bluuebunny/crossref_metadata_2025 huggingface dataset:
Spontaneous formation of travelling localized structures and their asymptotic behaviour in binary fluid convection
Authors: Watanabe Takeshi , Iima Makoto , Nishiura Yasumasa
Published: September 2012

We study spontaneous pattern formation and its asymptotic behaviour in binary fluid flow driven by a temperature gradient. When the conductive state is unstable and the size of the domain is large enough, finitely many spatially localized time-periodic travelling pulses (PTPs), each containing a certain number of convection cells, are generated spontaneously in the conductive state and are finally arranged at non-uniform intervals while moving in the same direction. We found that the role of PTP solutions and their strong interactions (collision) are important in characterizing the asymptotic state. Detailed investigations of pulse–pulse interactions showed the differences in asymptotic behaviour between that in a finite but large domain and in an infinite domain.
Ageostrophic instability in rotating shallow water
Authors: Wang Peng , McWilliams James C. , Kizner Ziv
Published: September 2012

Linear instabilities, both momentum-balanced and unbalanced, in several different $ \overline{u} (y)$ shear profiles are investigated in the rotating shallow water equations. The unbalanced instabilities are strongly ageostrophic and involve inertia–gravity wave motions, occurring only for finite Rossby ($\mathit{Ro}$) and Froude ($\mathit{Fr}$) numbers. They serve as a possible route for the breakdown of balance in a rotating shallow water system, which leads the energy to cascade towards small scales. Unlike previous work, this paper focuses on general shear flows with non-uniform potential vorticity, and without side or equatorial boundaries or vanishing layer depth (frontal outcropping). As well as classical shear instability among balanced shear wave modes (i.e. B–B type), two types of ageostrophic instability (B–G and G–G) are found. The B–G instability has attributes of both a balanced shear wave mode and an inertia–gravity wave mode. The G–G instability occurs as a sharp resonance between two inertia–gravity wave modes. The criterion for the occurrence of the ageostrophic instability is associated with the second stability condition of Ripa (1983), which requires a sufficiently large local Froude number. When $\mathit{Ro}$ and especially $\mathit{Fr}$ increase, the balanced instability is suppressed, while the ageostrophic instabilities are enhanced. The profile of the mean flow also affects the strength of the balanced and ageostrophic instabilities.
Mini Nutritional Assessment predicts gait status and mortality 6 months after hip fracture
Authors: Gumieiro David N. , Rafacho Bruna P. M. , Gonçalves Andrea F. , Tanni Suzana E. , Azevedo Paula S. , Sakane Daniel T. , Carneiro Carlos A. S. , Gaspardo David , Zornoff Leonardo A. M. , Pereira Gilberto J. C. , Paiva Sergio A. R. , Minicucci Marcos F.
Published: September 2012

The aim of the present study was to evaluate the Mini Nutritional Assessment (MNA), the Nutritional Risk Screening (NRS) 2002 and the American Society of Anesthesiologists Physical Status Score (ASA) as predictors of gait status and mortality 6 months after hip fracture. A total of eighty-eight consecutive patients over the age of 65 years with hip fracture admitted to an orthopaedic unit were prospectively evaluated. Within the first 72 h of admission, each patient's characteristics were recorded, and the MNA, the NRS 2002 and the ASA were performed. Gait status and mortality were evaluated 6 months after hip fracture. Of the total patients, two were excluded because of pathological fractures. The remaining eighty-six patients (aged 80·2 (sd 7·3) years) were studied. Among these patients 76·7 % were female, 69·8 % walked with or without support and 12·8 % died 6 months after the fracture. In a multivariate analysis, only the MNA was associated with gait status 6 months after hip fracture (OR 0·773, 95 % CI 0·663, 0·901; P= 0·001). In the Cox regression model, only the MNA was associated with mortality 6 months after hip fracture (hazard ratio 0·869, 95 % CI 0·757, 0·998; P= 0·04). In conclusion, the MNA best predicts gait status and mortality 6 months after hip fracture. These results suggest that the MNA should be included in the clinical stratification of patients with hip fracture to identify and treat malnutrition in order to improve the outcomes.
Emotional Disagreement: The Role of Semantic Content in the Expression of, and Disagreement Over, Emotional Values
Authors: STOJANOVIC ISIDORA
Published: September 2012

ABSTRACT: When we describe an event as sad or happy, we attribute to it a certainemotional value. Attributions of emotional value depend essentially on an agent (and on his or her emotional responses); and yet, people readily disagree over such values. My aim in this paper is to explain what happens in the case of “emotional disagreement”, and, more generally, to provide some insight into the semantics of value-attributions.
From Content-Externalism to Vehicle-Externalism
Authors: L’hote Crystal
Published: September 2012

ABSTRACT: Consensus has it that Putnam-Burge style arguments for content-externalism do not strengthen the case for vehicle-externalism, i.e., the thesis that some mental states include as their parts notebooks, iPhones, and other extra-bodily phenomena. Rowlands and Sprevak, among others, argue that vehicle-externalism gets stronger support from Clark and Chalmers’s parity principle and functionalism, generally. I contest this assessment and thereby give reason to reconsider the support that content-externalism provides the extended mind thesis: although content-externalism does not entail vehicle-externalism, as Rowlands argues, neither does functionalism. The functionalist cannot reject the content-externalist argument for vehicle-externalism on these grounds without undercutting her own.
Physical-Effect Epiphenomenalism and Common Underlying Causes
Authors: MOORE DWAYNE
Published: September 2012

