bluuebunny/crossref_metadata_2025 huggingface dataset:
Effect of the Healthy MOMs Lifestyle Intervention on Reducing Depressive Symptoms Among Pregnant Latinas
Authors: Kieffer Edith C. , Caldwell Cleopatra H. , Welmerink Diana B. , Welch Kathleen B. , Sinco Brandy R. , Guzmán J. Ricardo
Published: May 2012

Depression during the prenatal and postpartum periods is associated with poor maternal, perinatal and child outcomes. This study examines the effectiveness of a culturally and linguistically tailored, social support‐based, healthy lifestyle intervention led by trained community health workers in reducing depressive symptoms among pregnant and early postpartum Latinas. A sample of 275 pregnant Latinas was randomized to the Healthy MOMs Healthy Lifestyle Intervention (MOMs) or the Healthy Pregnancy Education (control) group. More than one‐third of participants were at risk for depression at baseline. MOMs participants were less likely than control group participants to be at risk for depression at follow‐up. Between baseline and 6 weeks postpartum, MOMs participants experienced a significant decline in depressive symptoms; control participants experienced a marginally significant decline. For MOMs participants, most of this decline occurred during the pregnancy intervention period, a time when no change occurred for control participants. The change in depressive symptoms during this period was greater among MOMs than control participants (“intervention effect”). From baseline to postpartum, there was a significant intervention effect among non‐English‐speaking women only. These findings provide evidence that a community‐planned, culturally tailored healthy lifestyle intervention led by community health workers can reduce depressive symptoms among pregnant, Spanish‐speaking Latinas.
Prenatal Treatment of Congenital Adrenal Hyperplasia—Not Standard of Care
Authors: Witchel Selma Feldman , Miller Walter L.
Published: May 2012

Congenital adrenal hyperplasia (CAH) due to steroid 21‐hydroxylase deficiency is a common autosomal recessive disorder due to mutations in the CYP21A2 gene. Since genetic counselors play a crucial role in educating families about inherited disorders, they need to have thorough knowledge regarding the pathophysiology of CAH especially the effects on the fetus, the complex genetics of this disorder, and the controversies surrounding experimental prenatal dexamethasone treatment. Affected female fetuses may have varying degree of virilization of the external genitalia. Starting in the 1980's, supraphysiologic glucocorticoid treatment was used to decrease the virilization of the external genitalia of affected female fetuses. However, recent clinical observations, animal studies and greater awareness of the details of human fetal adrenal physiology raise concerns regarding the safety of this prenatal treatment. We review the pathophysiology of CAH, the safety and ethical considerations of prenatal dexamethasone treatment and the views of multiple medical societies that conclude that this experimental therapy should only be done in prospective trials approved by ethical review boards.
Individualism and Community as Contested Rhetorics in the Catholic New Evangelization Movement
Authors: McCallion Michael J. , Bennett-Carpenter Benjamin , Maines David R.
Published: May 2012

This article addresses a new religious movement within one of the oldest ecclesiastical organizations in Christendom—the Catholic Church. The Catholic New Evangelization (NE) is an intra-ecclesial movement articulated and inspired by the late Pope John Paul II. Our analysis of this movement focuses on the emerging tensions between the contrasting individualist and communalist orientations of what we call “Vatican II Catholics” and “NE Catholics,” respectively. We examine responses to NE rhetoric and its implementation in the Catholic Archdiocese of Detroit's central services, the archdiocesan seminary, and two local Detroit parishes. At these sites, the NE rhetoric, especially in its emphasis on having a “personal relationship with Jesus,” has intensified individual versus community tensions among Catholic professionals and lay leaders in the Detroit area.
Retrospective case review of pyriform sinus fistulae of third branchial arch origin commonly presenting as acute suppurative thyroiditis in children
Authors: Yolmo D , Madana J , Kalaiarasi R , Gopalakrishnan S , Kiruba Shankar M , Krishnapriya S
Published: May 2012

Objective:

Abnormalities of the third branchial arch are less common than those of the second arch and usually present with left thyroid lobe inflammation. This paper describes 15 cases of pyriform sinus fistulae of third branchial arch origin usually presenting as recurrent thyroid abscess on the left side.

Method:

A retrospective review of 15 cases of third arch fistulae managed 2000 and 2008, diagnosed based on histopathology and radiological evidence of a fistulous tract, and treated with fistulectomy with left hemithyroidectomy.

