bluuebunny/crossref_metadata_2025 huggingface dataset:
Past dieting is related to rigid control and disinhibition in adolescents from the Québec Family Study
Authors: Gallant Annette R. , Tremblay Angelo , Pérusse Louis , Després Jean-Pierre , Bouchard Claude , Drapeau Vicky
Published: February 2012

Eating behaviour traits of rigid control and disinhibition have been associated with body weight in both adults and adolescents. Moreover, adults reporting a dieting history have increased levels of unhealthy eating behaviours. Against this background, the present study aimed to examine the relationship between dieting history and eating behaviour traits in adolescents. For the purpose of this research, a total of sixty adolescents (aged 15 (sem 2·4) years) from the Québec Family Study completed the Three-Factor Eating Questionnaire (TFEQ) and a questionnaire regarding eating habits. Self-reported current and past dieting were analysed against eating behaviour traits measured by the TFEQ, including all subscales. As the results revealed, few adolescents reported currently dieting (n 3). Adolescents who reported a dieting history (23·3 %) were older (16·9 v. 14·4 years, P < 0·001), were more likely to be female (78·6 v. 41·3 %, P < 0·05) but did not have a significantly higher BMI z-score (1·5 v. 0·9, P = 0·10), although they were more likely to be either overweight or obese (P < 0·01). After correcting for sex, BMI and age, adolescents who reported a dieting history had higher levels of rigid control and disinhibition (P < 0·05–0·0001) than those reporting no dieting history. A greater proportion of adolescents characterised by high rigid control and high disinhibition were past dieters, compared to those characterised by low levels of both behaviour traits (53 v. 4 %). The study arrived at the following conclusions: as observed in adults, adolescents with a history of dieting present unfavourable eating behaviour traits. These behavioural traits may represent an additional challenge to the long-term regulation of body weight.
New insights into the polyphase evolution of the Variscan suture zone: evidence from the Staré Město Belt, NE Bohemian Massif
Authors: JASTRZĘBSKI MIROSŁAW
Published: February 2012

Forming a northern continuation of the Moldanubian Thrust Zone, the Staré Město Belt comprises an E-verging thrust stack of three narrow lithotectonic units that exhibit variations in their respectiveP–Trecords. The upper and lower units form the respective margins of the hanging wall and footwall of the suture zone and are dominated by amphibolite grade metasedimentary successions. The middle unit is defined by an elongated body of MORB-like amphibolites that contains inserts of migmatized mica schists. Integrating both structural studies and pseudosection modelling in the MnNCKFMASH system shows that the present-day tectonic architecture of the Staré Město Belt is the result of a polyphase Variscan evolution. During a frontal, WNW–ESE-directed (in present-day coordinates) collision between the Bohemian Massif terranes and the Brunovistulian terrane, the metasedimentary rocks of the Staré Město Belt experienced tectonic burial to depths corresponding to 7–9 kbar. The continuous indentation and underthrusting of the Brunovistulian terrane led to top-to-the-ESE folding and uplift of these rocks to depths corresponding to 5.5–6.0 kbar at peak temperature. At depths corresponding to 5.5 kbar, the Staré Město Belt underwent subsequent dextral (top-to-the-NNE) shearing that was locally associated with nearly isobaric heating, possibly related to the emplacement of a Carboniferous tonalite body in the axial part of the Staré Město Belt. Subsequent tectonic compression resulted in the Variscan WNW-dipping metamorphic foliations becoming locally (N)NE- or ESE-dipping.
Thyroid hormones in milk and blood of lactating donkeys as affected by stage of lactation and dietary supplementation with trace elements
Authors: Todini Luca , Salimei Elisabetta , Malfatti Alessandro , Ferraro Stefano , Fantuz Francesco
Published: February 2012

The traditional utilization of donkeys (Equus asinus) as dairy animals has recently attracted substantial scientific interest with regard to human nutrition. Donkey milk is well tolerated by infants with cows’ milk allergy, useful in the treatment of human immune-related diseases, in the prevention of atherosclerosis, and in-vitro studies showed an anti-proliferative effect. Active 3-3′-5-triiodothyronine (T3) in colostrum and milk could play different physiological roles, systemic and paracrine, for both the mother and the suckling offspring. The aim was to evaluate whether thyroid hormones (TH) concentrations in milk and blood of lactating donkeys change with the advancing lactation and whether they can be affected by dietary supplementation with several trace elements, some of them directly involved with TH synthesis (I), metabolism (Se) and action (Zn). Sixteen lactating jennies were divided into two groups (CTL and TE). Mixed feed for TE was added with Zn, Fe, Cu, Mn, I, Se and Co. Every 2 weeks milk and blood samples were collected at 11·00. Total concentrations of T3 in milk (T3M) and T3 and T4 in plasma (T3P and T4P) were assayed using ELISA kits, validated for the donkey species. T3M was not correlated with TH concentrations in blood, did not change with the stage of lactation, and was significantly higher in TE (4·09±0·07 ng/ml, mean±se) than in CTL group (3·89±0·08 ng/ml). T4P (81·8±5·2 ng/ml) and T3P (15·2±1 ng/ml) significantly changed with time, but were not significantly affected by dietary treatment. T3P/T4P ratio was significantly lower in TE group. This study indicates that in donkey milk the concentration of T3, a human-like bioactive compound, can be affected by trace elements intake.
Effect of vitamin A deficiency on the immune response in obesity
Authors: García Olga P.
Published: February 2012