Qualia epiphenomenalism is the view that qualitative properties of events, such as the raw feel of tastes or painfulness, lack causal efficacy. One common objection to qualia epiphenomenalism is the epistemic argument, which states that this loss of causal efficacy undermines our capacity to know about these epiphenomenal qualitative properties (Sterjnberg, 1999; Watkins, 1989). A number of rejoinders have been offered up to insulate qualia epiphenomenalism from the epistemic argument. In this paper I consider and ultimately reject two such replies, namely, the common underlying cause reply and the appeal to physical-effect epiphenomenalism.
Intra-Family Inequality and Justice
Authors: LANDES XAVIER , NIELSEN MORTEN EBBE JUUL
Published: September 2012

In “The Pecking Order,” Dalton Conley argues that inequalities between siblings are larger than inequalities at the level of the overall society. Our article discusses the normative implications for institutions of this observation. We show that the question of state intervention for curbing intra-family inequality reveals an internal tension within liberalism between autonomy and toleration, which bears on the forms that the intervention of institutions may take. Despite the pros and cons of both commitments, autonomy-based liberalism appears more compatible with the involvement of the state for egalitarian reasons within the family than toleration-based liberalism.
THE WATER RELATIONS AND IRRIGATION REQUIREMENTS OF MACADAMIA (MACADAMIA SPP.): A REVIEW
Authors: CARR M. K. V.
Published: September 2012

The macadamia nut is the only commercial food crop indigenous to Australia. It originated along the fringes of rainforests, only becoming an important internationally traded crop in the late 20th century. Australia is now the main centre of production, following a lead set by Hawai'i. The crop is also important in Central America and southern Africa. The majority of recent research reported in the literature on the physiology and water relations of macadamia has been undertaken in Australia. Macadamia is a tall evergreen tree in which vegetative growth occurs in a series of flushes. Mild water stress suppresses growth, but compensatory growth occurs on re-watering. Flowers form on hardened wood within the leaf canopy. Floral initiation occurs in late autumn, with flowering in the following spring. Flowering is profuse but only 5–10% of the flowers set fruit and less than 1% of the flowers reach maturity as fruits due largely to premature abscission. High temperatures (>30 °C) can contribute to the shedding of fruit. It takes about 12 months from floral initiation to the completion of harvest. Macadamia root systems are described as relatively shallow and spreading. The taproot can extend to depths of >1.2 m, with a dense matt of fibrous roots in the top 0.4 m. Proteoid rootlets are also present. Stomata are only found on the abaxial surface of the leaf. Macadamia has several attributes that help to explain its apparent tolerance to periodic dry conditions as found in its native habitat. These include leaves with xeromorphic adaptations, stomatal closure without concurrent changes in leaf water potential and an efficient water transport system. There has only been one serious attempt to measure the actual water use of macadamia. Most irrigation experiments have been poorly planned and/or the outcomes were inconclusive. Nut yields are cyclical and highly variable, making it difficult to establish cause and effect. It is not yet possible to say with evidence where and when irrigation is worthwhile.
CLUBFEET AND KYPSELIDS: CONTEXTUALISING CORINTHIAN PADDED DANCERS IN THE ARCHAIC PERIOD
Authors: Ziskowski Angela
Published: October 2012

The significance behind the imagery of the padded dancer, orkomast, traditionally has been connected to early drama, Dionysos, or ritual practices. Most Archaic Corinthian vases that include these figures portray them dancing, and a percentage of those dancers also illustrate a deformity of the foot. This article attempts to contextualise the clubfooted padded dancer within its political, cultural and geographic boundaries by offering an explanation for the end of production of these figures in Corinth. The lame padded dancer may have been a localised symbol offering political commentary on historical traditions of lameness within the tyrannical family of Corinth. Its production and discontinuation may be connected to the rise and fall of this family.
Is use of formal community services by older women related to changes in their informal care arrangements?
Authors: MCKENZIE SAMANTHA J. , LUCKE JAYNE C. , HOCKEY RICHARD L. , DOBSON ANNETTE J. , TOOTH LEIGH R.
Published: September 2012

This paper examines how the relationships between the factors (predisposing, enabling and illness) of the 1973 Andersen framework and service use are influenced by changes in the caring role in older women of the 1921–26 cohort of the Australian Longitudinal Study on Women's Health. Outcome variables were the use of three formal community support services: (a) nursing or community health services, (b) home-making services and (c) home maintenance services. Predictor variables were survey wave and the following carer characteristics: level of education, country of birth, age, area of residence, ability to manage on income, need for care, sleep difficulty and changes in caring role. Carer changes were a significant predictor of formal service use. Their inclusion did not attenuate the relationship between the Andersen framework factors and service use, but instead provided a more complete representation of carers' situations. Women were more likely to have used support services if they had changed into or out of co-resident caring or continued to provide co-resident care for a frail, ill or disabled person, needed care themselves, and reported sleep difficulties compared with women who did not provide care. These findings are important because they indicate that support services are particularly relevant to women who are changing their caring role and who are themselves in need of care.
Evaluating authorship distance methods using the positive Silhouette coefficient
Authors: LAYTON ROBERT , WATTERS PAUL , DAZELEY RICHARD
Published: September 2012

