bluuebunny/crossref_metadata_2025 huggingface dataset:
Validation of new ultrasound parameters for quantifying pelvic floor muscle contraction
Authors: Yang S.‐H. , Huang W.‐C. , Yang S.‐Y. , Yang E. , Yang J.‐M.
Published: March 2009

Objective

To determine the reliability and validity of new ultrasound parameters, measured in the polar coordinate system, for quantifying pelvic floor muscle action.

Methods

This was a prospective study, from January 2005 to December 2007, in 209 women with urodynamic stress incontinence, to validate new ultrasound parameters for quantifying pelvic floor muscle contraction. The examination of each patient included intravaginal digital palpation of voluntary pelvic floor muscle contractility and an ultrasound assessment of the positions of the bladder neck and anorectal junction at rest and during pelvic floor muscle contraction. The position of the bladder neck was expressed by bladder neck angle and bladder neck distance from the lower border of the pubic symphysis, and the position of the anorectal junction was expressed by the levator hiatal angle and sagittal hiatal diameter. The vector lengths of the motion of the bladder neck and anorectal junction during pelvic floor muscle contraction were calculated from the positions at rest and during pelvic floor muscle contraction by mathematical formulae.

Results

There was good inter‐ and intraobserver reliability of measurement of ultrasound parameters on stored volumes. During pelvic floor muscle contraction, elevated bladder neck distance and shortened sagittal hiatal diameter were valid parameters representing stronger pelvic floor muscle contractility, with shortened sagittal hiatal diameter having the best correlation (r = − 0.348, P < 0.001).

Conclusion

The methods used in this study appear to be reliable for quantifying pelvic floor muscle action. The bladder neck distance with respect to the lower border of the pubic symphysis and the sagittal hiatal diameter were both valid parameters reflecting PFM contractility. Copyright © 2009 ISUOG. Published by John Wiley & Sons, Ltd.
Bayesian Model Comparison for the Order Restricted RC Association Model
Authors: Iliopoulos G. , Kateri M. , Ntzoufras I.
Published: March 2009

Association models constitute an attractive alternative to the usual log-linear models for modeling the dependence between classification variables. They impose special structure on the underlying association by assigning scores on the levels of each classification variable, which can be fixed or parametric. Under the general row-column (RC) association model, both row and column scores are unknown parameters without any restriction concerning their ordinality. However, when the classification variables are ordinal, order restrictions on the scores arise naturally. Under such restrictions, we adopt an alternative parameterization and draw inferences about the equality of adjacent scores using the Bayesian approach. To achieve that, we have constructed a reversible jump Markov chain Monte Carlo algorithm for moving across models of different dimension and estimate accurately the posterior model probabilities which can be used either for model comparison or for model averaging. The proposed methodology is evaluated through a simulation study and illustrated using actual datasets.
Total Hip Arthroplasty in Rapidly Destructive Osteoarthritis of the Hip: A Case Series
Authors: Kuo Alfred , Ezzet Kace A. , Patil Shantanu , Colwell Clifford W.
Published: March 2009

Rapidly destructive osteoarthritis (RDO) of the hip is a rare condition characterized by rapid joint degeneration and destruction similar to findings of infection, osteonecrosis, or Charcot disease but without a definitive diagnosis. The cause and natural history of RDO are unclear, but total hip arthroplasty has been utilized as a treatment modality due to the severity of the symptoms. We reviewed retrospectively the records of total hip arthroplasties performed between 1990 and 2003 and identified ten hips in eight patients who fit the profile of the diagnosis of RDO. The mean age at time of surgery was 70. Nine hips were treated with total hip arthroplasty with a hybrid configuration; one hip was treated with a non-cemented total hip arthroplasty. Average follow-up was 6 years with no radiographic evidence of acetabular loosening or osteolysis and no evidence of asymmetric cup wear. One femoral component had evidence of loosening but has not been revised. RDO is an idiopathic condition with no single diagnostic laboratory, pathological, or radiographic finding. A complete preoperative work-up for other causes of hip disease prior to arthroplasty for suspected RDO is necessary to rule out treatable disease. Our series of patients with RDO responded well to hybrid and non-cemented total hip arthroplasty with good clinical and radiographic results.
Influence of Matrix Polarity on the Properties of Ethylene Vinyl Acetate–Carbon Nanofiller Nanocomposites
Authors: George Jinu Jacob , Bhowmick Anil K.
Published: March 2009

A series of ethylene vinyl acetate (EVA) nanocomposites using four kinds of EVA with 40, 50, 60, and 70 wt% vinyl acetate (VA) contents and three different carbon-based nanofillers—expanded graphite (EG), multi-walled carbon nanotube (MWCNT), and carbon nanofiber (CNF) have been prepared via solution blending. The influence of the matrix polarity and the nature of nanofillers on the morphology and properties of EVA nanocomposites have been investigated. It is observed that the sample with lowest vinyl acetate content exhibits highest mechanical properties. However, the enhancement in mechanical properties with the incorporation of various nanofillers is the highest for EVA with high VA content. This trend has been followed in both dynamic mechanical properties and thermal conductivity of the nanocomposites. EVA copolymer undergoes a transition from partial to complete amorphousness between 40 and 50 wt% VA content, and this changes the dispersion of the nanofillers. The high VA-containing polymers show more affinity toward fillers due to the large free volume available and allow easy dispersion of nanofillers in the amorphous rubbery phase, as confirmed from the morphological studies. The thermal stability of the nanocomposites is also influenced by the type of nanofiller.
Downregulation of CD2‐associated protein impaired the physiological functions of podocytes
Authors: Zhang Chun , Jiang Hua‐Jun , Chang Ying , Fang Zhan , Sun Xi‐Feng , Liu Jian‐She , Deng An‐Guo , Zhu Zhong‐Hua
Published: March 2009