Obesity has been associated with low-grade systemic inflammation and with micronutrient deficiencies. Obese individuals have been found to have lower vitamin A levels and lower vitamin A intake compared with normal-weight individuals. Vitamin A plays a major role in the immune function, including innate immunity, cell-mediated immunity and humoral antibody immunity. It has also been recognised recently that vitamin A has important regulatory functions. Vitamin A status has an important effect on the chronic inflammatory response. Vitamin A deficiency increases a T-helper type 1 (Th1) response, elevates levels of pro-inflammatory cytokines, increases the expression of leptin, resistin and uncoupling proteins (UCP) and promotes adipogenesis. The effect of vitamin A deficiency on obesity might be increasing the risk of fat deposition and also the risk of chronic inflammation associated with obesity. Supplementation with vitamin Ain vitroand in animal models has been found to reduce concentrations of adipocytokines, such as leptin and resistin. In conclusion, vitamin A deficiency increases a Th1 response in the presence of obesity and thus, increases the inflammatory process involved in chronic inflammation and fat deposition. The metabolism of leptin and other adipocytokines may play a critical role in the effect of vitamin A deficiency in the inflammatory response observed in obesity.
Similarities and differences between the effects of EPA and DHA on markers of atherosclerosis in human subjects
Authors: Kelley Darshan S. , Adkins Yuriko
Published: February 2012

We have reviewed effects of long chain (LC)n-3 PUFA on markers of atherosclerosis in human subjects with a focus on individual effects of EPA and DHA. Initial results from epidemiological studies suggested that LCn-3 PUFA from fish oils (FO) reduced incidence of CVD; those results have been confirmed in interventional studies. Dietary intervention withn-3 PUFA decreased fasting and postprandial TAG, number of remnant-like chylomicron particles, large VLDL, and total and small dense LDL particles. It increased mean size of LDL particles by increasing number of large and decreasing those of small dense particles. With some exceptions,n-3 PUFA decreased blood pressure (BP) and heart rate (HR), flow-mediated dilation (FMD) and plasma concentrations of inflammatory markers.n-3 PUFA also decreased circulating adhesion molecules and intima-media thickness (IMT) in some but not other studies. For IMT, results varied with the sex and artery being examined. EPA effects on FMD are endothelial cell dependent, while those of DHA seem to be endothelial cell independent. Individually, both EPA and DHA decreased TAG and inflammatory markers, but only DHA decreased HR, BP and number of small dense LDL particles. Results varied because of dose and duration ofn-3 PUFA, EPA:DHA, health status of subjects and other reasons. Future studies are needed to determine optimal doses of EPA and DHA individually, their synergistic, additive or antagonistic effects, and to understand underlying mechanisms. In conclusion,n-3 PUFA decreased several risk factors for atherosclerosis without any serious adverse effects.
Adults with attention deficit hyperactivity disorder: an investigation of age-related differences in behavioural symptoms, neuropsychological function and co-morbidity
Authors: Bramham J. , Murphy D. G. M. , Xenitidis K. , Asherson P. , Hopkin G. , Young S.
Published: February 2012

Background

The outcomes of attention deficit hyperactivity disorder (ADHD) have been studied extensively in the first decades of life, but less is known about ADHD in adulthood. Hence we investigated cross-sectional age-related differences in behavioural symptoms, neuropsychological function and severity of co-morbid disorders within a clinically referred adult ADHD population.

Method

We subdivided 439 referrals of individuals with ADHD (aged 16–50 years) into four groups based on decade of life and matched for childhood ADHD severity. We compared the groups on measures of self- and informant-rated current behavioural ADHD symptoms, neuropsychological performance, and self-rated co-morbid mood and anxiety symptoms.

Results

There was a significant age-related reduction in the severity of all ADHD symptoms based on informant-ratings. In contrast, according to self-ratings, inattentive symptoms increased with age. Neuropsychological function improved across age groups on measures of selective attention and response inhibition. There was a mild correlation between the severity of depression symptoms and increasing age.

Conclusions

This observational study suggests that, in adulthood, ADHD symptoms as measured using informant-ratings and neuropsychological measures continue to improve with increasing age. However the subjective experience of people with ADHD is that their symptoms worsen. This dichotomy may be partially explained by the presence of co-morbid affective symptoms. The main limitation of the study is that it is cross-sectional rather than longitudinal, and the latter design would provide more conclusive evidence regarding age-related changes in an adult ADHD population.
A modular version of Klyachko's theorem on Lie representations of the general linear group
Authors: BRYANT R. M. , JOHNSON MARIANNE
Published: February 2012

Klyachko, in 1974, considered the tensor and Lie powers of the natural module for the general linear group over a field of characteristic 0 and showed that nearly all of the irreducible submodules of the rth tensor power also occur up to isomorphism as submodules of the rth Lie power. Here we prove an analogue for infinite fields of prime characteristic by showing, with some restrictions on r, that nearly all of the indecomposable direct summands of the rth tensor power also occur up to isomorphism as summands of the rth Lie power.
Large deviations of the limiting distribution in the Shanks–Rényi prime number race
Authors: LAMZOURI YOUNESS
Published: February 2012