Unsupervised Authorship Analysis (UAA) aims to cluster documents by authorship without knowing the authorship of any documents. An important factor in UAA is the method for calculating the distance between documents. This choice of the authorship distance method is considered more critical to the end result than the choice of cluster analysis algorithm. One method for measuring the correlation between a distance metric and a labelling (such as class values or clusters) is the Silhouette Coefficient (SC). The SC can be leveraged by measuring the correlation between the authorship distance method and the true authorship, evaluating the quality of the distance method. However, we show that the SC can be severely affected by outliers. To address this issue, we introduce the Positive Silhouette Coefficient, given as the proportion of instances with a positive SC value. This metric is not easily altered by outliers and produces a more robust metric. A large number of authorship distance methods are then compared using the PSC, and the findings are presented. This research provides an insight into the efficacy of methods for UAA and presents a framework for testing authorship distance methods.
The Fear of Others: A Pilot Study of Social Anxiety Processes in Paranoia
Authors: Newman Taylor Katherine , Stopa Luisa
Published: September 2012

Background and Aims:There is good reason to consider the role of social anxiety processes in paranoia; both the research and clinical literature indicate significant overlap between the two presentations. The aim of this study was to explore cognition and behaviour that are typically associated with social phobia, in people with paranoia, and then to draw out theoretical and clinical implications.Method:We used a cross-sectional between-subjects design to compare participants with persecutory delusions (without social phobia), social phobia, a clinical control group with panic disorder, and a non-clinical control group. Ten to 15 people were recruited to each of four groups, with a final total of 48 participants. Each person completed measures of automatic thoughts, underlying assumptions, core beliefs and behaviour, and took part in a semi-structured interview designed to assess process (self-consciousness and attentional focus) and metacognitive beliefs.Results:Surprisingly, measures of cognition and behaviour yielded no systematic differences between people with persecutory delusions and social phobia.Conclusions:People with persecutory delusions may experience overt and underlying cognition typically associated with social phobia, and behave in similar ways in response to perceived social threat. These initial results indicate: (i) that larger scale research is now warranted in order to draw firm conclusions about social anxiety processes in paranoia; (ii) more specific hypotheses to be tested; and (iii) a clinical model of paranoia, based on the cognitive model of social phobia, which might now usefully be validated.
Agoraphobia: An Outreach Treatment Programme
Authors: Croft Alison , Hackmann Ann
Published: September 2012

Background: Agoraphobia is disabling and clients find it hard to access effective treatment. Aims: This paper describes the development of an inexpensive service, delivered by trained volunteers in or near the client's own home. Method: We describe the development of the service, including selection, training and supervision. Outcomes were evaluated over 5 years, and compared with those available from the local psychology service. Results: Effect sizes on all measures were high. Benchmarking indicated that results on comparable measures were not significantly different from the local psychology service. As in many previous studies drop-out rate was fairly high. Conclusions: This model worked well, and was inexpensive and effective. Further research on long term outcome and methods of enhancing engagement is needed.
A QUANTITATIVE ANALYSIS OF TAX ENFORCEMENT AND OPTIMAL MONETARY POLICY
Authors: Arbex Marcelo
Published: September 2012

This paper explores the consequences of tax enforcement policies for monetary policy. Agents may evade taxes by working in the informal sector, but they are detected with positive probability. Workers are rewarded with government benefits that are proportional to formal (taxed) work. When enforcement is imperfect and collecting taxes is costly, the optimal inflation rate is positive and inflation becomes a second-best tax. Deviations from the Friedman rule are optimal and depend on the tax enforcement policies. Using U.S. data, we compute the quantitative effect of different tax structures on inflation and interest rate. We show that different tax enforcement and government spending (benefits) policies induce different optimal outcomes for inflation and interest rates.
CREDIT FRICTIONS AND FIRM DYNAMICS
Authors: Zeng Zheng
Published: September 2012

In this paper I develop a dynamic stochastic general equilibrium model of credit frictions in which the production technology provides a U-shaped average cost curve, enabling endogenous solutions for firm size and quantity. Firms weigh the present value of future net revenues against the opportunity cost of staying in business in their entry or exit decisions. I find that credit frictions increase variable investment costs and result in a larger firm size and a smaller number of firms in the steady state. As the economy deviates from the steady state, however, the presence of credit frictions increases fluctuation in the number of firms, raising market entry during an economic upturn and market exit during a downturn. Also, I find that allowing free entry mitigates some of the effects of credit frictions due to macroeconomic fluctuations. In addition to the homogeneous-firm model, I examine the model when firms have heterogeneous access to credit and find that different credit access gives rise to different firm sizes in the steady state. Firms with easier access to credit become larger than those with less access to credit. Heterogeneous credit access also means that these two types of firms will respond differently to a common technology shock.
DEMOGRAPHY AND GROWTH: A UNIFIED TREATMENT OF OVERLAPPING GENERATIONS
Authors: Bruce Neil , Turnovsky Stephen J.
Published: September 2012