Emerging evidences show that CD2‐associated protein (CD2AP) is involved in podocyte injury and the pathogenesis of proteinuria. However, the exact molecular mechanism by which CD2AP exerts its biological function is elusive. We knocked down CD2AP gene by target siRNA in conditionally immortalized mouse podocytes, which showed lowered cell adhesion and spreading ability (P < 0.05). At the same time, cell cycle was arrested in G2/M phase (P < 0.05), and pathologic nuclear division could easily be seen in CD2AP siRNA‐transfected podocytes. The proliferation of podocytes were also inhibited significantly by CD2AP siRNA transfection (P < 0.05). Further study revealed disordered distributions of F‐actin, as well as lowered nephrin expression and phosphorylation in podocytes. These data suggest that CD2AP may play a crucial role in maintaining the normal function of podocytes and lowered CD2AP causes podocyte injury by disrupting the cytoskeleton and disturbing the nephrin‐CD2AP signaling pathway.
Interaction between Sox proteins of two physiologically distinct bacteria and a new protein involved in thiosulfate oxidation
Authors: Welte Cornelia , Hafner Swetlana , Krätzer Christian , Quentmeier Armin , Friedrich Cornelius G. , Dahl Christiane
Published: March 2009

Organisms using the thiosulfate‐oxidizing Sox enzyme system fall into two groups: group 1 forms sulfur globules as intermediates (Allochromatium vinosum), group 2 does not (Paracoccus pantotrophus). While several components of their Sox systems are quite similar, i.e. the proteins SoxXA, SoxYZ and SoxB, they differ by Sox(CD)2 which is absent in sulfur globule‐forming organisms. Still, the respective enzymes are partly exchangeable in vitro: P. pantotrophus Sox enzymes work productively with A. vinosum SoxYZ whereas A. vinosum SoxB does not cooperate with the P. pantotrophus enzymes. Furthermore, A. vinosum SoxL, a rhodanese‐like protein encoded immediately downstream of soxXAK, appears to play an important role in recycling SoxYZ as it increases thiosulfate depletion velocity in vitro without increasing the electron yield.
Micellar lipid composition profoundly affects LXR‐dependent cholesterol transport across CaCo2 cells
Authors: Petruzzelli Michele , Groen Albert K. , van Erpecum Karel J. , Vrins Carlos , van der Velde Astrid E. , Portincasa Piero , Palasciano Giuseppe , van Berge Henegouwen Gerard P. , Sasso Giuseppe Lo , Morgano Annalisa , Moschetta Antonio
Published: March 2009

Intraluminal phospholipids affect micellar solubilization and absorption of cholesterol. We here study cholesterol transport from taurocholate–phospholipid–cholesterol micelles to CaCo2 cells, and associated effects on ABC‐A1 mediated cholesterol efflux. Micellar incorporation of egg‐yolk‐phosphatidylcholine markedly increased apical retention of the sterol with decreased expression of ABC‐A1, an effect that is prevented by synthetic liver X receptor (LXR) or retinoid X receptor (RXR) agonists. On the other hand, incorporation of lyso‐phosphatidylcholine (LysoPC) increased ABC‐A1–HDL‐dependent basolateral cholesterol efflux, an effect that is abated when LXR is silenced. Thus, the modulation of cholesterol metabolism via intraluminal phospholipids is related to the activity of the oxysterol nuclear receptor LXR.
The N‐terminal fragment of Reelin is generated after endocytosis and released through the pathway regulated by Rab11
Authors: Hibi Terumasa , Hattori Mitsuharu
Published: March 2009

Reelin is a large secreted glycoprotein essential for brain formation, but its trafficking and function at the molecular level remain incompletely understood. After binding to its receptor, Reelin is internalized by endocytosis. Here we show that internalized Reelin is subject to specific proteolysis within the cell and its N‐terminal fragment is re‐secreted. This re‐secretion is inhibited by bafilomycin A1 or by expression of a mutant of Rab11, a regulator of the recycling pathway. As the N‐terminal fragment does not bind to Reelin receptor but has homology to F‐spondin, its recycling may be involved in the regulation of extracellular matrix.
Rehabilitation Interventions in Parkinson Disease
Authors: Moroz Alex , Edgley Steven R. , Lew Henry L. , Chae John , Lombard Lisa A. , Reddy Cara Camiolo , Robinson Keith M.
Published: March 2009