Let q ≥ 3, 2 ≤ r ≤ φ(q) and a1, . . ., ar be distinct residue classes modulo q that are relatively prime to q. Assuming the Generalized Riemann Hypothesis (GRH) and the Linear Independence Hypothesis (LI), M. Rubinstein and P. Sarnak [11] showed that the vector-valued function Eq;a1, . . ., ar(x) = (E(x;q,a1), . . ., E(x;q,ar)), where $E(x;q,a)= ({\log x}/{\sqrt{x}})(\phi(q)\pi(x;q,a)-\pi(x))$, has a limiting distribution μq;a1, . . ., ar which is absolutely continuous on $\mathbb{R}^r$. Furthermore, they proved that for r fixed, μq;a1, . . ., ar tends to a multidimensional Gaussian as q → ∞. In the present paper, we determine the exact rate of this convergence, and investigate the asymptotic behavior of the large deviations of μq;a1, . . ., ar.
Coins in Context: Local Economy, Value and Practice on the East African Swahili Coast
Authors: Wynne-Jones Stephanie , Fleisher Jeffrey
Published: February 2012

Coinage occupies an unusual position in archaeological research. Thriving scholarship on numismatics and monetary history ensures that the objects themselves are well-studied, often seen as an indication of chronology and of stylistic and commercial links. Yet coins might also be analysed as artefacts, and explored as part of the symbolic world of material culture through which archaeologists understand meaning and value in past societies. Using a recently-excavated assemblage of medieval Kilwa-type coins from Songo Mnara on the East African Swahili coast, this article explores the multiple ways that value was ascribed and created through use, rejecting a simple dichotomy between substantive and formal value. Attention is given to the contexts of the coins, which enables a discussion of the relationship between power and the constitution of value, the circulation and use of coins among townspeople, and their use within ritual and commemorative activity.
Terminal Classic Maya Heterodoxy and Shrine Vernacularism in the Sibun Valley, Belize
Authors: McAnany Patricia A.
Published: February 2012

A monolithic view of Classic Maya society as dominated by divine rulers who inexplicably ceased to erect monuments with long-count dates during the ninth century is examined by reference to new information from Terminal Classic sites in the Sibun Valley of Belize. In this locale and elsewhere, the construction of circular one-room buildings — with striking associated artefacts — may be interpreted as signalling social tensions between the orthodoxy of Classic Maya divine rulers and the more heterodoxic beliefs and practices associated with circular structures built at the end of the Classic period. The round buildings are contextualized within the diversity of architectural expressions of the Sibun Valley and also within a peninsula-wide network of shrines. The chronological placement and character of the Sibun shrines is discussed by way of radiocarbon assays, obsidian sourced by INAA, and raw materials used for groundstone at sites throughout the valley. The presence of marine shell and speleothems — likely used as architectural adornment — found in close association with Sibun Valley round buildings permits discussion of the manner in which elements of the local effected a translation of heterodoxic tenets into vernacularized shrine architecture.
Characteristic formulae for fixed-point semantics: a general framework
Authors: ACETO LUCA , INGOLFSDOTTIR ANNA , LEVY PAUL BLAIN , SACK JOSHUA
Published: February 2012

The concurrency theory literature offers a wealth of examples of characteristic-formula constructions for various behavioural relations over finite labelled transition systems and Kripke structures that are defined in terms of fixed points of suitable functions. Such constructions and their proofs of correctness have been developed independently, but have a common underlying structure. This paper provides a general view of characteristic formulae that are expressed in terms of logics that have a facility for the recursive definition of formulae. We show how several examples of characteristic-formula constructions in the literature can be recovered as instances of the proposed general framework, and how the framework can be used to yield novel constructions. The paper also offers general results pertaining to the definition of co-characteristic formulae and of characteristic formulae expressed in terms of infinitary modal logics.
Modal logic and the approximation induction principle
Authors: GAZDA MACIEJ , FOKKINK WAN
Published: February 2012

We prove a compactness theorem in the context of Hennessy–Milner logic and use it to derive a sufficient condition on modal characterisations for the approximation induction principle to be sound modulo the corresponding process equivalence. We show that this condition is necessary when the equivalence in question is compositional with respect to the projection operators. Furthermore, we derive different upper bounds for the constructive version of the approximation induction principle with respect to simulation and decorated trace semantics.
INDETERMINACY AND PERIOD LENGTH UNDER BALANCED BUDGET RULES
Authors: Anagnostopoulos Alexis , Giannitsarou Chryssi
Published: February 2012

We analyze the importance of the frequency of decision making for macroeconomic dynamics, in the context of a simple, well-known business cycle model with balanced budget rules. We explain how the frequency of decision making (period length) and the measurement unit of time (calibration frequency) differ and examine how local stability is affected by changes in the period length. We find that as the period grows longer, indeterminacy occurs less often. This may have significant quantitative implications: for the model at hand, there is a wide range of economically relevant labor tax rates (from 30% to 38%) for which the continuous-time model gives indeterminacy, whereas the discrete-time model has determinate dynamics.
Distinguishing between Mineral Paint and Carbon Paint on Ancestral Puebloan Pottery
Authors: Pendleton M. W. , Washburn D. K. , Ellis E. A. , Pendleton B. B.
Published: February 2012