We construct a unified overlapping-generations framework of equilibrium growth that includes the Blanchard “perpetual youth” model, the Samuelson model, and the infinitely lived–agent model as limit specifications for a “realistic” two-parameter survivorship function. We assess how the limit specifications compare with the general survival function, and analyze how exogenous changes in demographic conditions affect equilibrium growth and savings rates. Predicted effects are consistent with some cross-country correlations between demographic conditions and growth rates.
Histological and Immunohistochemical Study on Iberian Red Deer (Cervus elaphus hispanicus) Haemal Nodes
Authors: Guerrero F. , Cerutti P. , Marcaccini A. , García A.
Published: September 2012

Haemal nodes are capsulated, lymphoid organs with haemal circulation. Their parenchyma is distributed in primary and secondary lymphatic nodes in the cortical and medullar zones. In these zones the lymphatic tissue may adopt a cord-like shape and it is composed by plasma cell, macrophages and B and T lymphocytes. Blood circulates through the sinuses situated underneath the capsule, around the trabeculae and in the marrow.
Characterization of Salivary Calculi
Authors: Nolasco P. , Anjos A. J. , Almeida A. , Marques J. M. Aquino , Cabrita F. , da Costa E. Carreira , Mendes J. Rocha , de Matos A. P. Alves , Carvalho P. A.
Published: September 2012

Calculi in salivary glands and ducts (sialoliths) can be found in about 1% of the general population. Typically sialolithiasis causes long-term obstruction of salivary secretions, leading to atrophy of the gland with concomitant ceasing of the secretory function and ultimately fibrosis. Although some theories have been put forward regarding the etiology and pathogenesis of salivary calculi, the exact nucleation and growth mechanisms remain elusive. An exhaustive characterization of salivary calculi and systematic evaluation of the existing etiologic theories is therefore required.
Loss of Aggressiveness of Phytophthora cinnamomi (Beta-Cinnamomin Silenced Strain) in the Infection of Castanea sativa
Authors: Maia I. , Horta M. , Cravador A. , Medeira C.
Published: September 2012

Several forest species are severely affected by Phytophthora cinnamomi. The contribution of this oomycete to forest decline and dieback has been broadly reported. In particular, it is consensual that it is the causal agent of ink disease in Castanea sativa. It has been associated with the severe decline of Quercus species, namely the Q. suber and Q. ilex dieback in Portugal and Spain, and has been responsible for the infection of numerous native species and crops. This pathogen persists in the soil or on plant material in the form of chlamydospores allowing the infection of living root tissues when environmental conditions are favorable.
Peroxisomal Localization of CuZn Superoxide Dismutase in the Male Reproductive Tissues of the Olive Tree
Authors: Zafra A. , Jiménez-Quesada M. J. , Traverso J. A. , Corpas F. J. , Rodríguez-García M. I. , Alché J. D.
Published: September 2012

Superoxide dismutases (SODs) are a class of antioxidant enzymes which catalyze the dismutation of superoxide into oxygen and hydrogen peroxide, therefore controlling cellular levels of Reactive Oxygen Species (ROS). In the mature pollen grains of the olive tree, the presence of several forms of CuZn-SOD and the cytosolic localization of the enzyme have been described. The present study was aimed to elucidate the adaptation of the oxidative metabolism to the changing conditions occurring during the course of olive pollen formation, hydration and pollen tube emergence and growth. We used a polyclonal antibody (raised against a KLH-linked synthetic peptide including a consensus sequence for CuZn-SODs in olive pollen) in immunocytochemical experiments carried out by Fluorescence (FM) and Transmission Electron Microcopy (TEM).
APP Phosphorylation at S655 Correlates with F-actin Cytoskeleton Dynamics—Relevance in Neuronal Differentiation
Authors: Rocha J. F. , Vieira S. I. , Silva O. A. B. da Cruz e
Published: September 2012

The Alzheimer’s Amyloid Precursor Protein (APP) is a type 1 transmembranar protein that has been implicated in roles such as cell adherence, survival, migration and differentiation. Although a role in neuritogenesis has been attributed to APP, some contradictory results have been reported regarding the benefits of knocking-down or overexpressing APP. Our preliminary work indicated that pAPP (APP phosphorylated at the S655 residue) may potentially modulate APP-mediated neuronal differentiation, through mechanisms that may involve increased APP trafficking and cleavage, and altered APP-mediated cytoskeleton rearrangements. In order to address the ability of APP and pAPP to mediate neuronal differentiation, we used APP cDNA constructs fused to the Green Fluorescent Protein (GFP): wild-type APP and APP S655 mutants (S655A dephosphomimicking and S655E phosphomimicking mutants). SH-SY5Y neuroblastoma cells, a well documented neuronal-like cell model, were used, and the conditions for their retinoic-acid mediated differentiation and concomitant APP-GFP transfection were first optimized.
Long and Short Ordering in Cationic Deficient Manganese Related Brownmillerites
Authors: Ruiz-Gonzalez L. , Cortes-Gil R. , Alonso J. M. , Gonzalez-Calbet J. M.
Published: September 2012