Results:

All patients (six boys and nine girls, aged three to 15 years) presented with recurrent low neck inflammation. Pre-operative ultrasound, computed tomography fistulography and barium swallow demonstrated a third arch fistulous tract, left-sided in all cases. The fistula was detected intra-operatively and pathologically in all cases. Surgery (successful in all cases) emphasised complete recurrent laryngeal nerve and ipsilateral pyriform sinus exposure, to facilitate tract excision, with left hemithyroidectomy. There was no recurrence over three to five years' follow up.

Conclusion:

Paediatric recurrent low neck inflammatory episodes, due to thyroidal abscess, especially left-sided, should raise suspicion of pyriform sinus fistulae.
A method to determine the flux limiter via the motion of the M-band emission region in Au hohlraum
Authors: Zhao Yiqing , Lan Ke , Song Peng , Zheng Wudi , Li Xin
Published: May 2012

In this paper, the influence of the electron flux limiter fe on hohlraum plasmas is studied by using the two-dimensional code LARED-H, and a method to experimentally determine fe via the motion of the M-band emission region in Au hohlraum is proposed. From our simulations, the limited free streaming flux may dominates the heat conduction in the regions with steep temperature gradient, including the laser deposition region, the flux-heated overcritical region, and the laser channel boundary between the hot laser plasmas and the surrounding radiation ablated plasmas, while these are important X-ray emission regions. Hence, the choosing of fe may influence the wall plasma expansion and the laser spot motion, and further influence the motion of the emission regions. From our study, the motion of the M-band (>1.5 keV) emission region is sensitive to fe when the limited free streaming flux dominates the heat conduction of the wall plasma expansion region, and so it is possible to determine fe via the motion of the M-band emission region. In this work, the model used in our simulations is taken from the wall and laser spot motion experiments done by Huser et al. (2009).
Time evolution of solid-density plasma during and after irradiation by a short, intense laser pulse
Authors: Luan Shixia , Yu Wei , Murakami Masakatsu , Zhuo Hongbin , Yu Mingyang , Ma Guangjin , Mima Kunioki
Published: May 2012

A two-dimensional theoretical model for the evolution of solid-density plasma irradiated by short, intense laser pulse is introduced. The electrons near the target surface are pushed inward by the radiation pressure, leading to a receding electron density jump where the laser is reflected. The electrostatic field of the resulting charge separation eventually balances the radiation pressure at the laser peak. After that the charge separation field becomes dominant. It accelerates and compresses the ions that are left behind until they merge with the compressed electrons, resulting in a high-density plasma peak. The laser pulse reflected from the receding electron density jump loses energy in plasma and suffers Doppler frequency red-shift, which can provide valuable information on the laser absorption rate and the speed of the receding electrons. Electron oscillations, including theu × Boscillations across the density jump at twice the laser frequency during the laser action, as well as the low-frequency oscillations appearing after laser action, are identified.
Biped walking control using a trajectory library
Authors: Liu Chenggang , Atkeson Christopher G. , Su Jianbo
Published: May 2012

This paper presents biped walking control using a library of optimal trajectories. Biped walking control is formulated as an optimal control problem. We use a parametric trajectory optimization method to find the periodic steady-state walking trajectory. As a second stage, we use Differential Dynamic Programming to generate a library of optimal trajectories and locally linear models of the optimal control law, which are used to construct a more global control law. The proposed controller is compared with a trajectory tracking controller using optimal gains. The utility and performance of the proposed method are evaluated using simulated walking control of a planar five-link biped robot.
In Memoriam: David L. Waltz
Authors: Tait John
Published: May 2012

David L. Waltz died on March 22, 2012 after suffering from brain cancer.

Dave was a good friend to Natural Language Engineering, and provided some sage advice when Roberto Garigliano and I started working on the proposed journal in the early 1990s; he subsequently agreed to serve as a founding editorial board member.
MONETARY POLICY AND SUNSPOT FLUCTUATIONS IN THE UNITED STATES AND THE EURO AREA
Authors: Hirose Yasuo
Published: May 2012

We estimate a two-country open economy version of the New Keynesian dynamic stochastic general equilibrium model for the United States and the Euro area, using Bayesian techniques that allow for both determinacy and indeterminacy of the equilibrium. Empirical analysis shows that the worldwide equilibrium is indeterminate due to a passive monetary policy in the Euro area, even if U.S. policy is aggressive enough. We demonstrate that the impulse responses under indeterminacy exhibit dynamics different from those under determinacy and that sunspot shocks affect the Euro economy to a substantial degree, whereas the transmission of sunspots to the United States is limited.
INVESTMENT AND REAL EXCHANGE RATES IN STICKY PRICE MODELS
Authors: Martínez-García Enrique , Søndergaard Jens
Published: May 2012