Archaeologists have found that the elements present in the pigments used on Ancestral Puebloan black-on-white painted pottery are an important descriptive attribute. They typically describe the pigments used to produce these painted designs as either carbon-based (containing primarily organic compounds) or mineral-based (containing primarily iron compounds), although in some cases these pigments are combined or “mixed”.
Early Days of Electron Diffraction
Authors: Bigelow Wilbur C.
Published: February 2012

This year marks the eighty-fifth anniversary of the discovery of electron diffraction. In addition to its important role in materials characterization, electron diffraction contributed substantially to several Nobel Prizes, to foundations of quantum mechanics, and to the development of the theory of covalent bonding in organic chemistry. What follows is a personal narrative describing the development of this technique.
Running Digital Micrograph on Linux and Mac OSX
Authors: Hovden Robert
Published: February 2012

Gatan Digital Micrograph (DM) software is considered an industry standard among microscopists. The offline DM application is freely available from Gatan. Unfortunately, DM software has been designed to run only on Microsoft Windows operating systems, thus distancing the microscopy community from popular Unix-based systems, such as Linux or Mac OSX. An ad hoc solution to this problem has required a virtualized Windows operating system running on top of the user's native operating system. This is not only slow, having to emulate each processor instruction, but also requires installation and licensing of Windows and the virtualization software. However, with the aid of open-source resources, it is possible to run DM natively on Linux and Mac OSX (Figure 1). This article was written as a guide with easy-to-follow installation instructions to liberate users from the Windows emulation pidgeonhole and enable them to freely analyze data on Unix-based systems.
Preparation Methods for EM Studies of Polymers
Authors: Hassander Helen
Published: February 2012

Polymers are organic materials, and most of the preparation methods for transmission electron microscopy (TEM) are much the same as for biological specimens. Bulk samples are cut in the ultramicrotome, and latex particles are dropped onto a Formvar-coated grid. However, the staining possibilities of polymers are limited. Polymers mainly consist of saturated hydrocarbon, and unlike biomaterial there are few reactive groups for staining. This has two consequences for the microscopist: it is difficult to obtain contrast, and the sample is very beam-sensitive. Biological samples are also organic material and sensitive to the beam, but the staining process converts them into materials that are usually stable to the beam.
NetNotes
Authors: Phillips Thomas E.
Published: February 2012

Selected postings to the Microscopy Listserver from November 1, 2011 to January 1, 2012. Complete listings and subscription information can be obtained at http://www.microscopy.com. Postings may have been edited to conserve space or for clarity.
Psychiatric epidemiology now: some achievements and prospects
Authors: Henderson A. S.
Published: February 2012

Aims.

It is timely to ask what epidemiology has brought to our knowledge about mental illness and what information is proving of particular value. In this task, the first step is to identify the truly fundamental questions that the epidemiology of mental disorders should be expected to answer. This review is selectively directed at four such questions.

Methods.

A small number of significant publications were identified.

Results.

The extent to which some major questions in epidemiology have been answered is examined.

Conclusions.

When considered alongside epidemiological knowledge elsewhere in medicine, psychiatric epidemiology has indisputably proved to be a powerful tool. Descriptive studies have been particularly useful for advocacy and policy, while analytic studies of aetiology have yielded some valuable clues. There are now signs that linkage with neuroscience will bring further progress in understanding the causes of mental disorders.
Insights on the kinematics of the India‐Eurasia collision from global geodynamic models
Authors: Zahirovic Sabin , Müller R. Dietmar , Seton Maria , Flament Nicolas , Gurnis Michael , Whittaker Joanne
Published: February 2012

The Eocene India‐Eurasia collision is a first order tectonic event whose nature and chronology remains controversial. We test two end‐member collision scenarios using coupled global plate motion‐subduction models. The first, conventional model, invokes a continental collision soon after ∼60 Ma between a maximum extent Greater India and an Andean‐style Eurasian margin. The alternative scenario involves a collision between a minimum extent Greater India and a NeoTethyan back‐arc at ∼60 Ma that is subsequently subducted along southern Lhasa at an Andean‐style margin, culminating with continent‐continent contact at ∼40 Ma. Our numerical models suggest the conventional scenario does not adequately reproduce mantle structure related to Tethyan convergence. The alternative scenario better reproduces the discrete slab volumes and their lateral and vertical distribution in the mantle, and is also supported by the distribution of ophiolites indicative of Tethyan intraoceanic subduction, magmatic gaps along southern Lhasa and a two‐stage slowdown of India. Our models show a strong component of southward mantle return flow for the Tethyan region, suggesting that the common assumption of near‐vertical slab sinking is an oversimplification with significant consequences for interpretations of seismic tomography in the context of subduction reference frames.
A synoptic view of the distribution and connectivity of the mid‐crustal low velocity zone beneath Tibet
Authors: Yang Yingjie , Ritzwoller Michael H. , Zheng Yong , Shen Weisen , Levshin Anatoli L. , Xie Zujun
Published: February 2012