Objective

This self‐directed learning module provides an evidence‐based update of exercise‐based rehabilitation interventions to treat Parkinson disease (PD). It is part of the study guide on stroke and neurodegenerative disorders in the Self‐Directed Physiatric Education Program for practitioners and trainees in physical medicine and rehabilitation. This focused review emphasizes treatment of locomotion deficits, upper limb motor control deficits, and hypokinetic dysarthria. New dopaminergic agents and deep brain stimulation are facilitating longer periods of functional stability for patients with PD. Adjunctive exercise‐based treatments can therefore be applied over longer periods of time to optimize function before inevitable decline from this neurodegenerative disease. As function deteriorates in patients with PD, the role of caregivers becomes more critical, thus training caregivers is of paramount importance to help maintain a safe environment and limit caregiver anxiety and depression. The overall goal of this article is to enhance the learner's existing practice techniques used to treat PD through exercise‐based intervention methods.
“Heading for the Gun”: Skills and Sophistication in an African Guerrilla War
Authors: White Luise
Published: March 2009

For much of the last seventy-five years African combatants, especially in wars of their own making, have not been seen as masters of the guns they shoot. In Kenya in the 1950s, for example, captured Mau Mau were humiliated: they were taken to shooting ranges where they failed to hit a target with their guns. More recently, rebels in southern Sudan considered guns poor, if effective substitutes for more embodied weapons like spears, while young men in Sierra Leone fought with the weapons at hand such as knives or machetes, because they were too poor to obtain guns. When the armies of Ethiopia and Eritrea fought well and hard with sophisticated weapons, it was said to be the result of Cold War rivalries or national agendas gone berserk. Rhodesia's bush war, Zimbabweans' liberation struggle, suggests something else, a space shaped by technology and clientelism in which guns, most especially guns in guerrilla hands, exemplify very specific European ideas about Africans, that they are skilled and sophisticated.
“The Armenian Question Is Finally Closed”: Mass Conversions of Armenians in Anatolia during the Hamidian Massacres of 1895–1897
Authors: Deringil Selim
Published: March 2009

Few issues in late-nineteenth-century Armenian/Turkish history straddle so many of the “questions” of the period as does the mass conversion of Armenians in the 1890s. The topic is enmeshed in the much-contested “Armenian Question,” the birth of Armenian nationalism, the so-called “Eastern Question,” and the rise of Turkish nationalism. This article will deal with these conversions by situating them within the larger context of the “Armenian Question” generally. Although important research has been done on the mass conversions during the genocide of 1915, surprisingly little has focused on the massacres of 1894–1897. Even more surprising is the lack of research to date into the issue of mass conversions during the latter period, and nothing has been written based on Ottoman archives. My aim here is to make a contribution towards filling this lacuna.
‘Regions’ and their study: wherefrom, what for and whereto?
Authors: FAWN RICK
Published: March 2009

Long a focal point in the study of Geography, regions have become a major concern of International Relations, and for some even its essence. Principle definitions and approaches, however, remain contested, as do the contexts in which and how they matter, from economic to security. This article examines contested views on what constitutes a region and on the nature and functioning of regional architecture, drawing from thematic and case-specific literature to indicate the expanse of analytical enquiry. These include the roles and interpretations of geography, identity, culture, institutionalisation, and the role of actors, including a hegemon, major regional powers and others actors from within a region, both state and societal. A final section indicates additional areas for future research.
Feasibility of new laser fusion by intense laser field
Authors: Imasaki K. , Li D.
Published: March 2009

A feasibility of a new approach of laser fusion in plasma without implosion has been proposed and discussed using an intense laser. The cross-section of nuclear reaction is increased by the enhanced penetrability of nuclei through the Coulomb barrier. In this approach, an intense laser field of more than 10 EW was required to distort the Coulomb barrier to obtain enough penetrability. In the new improved model, a nuclear potential with meson attractive force is considered. Enhancement is observed for penetrability around EW or less power laser due to a nuclear potential. Energy gain even with Deuterium-Deuterium reaction can be obtained on this scheme in Deuterium plasma with energetic nucleon theoretically.
JUSTICE AS A NATURAL PHENOMENON
Authors: Binmore Ken
Published: March 2009

This article is my latest attempt to come up with a minimal version of my evolutionary theory of fairness, previously summarized in my book Natural Justice. The naturalism that I espouse is currently unpopular, but Figure 1 shows that the scientific tradition in moral philosophy nevertheless has a long and distinguished history. John Mackie's Inventing Right and Wrong is the most eloquent expression of the case for naturalism in modern times. Mackie's demolition of the claims made for a priori reasoning in moral philosophy seem unanswerable to me.
DOES SEEING RED REQUIRE THINKING ABOUT RED THINGS?
Authors: Toribio Josefa
Published: March 2009

We continuously form perceptual beliefs about the world based on how things appear to us in our perceptual experiences. I see that the ripe tomato in front of me is red and I form the belief that this tomato is red based on my seeing it, i.e. based on my veridical perceptual experience of this red tomato. Perceptual experiences and beliefs are representational mental states. Both are defined not by what they are, i.e. their physical properties, but by what they are about, what they represent, by their content. The content of both perceptual experiences and beliefs is specified by how the world must be for them to represent things correctly; it is specified by stating the conditions under which they would be true.
MOVING BEYOND SECULARIST/RELIGIOUS APARTHEID? – A COMMENT FOLLOWING PAUL KURTZ'S ARTICLE ‘MORALITY IS NATURAL’
Authors: Watson Brenda
Published: March 2009