Ever since colossal magnetoresistance (CMR) was discovered in Ln1-xAExMnO3 (Ln=lantanide; AE alkaline-earth), establishing the relationship between structure and properties constitutes a prominent place in the landscape of solid-state science because of its intriguing potential applications. The occurrence of different Mn3+/Mn4+ ratios seems to be responsible of the different magnetic behaviours observed and can be tuned by either changing i) the Ln/AE ratio or ii) the oxygen content, i.e., Ln1-xAExMnO3-δ. Although plenty of works has been devoted to the first point, less effort has been devoted to study the effect of the compositional variations at the oxygen sublattice. In spite of the partial break-up occurring at the 3D network of octahedral sharing corners, responsible of the double exchange interactions the oxygen deficient compounds exhibits complex magnetic and electric properties.
Nanodiamond Dispersions in Nanostructured Metals
Authors: Nunes D. , Correia J. B. , Carvalho P. A.
Published: September 2012

A microstructure refined to the nanometer scale originates mechanical property improvements [1]. However ultra-fine grain metals present low thermal stability, requiring the presence of particle dispersions to delay coarsening by grain boundary pinning. Nanoscale dispersions of diamond or graphite offer therefore thermal stability potential, combined with high hardness and thermal conductivity for diamond, and self-lubricating properties in the case of graphite. Copper-diamond (Cu-nD) and copper-graphite (Cu-G), nickel-diamond (Ni-nD) and nickel-graphite (Ni-G), as well as tungsten-diamond (W-nD) and tungsten-graphite (W-G) nanostructured composites have been produced by mechanical synthesis and subsequent heat-treatments. Fundamental challenges involve bonding carbon phases to the chosen matrices: copper exhibits an intrinsically difficult bonding with carbon; while tungsten is a strong carbide former; with Ni exhibiting intermediate characteristics. In addition, carbon phases are prone to amorphization by high-energy milling. Transmission electron microscopy (TEM) observations showed homogeneous particle distributions and intimate bonding between the metallic matrix and the carbon phases. Ring diffraction patterns of the chemically extracted carbon phases demonstrated that nanodiamond milled with Cu preserved crystallinity (Figure 1), while an essentially amorphous nature could be inferred for graphite. Systematic variation of the processing parameters enabled to minimize carbide formation with Ni and W matrices. Heat-treatment of the nanostructured of Ni-nD composites induced the transformation of nanodiamond into onion-like carbons (OLC) inside the Ni nanostructured matrix (Figure 2). Hardening mechanisms and the load transfer ability to the reinforcement particles, as well as thermal stability, have been evaluated through microhardness tests.
Microscopy and the Solid Solubility Limit in K1-xMnxTaO3 Ceramics
Authors: Tkach Alexander , Vilarinho Paula M. , Almeida Abílio
Published: September 2012

Multiferroic materials, combining at least two of three properties: ferromagnetism, ferroelectricity and ferroelasticity in the same phase, have been widely studied nowadays and have tremendous potential for multifunctional applications, although magnetoelectric multiferroics are difficult to obtain. Recently, dielectric and magnetic anomalies were found to be coupled in the incipient ferroelectrics SrTiO3 and KTaO3 doped with Mn on A-site of ABO3 perovskite lattice.
Microstructure of Mullite-zirconia Fibres Grown by Directional Solidification
Authors: Carvalho R. G. , Pires M. S. , Fernandes A. J. S. , Oliveira F. J. , Monteiro T. , Silva R. F. , Costa F. M.
Published: September 2012

Recently, much attention has been given to directional solidified eutectic (DSE) materials for functional and structural applications. DSE materials take advantage from their microstructural features. Typically, DSE are dense homogeneous materials composed by fine microstructures without grain boundaries (GBs). Since impurities and defects typically concentrate at GBs, their deleterious effects on the mechanical, thermal and electrical properties can thus be minimized.
Morphology Control of BaTiO3 Nanoparticles Prepared by Sol-gel Hydrothermal Method
Authors: Maxim Florentina , Ferreira Paula , Vilarinho Paula M.
Published: September 2012

Barium titanate (BT), a typical ferroelectric material with a tetragonal structure bellow TC ≈125 ºC has found widespread applications especially in electronic devices. However, modern electronics demand very small functional structures and, as a consequence nanostructures of ferroeletrics are being considered. However it was observed that there is a critical size for BT nanostructures below which TC decreases, the paraelectric cubic phase is stabilized at room temperature and then ferroelectricity may no longer exist. These observations have stimulated an exponential growth of research aiming to understand the effect of scaling on the ferroelectric properties. In addition some theoretical studies predicted the enhancement of ferroelectricity in anisotropic “cylindrical” shaped nanoparticles. Therefore, the morphology control and fabrication of ferroelectric nanostructures with different size and shapes are of key importance. Within this context, we demonstrated that the control of the morphology of BT nanoparticulates can be achieved by hydrothermal method.
Grain Growth Anomaly in Ti-rich Strontium Titanate as Revealed by Electron Microscopy
Authors: Amaral L. , Fernandes M. , Senos A. M. R. , Vilarinho P. M. , Harmer M. P.
Published: September 2012