Based on 1–2 years of continuous observations of seismic ambient noise data obtained at more than 600 stations in and around Tibet, Rayleigh wave phase velocity maps are constructed from 10 s to 60 s period. A 3‐D Vsv model of the crust and uppermost mantle is derived from these maps. The 3‐D model exhibits significant apparently inter‐connected low shear velocity features across most of the Tibetan middle crust at depths between 20 and 40 km. These low velocity zones (LVZs) do not conform to surface faults and, significantly, are most prominent near the periphery of Tibet. The observations support the internal deformation model in which strain is dispersed in the deeper crust into broad ductile shear zones, rather than being localized horizontally near the edges of rigid blocks. The prominent LVZs are coincident with strong mid‐crustal radial anisotropy in western and central Tibet and probably result at least partially from anisotropic minerals aligned by deformation, which mitigates the need to invoke partial melt to explain the observations. Irrespective of their cause in partial melt or mineral alignment, mid‐crustal LVZs reflect deformation and their amplification near the periphery of Tibet provides new information about the mode of deformation across Tibet.
Velocity‐dependent capillary pressure in theory for variably‐saturated liquid infiltration into porous media
Authors: Hilpert Markus
Published: February 2012

Standard theory for liquid infiltration into porous media cannot explain saturation overshoot at an infiltration front. Based on a recent generalization of the Green‐Ampt approach, a new theory for variably‐saturated flow is presented that assumes that capillary pressure does not only depend on liquid content but also on the flow velocity. The Eulerian expression for the nonequilibrium capillary pressure is rotationally invariant and attempts to capture the conjecture that dynamic effects are more pronounced if flow is associated with moving fluid‐fluid interfaces which cause a dynamic contact angle. The new theory correctly predicts how overshoot depends on the downstream and upstream liquid contents as well as on grain size. The theory also yields the hydrostatic pressure distribution in the liquid and allows for liquid contents exceeding the saturated liquid content of the main imbibition curve that may occur for overshoot.
Detection and projection of carbonate dissolution in the water column and deep‐sea sediments due to ocean acidification
Authors: Ilyina Tatiana , Zeebe Richard E.
Published: February 2012

Dissolution of fossil fuel CO2 in seawater results in decreasing carbonate ion concentration and lowering of seawater pH with likely negative impacts for many marine organisms. We project detectable changes in carbonate dissolution and evaluate their potential to mitigate atmospheric CO2 and ocean acidification with a global biogeochemistry model HAMOCC forced by different CO2 emission scenarios. Our results suggest that as the anthropogenic CO2 signal penetrates into ocean interior, the saturation state of carbonate minerals will drop drastically – with undersaturation extending from the ocean floor up to 100–150 m depth in the next century. This will induce massive dissolution of CaCO3 in the water column as well as the sediment, increasing the Total Alkalinity (TA) by up to 180 μmol kg−1 at the surface and in the ocean interior over the next 2500 years. Model results indicate an inhomogeneous response among different ocean basins: Atlantic carbonate chemistry responds faster and starts recovering two millennia after CO2 emissions cease, which is not the case in the Pacific. CaCO3rain stops in the Pacific Ocean around 2230. Using an observation‐derived detection threshold for TA, we project detectable dissolution‐driven changes only by the year 2070 in the surface ocean and after 2230 and 2500 in the deep Atlantic and Pacific respectively. We show that different model assumptions regarding dissolution and calcification rates have little impact on future projections. Instead, anthropogenic CO2 emissions overwhelmingly control the degree of perturbation in ocean chemistry. In conclusion, ocean carbonate dissolution has insignificant potential in mitigating atmospheric CO2 and ocean acidification in the next millennia.
Cargo ubiquitination is essential for multivesicular body intralumenal vesicle formation
Authors: MacDonald Chris , Buchkovich Nicholas J , Stringer Daniel K , Emr Scott D , Piper Robert C
Published: February 2012

The efficient formation of a variety of transport vesicles is influenced by the presence of cargo, suggesting that cargo itself might have a defining role in vesicle biogenesis. However, definitive in vivo experiments supporting this concept are lacking, as it is difficult to eliminate endogenous cargo. The Endosomal Sorting Complexes Required for Transport (ESCRT) apparatus sorts ubiquitinated membrane proteins into endosomal intralumenal vesicles (ILVs) that accumulate within multivesicular bodies. Here we show that cargo ubiquitination is required for effective recruitment of the ESCRT machinery onto endosomal membranes and for the subsequent formation of ILVs.
DeSUMOylating isopeptidase: a second class of SUMO protease
Authors: Shin Eun Ju , Shin Hyun Mi , Nam Eori , Kim Won Seog , Kim Ji‐Hoon , Oh Byung‐Ha , Yun Yungdae
Published: February 2012

The modification of proteins by small ubiquitin‐like modifier (SUMO) is crucial for the regulation of diverse cellular processes. Protein SUMOylation is reversed by isopeptidases, collectively known as deSUMOylases. Only one family of SUMO‐specific proteases has been described so far: the sentrin‐specific proteases (SENP). Here, we identify and characterize a new deSUMOylase, which we have named DeSI‐1 (DeSumoylating Isopeptidase 1). We describe BZEL—a new transcriptional repressor—as substrate of DeSI‐1. DeSI‐1 catalyses the deSUMOylation, but not the deubiquitination, of BZEL. Furthermore, the SENP substrates PML and ΔNp63 are not deSUMOylated by DeSI‐1, suggesting that SENP and DeSI enzymes recognize different sets of substrates. Together, these data identify a second class of SUMO proteases.
Annealing temperature dependence of exchange bias in BiFeO3/CoFe bilayers
Authors: Yu T. , Naganuma H. , Wang W. X. , Ando Y. , Han X. F.
Published: February 2012

