are derived from the analysis, and in most cases these are consistent with estimates obtained from radio continuum measurements. The presence of a low temperature (.;; 4000 K) outer region in RCW 38 is suggested by the low frequency line data. Density inhomogeneities are found to be significant in all sources, while the predicted line widths are consistent with an observed lack of collisional broadening at low frequencies.
Atmospheric Gravity Wave Production for the Australian Total Solar Eclipse of 23 October 1976
Authors: Ball SM
Published: June 2013

Calculations are presented which suggest that internal gravity waves generated by the 23 October 1976 total solar eclipse would have come to a focus in a region well north of Australia, and also in Antarctica. No evidence is found for a focus in Western Australia, as suggested by Beer et al. (1976).
Dynamic Deformation Theory and Multiphonon Vibrational Bands in 154Gd
Authors: Kumar K , Gupta JB , Hamilton JH
Published: June 2013

Dynamic deformation theory based on a pairing plus quadrupole model (DPPQ model) is extended to 25 levels belonging to various multi phonon vibrational bands in 154Gd. Although the calculated excited band energies are too high by factors of 1�4-1�7, there is generally reasonable agreement with the experimental energies, B(E2) values, magnetic moments, E2-Ml mixing ratios and EO moments. Many new values are predicted. A brief comparison with some results derived from a new version of dynamic deformation theory, the so-called DNSB model, is also given.