An anomaly in the dependence of the kinetics of grain growth on the temperature for strontium titanate (ST) ceramics is reported in this work. It consists of a decrease of the grain size with increasing sintering temperature. Recently, a drop in the grain boundary mobility of ST in the same temperature range was reported. These observations imply an unusual decrease of the grain size with the increase of the sintering temperature, in agreement with our present results. Although the mobility drop was related to structural changes in grain boundaries, the exact mechanism involved is still unknown. The understanding of this anomaly may offer an alternative way of controlling the microstructure and tuning the dielectric response of ST based compositions without the use of dopants. ST is characterized by high dielectric permittivity, high tunability and low dielectric losses, and is thus a particularly interesting material for capacitor or tunable microwave devices. These properties are very dependent on the stoichiometry, structure and microstructure, in which the role of grain boundaries is fundamentally important. Indeed, increasing attention has been paid to grain boundary structures and nonstoichiometry and to its relation with microstructure and electrical properties. Densification proceeds faster with decreasing Sr/Ti ratio (Ti-rich compositions). Sr-rich samples show narrow grain size distributions, while Ti excess favors enlarged grain size distributions and faceting of the grain boundaries.
Spatial dispersion of interstellar civilizations: a probabilistic site percolation model in three dimensions
Authors: Hair Thomas W. , Hedman Andrew D.
Published: October 2012

A model of the spatial emergence of an interstellar civilization into a uniform distribution of habitable systems is presented. The process of emigration is modelled as a three-dimensional probabilistic cellular automaton. An algorithm is presented which defines both the daughter colonies of the original seed vertex and all subsequent connected vertices, and the probability of a connection between any two vertices. The automaton is analysed over a wide set of parameters for iterations that represent up to 250 000 years within the model's assumptions. Emigration patterns are characterized and used to evaluate two hypotheses that aim to explain the Fermi Paradox. The first hypothesis states that interstellar emigration takes too long for any civilization to have yet come within a detectable distance, and the second states that large volumes of habitable space may be left uninhabited by an interstellar civilization and Earth is located in one of these voids.
Over ‘Sexed’ Regulation and the Disregarded Worker: An Overview of the Impact of Sexual Entertainment Policy on Lap-Dancing Club Workers
Authors: Colosi Rachela
Published: September 2012

In England and Wales, with the introduction of Section 27 of the Policing and Crime Act 2009, lap-dancing clubs can now be licensed as Sexual Entertainment Venues. This article considers such, offering a critique of Section 27, arguing that this legislation is not evidence-based, with lap-dancing policy, like other sex-work policies, often associated with crime, deviance and immorality. Furthermore, it is argued that sex-work policies are gradually being homogenised as well as increasingly criminalised. Other criticisms relate to various licensing loopholes which lead to some striptease venues remaining unlicensed and unregulated, potentially impacting on the welfare of erotic dancers. In addition, restrictions on the numbers of lap-dancing venues may exacerbate dancer unemployment, drawing these women into poverty. Finally, The Policing and Crime Act reflects how the political focus is being directed away from the exploitation of workers, on toissuesrelating to crime and deviance, despite limited evidence to support this focus.
The Effect of Brand on EEG Modulation
Authors: Lucchiari Claudio , Pravettoni Gabriella
Published: September 2012

Consumers often develop close relationships with their preferred brands and goods. To achieve marketing goals, companies need to develop in customers a positive brand attachment. When they succeed, the brand is immediately recognized, it elicits specific responses, and it becomes more difficult to be replaced by competitors. Previous studies have suggested the existence of a relationship between brand evaluation and a reward-related functional circuit. The present study measured brain responses to different brands of mineral water. In particular, we were interested in analyzing the impact of brand attachment on brain modulation. We hypothesized that brand evaluation would be associated with reward processing, and that brain oscillatory activity would be modulated by different expectations based on previous experience. Time-frequency analyses of EEG oscillatory activity were performed on 26 healthy subjects (13 males and 13 females) during water intake of differently labeled glasses of mineral water. Our results confirmed that brand processing is related to activity of the frontocentral reward-related network. Beta activity seems to be modulated by the experience of pleasure associated with a favorite brand, while theta modulation seems to reflect the lack of this experience. In conclusion, our study showed how exposure to a brand can affect EEG modulation. Additionally, we confirmed a possible relationship between brand evaluation and reward processing.
Mechanical and hydraulic properties of Nankai accretionary prism sediments: Effect of stress path
Authors: Kitajima Hiroko , Chester Frederick M. , Biscontin Giovanna
Published: October 2012