BiFeO3/CoFe bilayers with different BiFeO3 (BFO) crystalities were fabricated by chemical solution deposition and sputtering method. Exchange bias has been successfully induced in these bilayers by post-annealing. The annealing temperature dependence of exchange bias as well as coercivity was investigated. Two kinds of annealing temperature dependence behaviors were observed. It is found that, similar to the conventional antiferromagnet/ferromagnet system, the temperature dependence of exchange bias is dominated by direct interface coupling, and the crystality of BFO has no profound effect on exchange bias.
Relationships between crystal structure and magnetic properties in type-A heteroepitaxial MnAs thin films
Authors: Song J. H. , Cui Y. , Ketterson J. B.
Published: February 2012

We grew heteroepitaxial type-A MnAs thin films on GaAs(001) and Si(001) substrates and compared their crystal structures and magnetic properties. The type-A MnAs on the GaAs(001) substrate shows similar structural and magnetic properties as those in bulk form. However, the structure of the type-A MnAs on the Si(001) substrate is compressed and stretched along the MnAs[1¯100] and MnAs[1¯1¯20] directions, respectively, and exhibits weak ferromagnetism with a Tc exceeding 400 K. These experimental observations indicate that the magnetic characteristics of MnAs are strongly correlated to the material’s crystal structure.
The sweep rate dependence of the electrical control of magnetic coercivity
Authors: Mardana A. , Ducharme Stephen , Adenwalla S.
Published: February 2012

The sweep rate dependence of the coercive field in magnetic thin films is well-known. Here we present an experimental investigation of the dependence of electric field control of magnetization on the magnetic field sweep rate. Our sample is a ferroelectric/ferromagnetic heterostructure, with a soft polymer ferroelectric in contact with a transition metal ferromagnet, Co. Previous work on these heterostructures revealed a large change in coercive field and anisotropy when the ferroelectric polarization was switched from up to down. The present work shows that faster sweep rates increase the changes in coercive field that arise from switching the ferroelectric polarization. Our data indicate that the field sweep rate is an important parameter in the investigation of magnetoelectric coupling.
Spin state and structural changes at the metal-insulator transition in YBaCo2O5.5 by synchrotron x-rays
Authors: Padilla-Pantoja J. , Frontera C. , Herrero-Martín J. , García-Muñoz J. Luis
Published: February 2012

Synchrotron x-ray diffraction and absorption, together with magnetic and thermoelectric measurements, have been used to investigate the mechanism driving the metal to insulator transition in YBaCo2O5.50. Results show a structural and magnetic transition concomitant with the metal to insulator transition. Absorption spectroscopy at the Co L3 edge as a function of temperature reveals minor changes across the transition. The set of experimental results are hardly conciliative with a high to low spin state change of Co ions at octahedral sites in this cobaltite.
Reduction of switching current density in perpendicular magnetic tunnel junctions by tuning the anisotropy of the CoFeB free layer
Authors: Rahman M. T. , Lyle A. , Khalili Amiri P. , Harms J. , Glass B. , Zhao H. , Rowlands G. , Katine J. A. , Langer J. , Krivorotov I. N. , Wang K. L. , Wang J. P.
Published: February 2012

The spin torque switching behavior of perpendicular magnetic tunnel junctions consisting of a CoFeB free layer and a CoFeB/Ru/(Co/Pd)n exchanged coupled fixed layer is investigated. At first, the Ru and CoFeB layer thickness is tuned in the CoFeB/Ru/(Co/Pd)n structure to form a ferromagnetically exchange coupled structure with a strong PMA at an annealing treatment of 325 °C for 1 h. Then it is shown that that the CoFeB free layer thickness plays an important role in the switching current density. The switching current density decreases with the increase of the CoFeB free layer thickness. A minimum switching current density of 1.87 MA/cm2 is achieved for a device with 60 nm diameter. The mechanism involved in the switching current reduction with the decrease of CoFeB free layer thickness is also studied.
Measuring and understanding write width and off-track as a function of linear density in perpendicular recording
Authors: Fernandez-de-Castro Juan , Sandler Gene , Hurben Michel , Lu Pu-Ling , Curland Nathan
Published: February 2012

Multiple techniques have been developed and used to characterize the width of a written track in perpendicular recording. This work investigates written tracks using the WPE (write plus erase) test based on writing the main track at a given density and trimming both sides of the track multiple times with another density. The edge of the original track, after each trimming step, is characterized by a narrow band measurement of the read-back signal as a function of cross-track position. The use of a narrow band filter improves the test SNR and helps separate the track into 2 sections: A good region (track center) and a degraded region (track edge). Test and micro-magnetic analysis were used under multiple linear densities for the main track and for the trimming tracks. The results indicate that the WPE value decreases as the density increased between 200 kfci and 1500 kfci. For densities lower than 200 kfci and higher than 1500 kfci, the WPE value does not change significantly. When the main track was fixed at 200 kfci, increasing the trimming density resulted in a higher WPE. Using a micro-magnetic model and spin-stand tests, it is demonstrated that the apparent increase in WPE is caused by a region with opposite polarity at the edge of the main track (in the media) produced by the magneto-static (demagnetization) field generated by the main track. The section with opposite polarity is found to be coherent with the main track. During the read-back process, the field from the opposite polarity region in the media is integrated by the reader (read sensitivity function) and subtracted from the main track signal. The result is a loss in signal at the track edge that yields a larger WPE value. This phenomenon could have a direct impact on shingled recording.
Structure of Marangoni-driven singularities
Authors: Krechetnikov R.
Published: February 2012