Paul Kurtz's article ‘Morality is natural’ in THINK 15 was most stimulating. It left me, however, somewhat dissatisfied. Whilst he is clearly right that that there is a fund of moral wisdom that has been developed by humankind, I question whether distancing morality from religion is the important priority for us today.
The nature and future of comparative politics
Authors: Schmitter Philippe C.
Published: March 2009

The future of comparative politics is in doubt. This sub-discipline of political science currently faces a ‘crossroads’ that will determine its nature and role. In this essay, I make a (willfully distorted) plea that it should eschew the alternative of continuing to follow one or another versions of ‘institutionalism’ or that of opting completely for ‘simplification’ based on rational choice. It should embrace the ‘complex interdependence’ of the contemporary political universe and adjust its selection of cases and concepts accordingly. Without pretending to offer a novel paradigm or method. I explore some of the implications of conducting comparative research in this more contingent and less predictable context.
Geographically targeted spending: exploring the electoral strategies of incumbent governments
Authors: Tavits Margit
Published: March 2009

Pork-barrel politics is traditionally associated with presidentialism, strong parties, candidate-centered elections, and/or developing democracies. This paper argues that vote-purchasing behavior by incumbent governments analogous to pork-barreling is likely to be universal. This paper develops a rationale according to which incumbent governments use their partisan ties to lower levels of government to pork-barrel effectively. This argument is tested and corroborated with original data on local government grant allocation from four Nordic countries – traditionally considered to be systems that are least prone to localism. Furthermore, the study also provides preliminary evidence that pork-barreling by incumbent governments is electorally rewarded and thereby a fully rational electoral strategy.
Political representation and the normative logic of two-level games
Authors: Savage Deborah , Weale Albert
Published: March 2009

This paper develops the normative logic of two-level games linking international negotiation and domestic acceptability. The kernel of the logic is to be found in the claim that normatively governed relations involve agents simultaneously asking whether the expectations that they have under an agreement are reasonable given the expectations of others under that agreement. This normative logic mirrors the empirical logic that Putnam (1988) identified in his seminal account.

The normative logic is derived from a consideration of relevant concepts of representation, and in particular the concepts of authorization in international negotiation and accountability in domestic ratification. Rawls’ (1996) distinction between the reasonable and the rational is then deployed to state normative conditions of domestic acceptability as well as the obligations of fairness that states owe to one another. Two implications for democratic theory are drawn.
Soil organic nitrogen mineralization across a global latitudinal gradient
Authors: Jones D. L. , Kielland K. , Sinclair F. L. , Dahlgren R. A. , Newsham K. K. , Farrar J. F. , Murphy D. V.
Published: March 2009

Understanding and accurately predicting the fate of carbon and nitrogen in the terrestrial biosphere remains a central goal in ecosystem science. Amino acids represent a key pool of C and N in soil, and their availability to plants and microorganisms has been implicated as a major driver in regulating ecosystem functioning. Because of potential differences in biological diversity and litter quality, it has been thought that soils from different latitudes and plant communities may possess intrinsically different capacities to perform key functions such as the turnover of amino acids. In this study we measured the soil solution concentration and microbial mineralization of amino acids in soils collected from 40 latitudinal points from the Arctic through to Antarctica. Our results showed that soil solution amino acid concentrations were relatively similar between sites and not strongly related to latitude. In addition, when constraints of temperature and moisture were removed, we demonstrate that soils worldwide possess a similar innate capacity to rapidly mineralize amino acids. Similarly, we show that the internal partitioning of amino acid‐C into catabolic and anabolic processes is conservative in microbial communities and independent of global position. This supports the view that the conversion of high molecular weight (MW) organic matter to low MW compounds is the rate limiting step in organic matter breakdown in most ecosystems.
Multilayered structures in the ionosphere F2 region and impulse‐like increase of the nightglow red 630 nm line intensity as a result of influence of shear excited atmospheric vortical perturbations
Authors: Didebulidze G. G. , Lomidze L. N. , Gudadze N. B. , Todua M.
Published: March 2009

It is shown that the formation of multilayered structures in the midlatitude ionosphere F2 layer can be caused by atmospheric vortical perturbation (shear wave) evolving in the meridional wind with linear zonal shear and can be accompanied by an impulse‐like increase (with duration about 1–3 h) in the red 630 nm line total nightglow intensity. The shear wave can produce an enhancement of the northward wind (or decrease in the southward one), which can cause a downward motion of the F2 layer peak height resulting in the impulse‐like increase in the red line intensity. An important increase in the red line intensity occurs until the appearance of the secondary peak below the F2 layer main peak close to the luminous layer. The observed impulse‐like increase of the red line intensity followed by oscillations characteristic of short‐period atmospheric gravity waves (AGWs) is considered as a possible result of transformation of shear excited three‐dimensional vortical perturbation (shear wave) into AGW. The possibility of the appearance of the multilayered structure in the ionosphere F2 region and the impulse‐like increase in the red line intensity under the influence of shear excited waves with vertical wave number kz ≠ 0 is demonstrated analytically and numerically.
Transient auroral features at Saturn: Signatures of energetic particle injections in the magnetosphere
Authors: Radioti A. , Grodent D. , Gérard J.‐C. , Roussos E. , Paranicas C. , Bonfond B. , Mitchell D. G. , Krupp N. , Krimigis S. , Clarke J. T.
Published: March 2009