We have conducted triaxial deformation experiments along different loading paths on prism sediments from the Nankai Trough. Different load paths of isotropic loading, uniaxial strain loading, triaxial compression (at constant confining pressure, Pc), undrained Pc reduction, drained Pc reduction, and triaxial unloading at constant Pc, were used to understand the evolution of mechanical and hydraulic properties under complicated stress states and loading histories in accretionary subduction zones. Five deformation experiments were conducted on three sediment core samples for the Nankai prism, specifically from older accreted sediments at the forearc basin, underthrust slope sediments beneath the megasplay fault, and overthrust Upper Shikoku Basin sediments along the frontal thrust. Yield envelopes for each sample were constructed based on the stress paths of Pc‐reduction using the modified Cam‐clay model, and in situ stress states of the prism were constrained using the results from the other load paths and accounting for horizontal stress. Results suggest that the sediments in the vicinity of the megasplay fault and frontal thrust are highly overconsolidated, and thus likely to deform brittle rather than ductile. The porosity of sediments decreases as the yield envelope expands, while the reduction in permeability mainly depends on the effective mean stress before yield, and the differential stress after yield. An improved understanding of sediment yield strength and hydromechanical properties along different load paths is necessary to treat accurately the coupling of deformation and fluid flow in accretionary subduction zones.
Deformation during the 1975–1984 Krafla rifting crisis, NE Iceland, measured from historical optical imagery
Authors: Hollingsworth James , Leprince Sébastien , Ayoub François , Avouac Jean‐Philippe
Published: October 2012

We measure the displacement field resulting from the 1975–1984 Krafla rifting crisis, NE Iceland, using optical image correlation. Images are processed using the COSI‐Corr software package. Surface extension is accommodated on normal faults and fissures which bound the rift zone, in response to dike injection at depth. Correlation of declassified KH‐9 spy and SPOT5 satellite images reveals extension between 1977–2002 (2.5 m average opening over 80 km), while correlation of aerial photos between 1957–1990 provide measurements of the total extension (average 4.3 m opening over 80 km). Our results show ∼8 m of opening immediately north of Krafla caldera, decreasing to 3–4 m at the northern end of the rift. Correlation of aerial photos from 1957–1976 reveal a bi‐modal pattern of opening along the rift during the early crisis, which may indicate either two different magma sources located at either end of the rift zone (a similar pattern of opening was observed in the 2005 Afar rift crisis in East Africa), or variations in rock strength along the rift. Our results provide new information on how past dike injection events accommodate long‐term plate spreading, as well as providing more details on the Krafla rift crisis. This study also highlights the potential of optical image correlation using inexpensive declassified spy satellite and aerial photos to measure deformation of the Earth's surface going back many decades, thus providing a new tool for measuring Earth surface dynamics, e.g. glaciers, landsliding, coastal erosion, volcano monitoring and earthquake studies, when InSAR and GPS data are not available.
Coupled transport and reaction kinetics control the nitrate source‐sink function of hyporheic zones
Authors: Zarnetske Jay P. , Haggerty Roy , Wondzell Steven M. , Bokil Vrushali A. , González‐Pinzón Ricardo
Published: October 2012

The fate of biologically available nitrogen (N) and carbon (C) in stream ecosystems is controlled by the coupling of physical transport and biogeochemical reaction kinetics. However, determining the relative role of physical and biogeochemical controls at different temporal and spatial scales is difficult. The hyporheic zone (HZ), where groundwater–stream water mix, can be an important location controlling N and C transformations because it creates strong gradients in both the physical and biogeochemical conditions that control redox biogeochemistry. We evaluated the coupling of physical transport and biogeochemical redox reactions by linking an advection, dispersion, and residence time model with a multiple Monod kinetics model simulating the concentrations of oxygen (O2), ammonium (NH4), nitrate (NO3), and dissolved organic carbon (DOC). We used global Monte Carlo sensitivity analyses with a nondimensional form of the model to examine coupled nitrification‐denitrification dynamics across many scales of transport and reaction conditions. Results demonstrated that the residence time of water in the HZ and the uptake rate of O2 from either respiration and/or nitrification determined whether the HZ was a source or a sink of NO3 to the stream. We further show that whether the HZ is a net NO3 source or net NO3 sink is determined by the ratio of the characteristic transport time to the characteristic reaction time of O2 (i.e., the Damköhler number, DaO2), where HZs with DaO2 < 1 will be net nitrification environments and HZs with DaO2 ≪ 1 will be net denitrification environments. Our coupling of the hydrologic and biogeochemical limitations of N transformations across different temporal and spatial scales within the HZ allows us to explain the widely contrasting results of previous investigations of HZ N dynamics which variously identify the HZ as either a net source or sink of NO3. Our model results suggest that only estimates of residence times and O2uptake rates are necessary to predict this nitrification‐denitrification threshold and, ultimately, whether a HZ will be either a net source or sink of NO3.
Attention to four key principles can promote health outcomes from desert Aboriginal land management
Authors: Davies Jocelyn , Campbell David , Campbell Matthew , Douglas Josie , Hueneke Hannah , LaFlamme Michael , Pearson Diane , Preuss Karissa , Walker Jane , Walsh Fiona
Published: October 2012