This work presents an analytical study of the structure of steady Marangoni-driven singularities in the context of chemical-reaction driven tip-streaming, which identifies the conditions when such singularities are observable. As motivated by experimental observations of the conical symmetry of the problem, one can construct self-similar solutions of the Stokes equations, which are singular at the tip; these solutions, however, provide no information on the thread structure which is responsible for a resolution of the singularity via tip-streaming. The cone-tip singularity is resolved here with the help of asymptotic matching of the cone and thread solutions using slender jet approximation, which gives an explicit asymptotic formula for the thread radius and thus of the emitted droplets size as a function of physical parameters governing the problem.
Field emission from single-, double-, and multi-walled carbon nanotubes chemically attached to silicon
Authors: Shearer Cameron J. , Fahy Adam , Barr Matthew G. , Moore Katherine E. , Dastoor Paul C. , Shapter Joseph G.
Published: February 2012

The chemical attachment and field emission (FE) properties of single-walled carbon nanotubes (SWCNTs), double-walled carbon nanotubes (DWCNTs), and multi-walled carbon nanotubes (MWCNTs) chemically attached to a silicon substrate have been investigated. A high density of CNTs was revealed by atomic force microscopy imaging with orientation varying with CNT type. Raman spectroscopy was used to confirm the CNT type and diameter on the surfaces. The field emission properties of the surfaces were studied and both current-voltage and Fowler-Nordheim plots were obtained. The SWCNTs exhibited superior FE characteristics with a turn-on voltage (Eto) of 1.28 V μm−1 and electric field enhancement factor (β) of 5587. The DWCNT surface showed an Eto of 1.91 V μm−1 and a β of 4748, whereas the MWCNT surface exhibited an Eto of 2.79 V μm−1 and a β of 3069. The emission stability of each CNT type was investigated and it was found that SWCNTs produced the most stable emission. The differences between the FE characteristics and stability are explained in terms of the CNT diameter, vertical alignment, and crystallinity. The findings suggest that strength of substrate adhesion and CNT crystallinity play a major role in FE stability. Comparisons to other FE studies are made and the potential for device application is discussed.
Real-time measurement system for tracking birefringence, weight, thickness, and surface temperature during drying of solution cast coatings and films
Authors: Unsal E. , Drum J. , Yucel O. , Nugay I. I. , Yalcin B. , Cakmak M.
Published: February 2012

This paper describes the design and performance of a new instrument to track temporal changes in physical parameters during the drying behavior of solutions, as well as curing of monomers. This real-time instrument follows in-plane and out-of-plane birefringence, weight, thickness, and surface temperature during the course of solidification of coatings and films through solvent evaporation and thermal or photocuring in a controlled atmosphere. It is specifically designed to simulate behavior of polymer solutions inside an industrial size, continuous roll-to-roll solution casting line and other coating operations where resins are subjected to ultraviolet (UV) curing from monomer precursors. Controlled processing parameters include air speed, temperature, initial cast thickness, and solute concentration, while measured parameters are thickness, weight, film temperature, in-plane and out-of-plane birefringence. In this paper, we illustrate the utility of this instrument with solution cast and dried poly (amide-imide)/DMAc (Dimethylacetamide) solution, water based black paint, and organo-modified clay/NMP (N-Methylpyrrolidone) solution. In addition, the physical changes that take place during UV photo polymerization of a monomer are tracked. This instrument is designed to be generic and it can be used for tracking any drying/swelling/solidification systems including paper, foodstuffs such as; grains, milk as well as pharmaceutical thin paste and slurries.
Effect of site-disorder on magnetism and magneto-structural coupling in gallium ferrite: A first-principles study
Authors: Roy Amritendu , Prasad Rajendra , Auluck Sushil , Garg Ashish
Published: February 2012

We report a first-principles study of the magnetic properties, cation site disorder effect on magnetism and magneto-structural coupling in multiferroic gallium ferrite (GFO) using the local spin density approximation (LSDA+U) of the density functional theory. The calculation of the ground state A-type antiferromagnetic structure predicts magnetic moments consistent with the experiments while consideration of spin-orbit coupling yields a net orbital moment also in good accordance with the experiment. We find that though cation site disorder is not spontaneous in the ground state, interchange between octahedrally coordinated Fe2 and Ga2 sites is most favored in the disordered state. The results show that ferrimagnetism in GFO is primarily due to Ga-Fe site disorder such that Fe spins at Ga1 and Ga2 sites are antiferromagnetically aligned while maintaining ferromagnetic coupling between Fe spins at Ga1 and Fe1 sites as well as between Fe spins at Ga2 and Fe2 sites. Thus we are able to explain the origin of ferrimagnetism in GFO based on cation site disorder. Our calculations, further predict the presence of magneto-structural coupling in GFO which has been recently observed experimentally.
A class of Lorenz-like systems
Authors: Lainscsek Claudia
Published: February 2012