We report for the first time transient isolated auroral spots at Saturn's southern polar region, based on Hubble Space Telescope (HST) FUV images. The spots last several minutes and appear distinct from the rest of the auroral emissions. We study two sets of HST and Cassini observations during which Cassini instrumentation detected signatures of energetic particle injections close to the region where, on the same day, HST observed transient auroral spots. On the basis of the simultaneous remote and in situ observations, we discuss the possibility that the transient features are associated with the dynamical processes taking place in the Kronian magnetosphere. Given the limitations in the available observations, we suggest the following possible explanations for the transient aurora. The injection region could directly be coupled to Saturn's ionosphere by pitch angle diffusion and electron scattering by whistler waves, or by the electric current flowing along the boundary of the injected cloud. The energy contained in the injection region indicates that electron scattering could account for the transient aurora process.
An analysis of shear waves generated by the Sterling explosion
Authors: Xu Heming , Stevens Jeffry L. , Baker G. Eli
Published: March 2009

We show that the near‐field shear waves from the decoupled explosion Sterling were likely caused by the cavity shape, which was approximately spherical except for a flat floor due to melted and recrystallized salt. We model the impact of the explosion shock wave on the cavity walls using a two‐dimensional (2‐D) Eulerian finite difference code that simulates the evolution of the air shock in the cavity coupled with 2‐D Lagrangian finite difference code that simulates the nonlinear region outside the cavity. Calculated shear waves generated by the asymmetric impact of the shock wave on the cavity walls match the observed initial shear wave amplitudes and radiation pattern. The observations also have substantial P and S coda, which are not reproduced by the calculations. Similarity of coda waveforms with distance indicates that their source is at or very near the cavity. Longer time modeling of the air shock evolution appears to produce a more realistic source function and provide a better match to the coda and indicates that the coda are caused by air reverberations between the top and bottom of the cavity. We assess the likelihood that fractures created by the tamped explosion that formed the cavity Salmon were reopened by Sterling. Modeling of hydrofracture propagation driven by the Sterling explosion, by coupling stress wave dynamics in rock with fluid mechanics in the fractures, shows that the cavity pressure is insufficient to overcome the overburden to propagate fractures into rock, except for the area immediately below the explosion on the cavity floor.
Coupled IMPACT aerosol and NCAR CAM3 model: Evaluation of predicted aerosol number and size distribution
Authors: Wang Minghuai , Penner Joyce E. , Liu Xiaohong
Published: March 2009

Simulated aerosol fields from a coupled aerosol/atmospheric circulation model that includes prediction of both sulfate aerosol size and number are evaluated. Sensitivity tests are used to evaluate uncertainties due to the inclusion of primary emitted particulate sulfate as a means of representing nucleation of particles in subgrid‐scale plumes, the use of two boundary layer aerosol nucleation mechanisms, and a three‐mode sulfate aerosol representation. Simulated annual and global aerosol budgets are comparable to other model studies with the exception of carbonaceous aerosols and fine mode dust, where smaller mass concentrations are simulated. The model underestimates the accumulation mode aerosol number in the marine boundary layer over middle and low latitudes, which is consistent with an underestimate of fine mode sea salt mass in these locations. Primary emitted particulate sulfate contributes significantly to aerosol number at sites located in the boundary layer over Europe, but the absence of constraints on the number of such particles from either observations or fine‐resolution models makes this treatment undesirable. Boundary layer nucleation mechanisms improve the comparison of simulated aerosol number concentrations with observations in the marine boundary layer, suggesting that a treatment of boundary layer nucleation is needed in global aerosol models, although more studies are needed to quantify how different nucleation mechanisms and condensable gases other than sulfuric acid affect aerosol number. The three‐mode representation of sulfate aerosol simulates the observed increase in accumulation mode number concentration with altitude in the upper troposphere and improves the simulated Aitken mode aerosol number concentration there. This indicates the importance of a separate representation of freshly nucleated particles when nucleation is an important source of particle number concentrations.
RANBP2 is an allosteric activator of the conventional kinesin‐1 motor protein, KIF5B, in a minimal cell‐free system
Authors: Cho Kyoung‐in , Yi Haiqing , Desai Ria , Hand Arthur R , Haas Arthur L , Ferreira Paulo A
Published: March 2009

The association of cargoes to kinesins is thought to promote kinesin activation, yet the validation of such a model with native cargoes is lacking because none is known to activate kinesins directly in an in vitro system of purified components. The RAN‐binding protein 2 (RANBP2), through its kinesin‐binding domain (KBD), associates in vivo with kinesin‐1, KIF5B/KIF5C. Here, we show that KBD and its flanking domains, RAN GTPase‐binding domains 2 and 3 (RBD2/RBD3), activate the ATPase activity of KIF5B approximately 30‐fold in the presence of microtubules and ATP. The activation kinetics of KIF5B by RANBP2 is biphasic and highly cooperative. Deletion of one of its RBDs lowers the activation of KIF5B threefold and abolishes cooperativity. Remarkably, RBD2–KBD–RBD3 induces unfolding and modest activation of KIF5B in the absence of microtubules. Hence, RANBP2 is the first native and positive allosteric activator known to jump‐start and boost directly the activity of a kinesin.
Opening the Black Box: A Multi-Method Analysis of An Enterprise Resource Planning Implementation
Authors: Shepherd Craig , Clegg Chris , Stride Chris
Published: March 2009