We identify four principles that can promote the prospects of health outcomes for desert Aboriginal people from livelihoods engaged with land management. The principles were derived inductively using a grounded theory approach, drawing on primary research that used qualitative and participatory methods, and from relevant literature and theoretical frameworks. International and Australian literature offers evidence that supports desert Aboriginal people’s view that their health depends on their relationship with their land. Engagement with land management can lead desert Aboriginal people to feel that their own actions are consistent with their own sense of the right and proper way for them to behave towards land, family and community. This increased ‘sense of control’ impacts positively on health by moderating the impact of sustained stress from health risk factors in the environment and lifestyle. The four principles focus on underlying characteristics of Aboriginal land management that are important to promoting this increased ‘sense of control’: (1) Aboriginal land management governance recognises and respects Aboriginal custom and tradition, and is adaptive; (2) learning is embraced as a life-long process; (3) relationships are recognised as very important; and (4) partnerships give priority to doing things that all parties agree are important. These principles are presented as hypotheses that warrant further development and testing. While they do not account specifically for the impact of lifestyle and environmental factors on health, we expect that the increased sense of control that desert Aboriginal people are likely to develop when involved in Aboriginal land management that applies these principles will moderate the impact of such factors on their health. The principles offer a starting point for further development of criteria and standards for good practice in Aboriginal land management, potentially including an environmental certification scheme that integrates social and environmental outcomes.
Role for urea in nitrification by polar marine Archaea
Authors: Alonso-Sáez Laura , Waller Alison S. , Mende Daniel R. , Bakker Kevin , Farnelid Hanna , Yager Patricia L. , Lovejoy Connie , Tremblay Jean-Éric , Potvin Marianne , Heinrich Friederike , Estrada Marta , Riemann Lasse , Bork Peer , Pedrós-Alió Carlos , Bertilsson Stefan
Published: October 2012

Despite the high abundance of Archaea in the global ocean, their metabolism and biogeochemical roles remain largely unresolved. We investigated the population dynamics and metabolic activity ofThaumarchaeotain polar environments, where these microorganisms are particularly abundant and exhibit seasonal growth.Thaumarchaeotawere more abundant in deep Arctic and Antarctic waters and grew throughout the winter at surface and deeper Arctic halocline waters. However, in situ single-cell activity measurements revealed a low activity of this group in the uptake of both leucine and bicarbonate (<5%Thaumarchaeotacells active), which is inconsistent with known heterotrophic and autotrophic thaumarchaeal lifestyles. These results suggested the existence of alternative sources of carbon and energy. Our analysis of an environmental metagenome from the Arctic winter revealed thatThaumarchaeotahad pathways for ammonia oxidation and, unexpectedly, an abundance of genes involved in urea transport and degradation. Quantitative PCR analysis confirmed that most polarThaumarchaeotahad the potential to oxidize ammonia, and a large fraction of them had urease genes, enabling the use of urea to fuel nitrification.Thaumarchaeotafrom Arctic deep waters had a higher abundance of urease genes than those near the surface suggesting genetic differences between closely related archaeal populations. In situ measurements of urea uptake and concentration in Arctic waters showed that small-sized prokaryotes incorporated the carbon from urea, and the availability of urea was often higher than that of ammonium. Therefore, the degradation of urea may be a relevant pathway forThaumarchaeotaand other microorganisms exposed to the low-energy conditions of dark polar waters.
Cell-type homologies and the origins of the neocortex
Authors: Dugas-Ford Jennifer , Rowell Joanna J. , Ragsdale Clifton W.
Published: October 2012

The six-layered neocortex is a uniquely mammalian structure with evolutionary origins that remain in dispute. One long-standing hypothesis, based on similarities in neuronal connectivity, proposes that homologs of the layer 4 input and layer 5 output neurons of neocortex are present in the avian forebrain, where they contribute to specific nuclei rather than to layers. We devised a molecular test of this hypothesis based on layer-specific gene expression that is shared across rodent and carnivore neocortex. Our findings establish that the layer 4 input and the layer 5 output cell types are conserved across the amniotes, but are organized into very different architectures, forming nuclei in birds, cortical areas in reptiles, and cortical layers in mammals.
Chlamydia trachomatis
protein GrgA activates transcription by contacting the nonconserved region of σ
66
Authors: Bao Xiaofeng , Nickels Bryce E. , Fan Huizhou
Published: October 2012

The bacterial RNA polymerase holoenzyme consists of a catalytic core enzyme in complex with a σ factor that is required for promoter-specific transcription initiation. Primary, or housekeeping, σ factors are responsible for most of the gene expression that occurs during the exponential phase of growth. Primary σ factors share four regions of conserved sequence, regions 1–4, which have been further subdivided. Many primary σ factors also contain a nonconserved region (NCR) located between subregions 1.2 and 2.1, which can vary widely in length. Interactions between the NCR of the primary σ factor of
Escherichia coli
, σ
70
, and the β′ subunit of the
E. coli
core enzyme have been shown to influence gene expression, suggesting that the NCR of primary σ factors represents a potential target for transcription regulation. Here, we report the identification and characterization of a previously undocumented
Chlamydia trachomatis
transcription factor, designated GrgA (
g
eneral
r
egulator of
g
enes
A
). We demonstrate in vitro that GrgA is a DNA-binding protein that can stimulate transcription from a range of σ
66
-dependent promoters. We further show that GrgA activates transcription by contacting the NCR of the primary σ factor of
C. trachomatis
, σ
66
. Our findings suggest GrgA serves as an important regulator of σ
66
-dependent transcription in
C. trachomatis
. Furthermore, because GrgA is present only in chlamydiae, our findings highlight how nonconserved regions of the bacterial RNA polymerase can be targets of regulatory factors that are unique to particular organisms.