The transformation of a three-dimensional dynamical system to its differential model can be used to identify different nonlinear dynamical systems that share the same time series of one of its variables. This transformation then can be used to find classes of nonlinear dynamical systems with similar dynamical behavior.
Ring like self assembled Ni nanoparticles based biosensor for food toxin detection
Authors: Kalita Prasanta , Singh Jay , Kumar Singh Manish , Solanki Pratima R. , Sumana G. , Malhotra B. D.
Published: February 2012

The self-assembled ring like nickel (RnNi ∼ 10-20 nm) nanoparticles have been prepared by pulsed laser ablation method and confirmed by transmission electron microscopy. These RnNi nanoparticles electrophoretically deposited onto the indium-tin-oxide (ITO) glass substrate have been functionalized with dimethyl sulfoxide (DMSO) for covalent immobilization of anti-aflatoxin (a-AfB1) monoclonal antibodies and bovine serum albumin as blocking agent. The electrochemical response studies of a-AfB1/DMSO/RnNi-film/ITO bioelectrode reveal linearity as 5-100 ngdL−1, detection limit of 32.7 ngdL−1, sensitivity of 0.59 μA/ng dL−1, and shelf-life of 60 days. The low value (1.3 × 1014 molL−1) of association constant (Ka) shows high affinity towards aflatoxin.
The polarization field dependence of Ti/Al based Ohmic contacts on N-type semipolar GaN
Authors: Chung Roy B. , Chen Hung-Tse , Pan Chih-Chien , Ha Jun-Seok , DenBaars Steven P. , Nakamura Shuji
Published: February 2012

We report on the polarization field dependence of the Ti/Al based n-type contacts on various polar and semipolar GaN planes. The contact resistance of the metal contacts on N-face GaN could be lowered by photoelectrochemical (PEC) etching, which formed a pyramidal feature on the surface with {101¯1¯} facets. The contact resistance on the semipolar (101¯1¯) surface was 6.3 × 10−5 Ω cm2, showing even lower contact resistance than the PEC etched N-face when annealed at 450 °C. Among few semipolar planes, (101¯1¯), (112¯2¯), and (112¯2), the contact resistance was the lowest with (112¯2¯) plane, which is the plane with the stronger polarization field than (101¯1¯) and more Ga rich surface than (112¯2) plane.
Soil water potential does not affect leaf morphology or cuticular characters important for palaeo-environmental reconstructions in southern beech, Nothofagus cunninghamii (Nothofagaceae)
Authors: Hovenden Mark J. , Vander Schoor Jacqueline K.
Published: February 2012

Leaf form is closely related to local prevailing abiotic conditions and thus the morphology of fossil and sub-fossil leaves is often used to reconstruct both historical and palaeo-environmental conditions. However, palaeo-environmental reconstruction is difficult because leaf form is controlled potentially by many interacting environmental factors such as temperature, CO2 concentration, light and water availability. We used a glasshouse trial to investigate the impact of water availability on the leaf and cuticle morphology of a species important for palaeo-environmental reconstruction, the southern beech, Nothofagus cunninghamii. We found that reducing soil water potential to –0.2 or –0.5 MPa had no impact on leaf form or cuticular characters, despite reducing leaf carbon assimilation and severely restricting plant growth. Although plant accession affected many leaf characters, there were few significant impacts of altitude of origin and no substantial interactions between altitude of origin and soil water potential. Thus, both cuticular and gross leaf morphology seem to be stable across a range of soil water potentials in this species, meaning that palaeo-environmental signals from this species are unlikely to be affected by changes in water availability.
Population structure in the clonal, woody wetland plant Melaleuca ericifolia (Myrtaceae): an analysis using historical aerial photographs and molecular techniques
Authors: Robinson Randall W. , James Elizabeth A. , Boon Paul I.
Published: February 2012

Analyses of historical aerial photographs from 1957 to 2003 were combined with two molecular techniques to examine population structure of the swamp paperbark (Melaleuca ericifolia Sm., Myrtaceae) in Dowd Morass, a large, brackish-water wetland of the Gippsland Lakes, Australia. Molecular markers (microsatellites and inter-simple sequence repeats) demonstrated that the large, dome-shaped stands of M. ericifolia evident in the field were individual genets and that adjacent genets did not intermingle. The development of 18 individual stands visible in aerial photographs from 1964 to 2003, but absent from 1957 images, allowed us to calculate that stands expanded at (individual) mean rates of 25–77 m2 year–1 over the period 1964–2003. Rates of lateral expansion, however, varied significantly between 1964 and 2003; the mean rates were highest in 1978–1982 and 1982–1991 (75 ± 7 and 73 ± 9 m2 year–1, respectively) and significantly lower in 1991–2003 (45 ± 3 m2 year–1). A slowing of lateral expansion rate may indicate stand senescence, although competition and space limitations as clones abut each other may also be relevant processes. Clonality has several important implications for the conservation and rehabilitation of Melaleuca-dominated wetlands in south-eastern Australia, including the ability of plants to maintain themselves under adverse hydrological and salinity regimes.