This paper presents a multi-method analysis of the implementation of an enterprise resource planning system. It argues the majority of research treats these systems as having essential technical properties that enable them to bring about positive organisational effects. In contrast, we adopt a post-essentialist perspective that understands discourse as constructing ERP systems, rather than reflecting their essential properties. Discourse analysis of interviews and focus groups was used to compare justifications for the implementation produced by members of the ERP project team with end users’ reactions to the system. In contrast to previous studies, this opens the ERP black box by illustrating how the capabilities of these systems, and their organisational effects, are constructed through language. Moreover, it demonstrates the important function these constructions perform in legitimising or undermining ERP implementation. Statistical analysis of post-implementation questionnaires identified the predictors of established measures of users’ reactions to IT systems. By comparing these data with end users’ discursive reactions to the project, we identify several constructs for inclusion in future studies of users’ reactions to ERP systems. The paper concludes by summarising the contributions and limitations of the study and its implications for future research and practice.
Sponsorship and it Vendor Management of Projects
Authors: Liu Li , Yetton Philip
Published: March 2009

Project sponsorship is assumed to be critical to the success of information systems development and implementation. However, there is limited research on the effect of vendor-based sponsorship on the management of information technology (IT) projects. This paper contributes to that emerging body of evidence. Drawing on literature on psychological contract, management control and project sponsorship, the authors propose that vendor-based sponsors influence project performance in two main ways. One is to protect project quality by renegotiating contract with the client; and the other is to resource the project. Based on a survey of senior managers in IT services vendor organisations, it reports that project sponsorship improves the quality, but not the cost or timeliness, of vendor delivery of IT projects. The findings suggest that IT services vendors can improve their project delivery capability by appointing project sponsors.
Influence of miscut on the anisotropic magnetoresistance of magnetite thin films
Authors: Ramos R. , Arora S. K. , Shvets I. V.
Published: March 2009

We present the comparative measurements of the angular dependence of the anisotropic magnetoresistance (AMR) of magnetite (Fe3O4) films on MgO(001) nonvicinal and vicinal substrates (2.86° miscut along the ⟨100⟩ direction). The AMR behavior for current parallel and perpendicular to the direction of step edges is quite similar to that of nonvicinal Fe3O4 films for temperatures above the Verwey transition (TV). However, we observed a dramatic change in the symmetry of the AMR’s angular response below TV for the vicinal sample, which depends on the direction of current with respect to the step edges. The results highlight the influence of step edge induced spin disorder on the transport properties below Verwey transition.
Thermal insulator design for optimizing the efficiency of thermal flying height control sliders
Authors: Li Hui , Yin Chia-Ti , Talke Frank E.
Published: March 2009

This paper is concerned with the optimization of the location and size of thermal flying height control (TFC) elements in magnetic recording sliders. It investigated the performance of a so-called thermal insulator positioned adjacent to the heater to control the temperature distribution inside the slider. A parametric study of the thermal conductivity, thickness, and location of the thermal insulator was performed to improve the thermal actuation and thermal efficiency. Optimization of the dimensions and properties of a thermal insulator was found to achieve a substantial reduction in the flying height of the read/write elements. In addition, the magnitude of the thermal actuation was found to increase.
Effects of laminated soft layer on magnetization reversal of exchange coupled composite media
Authors: Hou Hao-Cheng , Lin Meng-Shian , Liao Jung-Wei , Wu Tzung-Lin , Lai Chih-Huang , Chen Rong-Zhi , Lee Jye-Long , Lin Hong-Ji , Chang Fan-Hsiu , Yang Jyh-Shinn
Published: March 2009

The laminated soft layer (LSL) that comprises the granular [CoPtCr–SiO2/Pt]N multilayers with perpendicular magnetization is designed to reduce the switching field of exchange coupled composite (ECC) media. The magnetic simulation shows that the reduction in the switching field can be optimized by changing the coupling strength between the adjacent CoPtCr–SiO2 layers in LSL. The reversal mechanism of ECC media with LSL depends on the bilayers number N of [CoPtCr–SiO2/Pt]N. Both simulation and experiments reveal that the domain-wall assisting reversal strongly depends on the thickness of LSL. By properly adjusting the coupling strength inside the LSL, the switching and saturation fields can be significantly reduced at a limited thickness of the soft layer due to decreased domain-wall length by the Pt lamination.
Use of patterned magnetic films to retain and orient micro-components during fluidic assembly
Authors: Cheng D. I. , Rumpler J. J. , Perkins J. M. , Zahn M. , Fonstad C. G. , Cramer E. S. , Zuneska R. W. , Cadieu F. J.
Published: March 2009

Patterned magnetic thin films have for the first time been used to orient and retain micron-sized III-V elements on silicon substrates during fluidic hybrid assembly. Modeling of the forces between Ni thin films patterned on one surface of 5–6 μm target areas on Si substrates predicts that the strength and fall-off characteristics of the attractive forces can be engineered to orient and securely retain only pills that are right side up. Verification of this behavior has been obtained by assembling 50×100 μm2 micropills in recesses with patterns of Sm-Co rectangles.
Interaction between buoyancy and diffusion-driven instabilities of propagating autocatalytic reaction fronts. I. Linear stability analysis
Authors: D’Hernoncourt J. , Merkin J. H. , De Wit A.
Published: March 2009

The interaction between buoyancy-driven and diffusion-driven instabilities that can develop along a propagating reaction front is discussed for a system based on an autocatalytic reaction. Twelve different cases are possible depending on whether the front is ascending or descending in the gravity field, whether the reactant is heavier or lighter than the products, and whether the reactant diffuses faster, slower, or at the same rate as the product. A linear stability analysis (LSA) is undertaken, in which dispersion curves (plots of the growth rate σ against wave number k) are derived for representative cases as well as an asymptotic analysis for small wave numbers. The results from the LSA indicate that, when the initial reactant is denser than the reaction products, upward propagating fronts remain unstable with the diffusion-driven instability enhancing this instability. Buoyantly stable downward propagating fronts become unstable when the system is also diffusionally unstable. When the initial reactant is lighter than the reaction products, any diffusionally unstable upward propagating front is stabilized by small buoyancy effects. A diffusional instability enhances the buoyant instability of a downward propagating front with there being a very strong interaction between these effects in this case.
Evaluation of an electromagnetic microactuator using scanning Hall probe microscopy measurements
Authors: Dinulovic Dragan , Saalfeld Henry , Celinski Zbigniew , Field Stuart B. , Gatzen Hans H.
Published: March 2009

Scanning Hall probe microscopy (SHPM) was used to evaluate integrated magnetic microactuators designed for hard disk drives. The Hall probe measurements of the generated magnetic field strength as a function of the applied current or distance were compared to results of a finite element method simulation. The SHPM measurements and simulation results are in good agreement, confirming that simulations supported by SHPM measurements can be used successfully to predict the performance of microactuators.
Influence of phonons on the temperature dependence of photoluminescence in InN with low carrier concentration
Authors: Holtz M. E. , Gherasoiu I. , Kuryatkov V. , Nikishin S. A. , Bernussi A. A. , Holtz M. W.
Published: March 2009

We report the temperature dependence of photoluminescence (PL) spectra for InN. For a free-carrier concentration n=5.9×1017 cm−3 and low temperature, the main PL band is observed at 0.669 eV. The PL shift and broadening are described from 20 to 300 K based on electron-phonon interactions. Two discrete phonon sidebands (PSBs) are observed with corresponding phonon energy of ∼69 meV. The PSB temperature shift and linewidth broadening are well described by previous theory.
Thermoelectric properties in nanostructured homologous series alloys GamSbnTe1.5(m+n)
Authors: Cui Jiaolin , Liu Xianglian , Yang Wei , Chen Dongyong , Fu Hong , Ying Pengzhan
Published: March 2009

In this paper we reported the thermoelectric (TE) properties in nanostructured homologous series alloys GamSbnTe1.5(m+n) over the temperature range of 318–482 K and observed the maximum TE figure of merit (ZT) value of 0.98 for the alloy with m:n=1:10 at 482 K, which is approximately 0.24 higher than that of undoped Sb2Te3 at the corresponding temperature. This improvement is mainly attributed to the substantial reduction in lattice thermal conductivity due to the phonon scattering caused partly by the nanograins (<30 nm) and amorphous structure conceived in the matrix and partly by the lattice distortion resulted from an occupation of some Ga atoms in the Sb sites and a certain amount of Ga2Te3 precipitation. If in comparison with the TE properties for Ga directly doped Bi–Sb–Te solid solutions, we conclude that these Bi-free nanostructured homologous series alloys GamSbnTe1.5(m+n) with proper compositions are of great potentiality for the improvement of TE performance.
Effects of particle properties on segregation-band drift in particle-laden rimming flow
Authors: Guyez E. , Thomas P. J.
Published: March 2009

We experimentally study rimming flow of a particle-laden fluid. We begin to investigate the details of the spatiotemporal segregation-band dynamics that were first documented by us elsewhere [E. Guyez and P. J. Thomas, Phys. Rev. Lett. 100, 074501 (2008)]. There exist eight relevant nondimensional parameters that must be expected to affect the drift dynamics of segregation bands in particle-laden rimming flow. Here we summarize results from experiments investigating the effects of three of these parameters that involve the particle size and the particle density. It is shown that two of the parameters are crucial to the initiation of the band drift and that bands become stationary whenever either one of the two parameters adopts values below an associated critical threshold. Based on the physical relevance of the two parameters it is concluded that the initiation of band drift is strongly affected by a competition between capillary forces and gravitational forces. The third nondimensional parameter studied here characterizes the bulk particle concentration and it is found that it controls the band-drift speed in the parameter regime where band drift exists.
A universal magnification theorem for higher-order caustic singularities
Authors: Aazami A. B. , Petters A. O.
Published: March 2009

We prove that, independent of the choice of a lens model, the total signed magnification always sums to zero for a source anywhere in the four-image region close to swallowtail, elliptic umbilic, and hyperbolic umbilic caustics. This is a more global and higher-order analog of the well-known fold and cusp magnification relations, in which the total signed magnifications in the two-image region of the fold and the three-image region of the cusp are both always zero. As an application, we construct a lensing observable for the hyperbolic umbilic magnification relation and compare it with the corresponding observables for the cusp and fold relations using a singular isothermal ellipsoid lens. We demonstrate the greater generality of the hyperbolic umbilic magnification relation by showing how it applies to the fold image doublets and cusp image triplets and extends to image configurations that are neither. We show that the results are applicable to the study of substructure on galactic scales using observed quadruple images of lensed quasars. The magnification relations are also proven for generic one-parameter families of mappings between planes, extending their potential range of applicability beyond lensing.
Quantum calculations of H2–H2 collisions: From ultracold to thermal energies
Authors: Quéméner Goulven , Balakrishnan Naduvalath
Published: March 2009

We present quantum dynamics of collisions between two para-H2 molecules from low (10−3 K) to high collision energies (1 eV). The calculations are carried out using a quantum scattering code that solves the time-independent Schrödinger equation in its full dimensionality without any decoupling approximations. The six-dimensional potential energy surface for the H4 system developed by Boothroyd et al. [J. Chem. Phys. 116, 666 (2002)] is used in the calculations. Elastic, inelastic, and state-to-state cross sections as well as rate coefficients from T=1 K to 400 K obtained from our calculations are compared with available experimental and theoretical results. Overall, good agreement is obtained with previous studies.
Eigenvalue separation in some random matrix models
Authors: Bassler K. E. , Forrester P. J. , Frankel N. E.
Published: March 2009

The eigenvalue density for members of the Gaussian orthogonal and unitary ensembles follows the Wigner semicircle law. If the Gaussian entries are all shifted by a constant amount s/(2N)1/2, where N is the size of the matrix, in the large N limit a single eigenvalue will separate from the support of the Wigner semicircle provided s>1. In this study, using an asymptotic analysis of the secular equation for the eigenvalue condition, we compare this effect to analogous effects occurring in general variance Wishart matrices and matrices from the shifted mean chiral ensemble. We undertake an analogous comparative study of eigenvalue separation properties when the sizes of the matrices are fixed and s→∞, and higher rank analogs of this setting. This is done using exact expressions for eigenvalue probability densities in terms of generalized hypergeometric functions and using the interpretation of the latter as a Green function in the Dyson Brownian motion model. For the shifted mean Gaussian unitary ensemble and its analogs, an alternative approach is to use exact expressions for the correlation functions in terms of classical orthogonal polynomials and associated multiple generalizations. By using these exact expressions to compute and plot the eigenvalue density, illustrations of the various eigenvalue separation effects are obtained.
Increased ferromagnetic resonance linewidth and exchange anisotropy in NiFe/FeMn bilayers
Authors: Yuan Shujuan , Kang Baojuan , Yu Liming , Cao Shixun , Zhao Xinluo
Published: March 2009

In the past investigations, the exchange-biased bilayers show much larger ferromagnetic resonance (FMR) linewidth than that of single ferromagnetic layer films. However, the mechanism of the large linewidth remains controversial. In this paper, the FMR linewidths of NiFe/FeMn bilayers prepared by dc magnetron sputtering system are systematically studied. Besides the intrinsic damping and magnetic inhomogeneity, the extrinsic relaxation based on two-magnon scattering process should be also considered to explain the strong in-plane angular dependence of the linewidths. The fitting of the out-of-plane angular dependence of the linewidths shows that the intrinsic Gilbert damping effect plays a major role in the increased linewidth in the bilayers. The value of the g factor increases due to the effect of the exchange coupling at the NiFe/FeMn interface, resulting in an enhancement in the Gilbert damping factor G. The fitting results indicate that the line broadening of the exchange-biased films is related to the exchange anisotropy. The effects of FeMn layer thickness, growth sequence of FeMn layer, and temperature on the linewidths further approve this interpretation.
Reliable electron-only devices and electron transport in n-type polymers
Authors: Steyrleuthner R. , Bange S. , Neher D.
Published: March 2009

Current-voltage analysis of single-carrier transport is a popular method for the determination of charge carrier mobilities in organic semiconductors. Although in widespread use for the analysis of hole transport, only a few reports can be found where the method was applied to electron transport. Here, we summarize the experimental difficulties related to the metal electrode leakage currents and nonlinear differential resistance (NDR) effects and explain their origin. We present a modified preparation technique for the metal electrodes and show that it significantly increases the reliability of such measurements. It allows to produce test devices with low leakage currents and without NDR even for thin organic layers. Metal oxides were often discussed as a possible cause of NDR. Our measurements on forcibly oxidized metal electrodes demonstrate that oxide layers are not exclusively responsible for NDR effects. We present electron transport data for two electron-conducting polymers often applied in all-polymer solar cells for a large variety of layer thicknesses and temperatures. The results can be explained by established exponential trapping models.