This paper investigates how the inclusion of capital in the workhorse new open economy macro model affects its ability to generate volatile and persistent real exchange rates. We show that capital accumulation facilitates intertemporal consumption smoothing and significantly reduces the volatility of the real exchange rate. Nonetheless, monetary and investment-specific technology (IST) shocks still induce more real exchange rate volatility and less consumption comovement than productivity shocks (with or without capital). We find that endogenous persistence is particularly sensitive to the inertia of the monetary policy rule even with persistent exogenous shocks. However, irrespective of whether capital is present, productivity and IST shocks trigger highly persistent real exchange rates, whereas monetary shocks do not. Moreover, we point out that IST shocks tend to generate countercyclical real exchange rates—unlike productivity or monetary shocks—but have the counterfactual effect of also producing excessive investment volatility and countercyclical consumption.
“You Talk Of Terrible Things So Matter-of-Factly in This Language of Science”: Constructing Human Rights in the Academy
Authors: Carpenter Charli
Published: May 2012

How does the everyday politics behind scientific inquiry impact what we come to know about the world? Here I consider this question in the context of my own fieldwork on the human rights response to children born of war in Bosnia-Herzegovina. First, I reflect on how the academy functions to direct researchers' attention and skill sets to certain types of human rights problems in certain ways, inevitably affecting what we can know about our subject matter. Second, I consider the practical politics by which human rights scholars interface with policy-makers, the media, and the public, and the extent to which members of the human rights scholarly community constitute nodes in the wider networks we are studying.
Response to Monika Nalepa's Review of Overcoming Historical Injustices: Land Reconciliation in South Africa
Authors: Gibson James L.
Published: May 2012

First, I would like to declare how much I appreciate the opportunity to engage in this dialogue with Monika Nalepa. As I have said, her work on lustration constitutes a major contribution to our understanding of transitional justice processes.
Investigation of land ice‐ocean interaction with a fully coupled ice‐ocean model: 1. Model description and behavior
Authors: Goldberg D. N. , Little C. M. , Sergienko O. V. , Gnanadesikan A. , Hallberg R. , Oppenheimer M.
Published: May 2012

Antarctic ice shelves interact closely with the ocean cavities beneath them, with ice shelf geometry influencing ocean cavity circulation, and heat from the ocean driving changes in the ice shelves, as well as the grounded ice streams that feed them. We present a new coupled model of an ice stream‐ice shelf‐ocean system that is used to study this interaction. The model is capable of representing a moving grounding line and dynamically responding ocean circulation within the ice shelf cavity. Idealized experiments designed to investigate the response of the coupled system to instantaneous increases in ocean temperature show ice‐ocean system responses on multiple timescales. Melt rates and ice shelf basal slopes near the grounding line adjust in 1–2 years, and downstream advection of the resulting ice shelf thinning takes place on decadal timescales. Retreat of the grounding line and adjustment of grounded ice takes place on a much longer timescale, and the system takes several centuries to reach a new steady state. During this slow retreat, and in the absence of either an upward‐or downward‐sloping bed or long‐term trends in ocean heat content, the ice shelf and melt rates maintain a characteristic pattern relative to the grounding line.
Molecular Simulation in the Energy Biosciences
Authors: Cheng Xiaolin , Parks Jerry M. , Petridis Loukas , Lindner Benjamin , Schulz Roland , Guo Hao-Bo , Srinivas Goundla , Smith Jeremy C.
Published: May 2012

Molecular simulation can be used to understand key physical processes in the energy biosciences. Both molecular mechanical (MM) and quantum mechanical (QM) simulation techniques provide atomic-detailed insight into mechanisms at the core of research in bioenergy and bioremediation. The present article describes molecular simulation in the energy biosciences in two sections: Methods and Applications. In the Methods section, we provide a synopsis of current progress in developing simulation techniques that make efficient use of large-scale supercomputers. This is done with two examples: scalable implicit solvation models and scaling molecular dynamics (MD) to O(100k) cores. In the Applications section, we discuss modeling and simulation of cellulosic biomass, an effort aimed at shedding light on biomass recalcitrance to hydrolysis (a bottleneck in biofuel production) and simulations describing the fate of mercury in contaminated biogeochemical systems. We outline research aimed at understanding the dynamics and function of the proteins and enzymes that confer mercury resistance to bacteria.
Top-down Mesoscale Models and Free Energy Calculations of Multivalent Protein-Protein and Protein-Membrane Interactions in Nanocarrier Adhesion and Receptor Trafficking
Authors: Liu Jin , Agrawal Neeraj J. , Eckmann David M. , Ayyaswamy Portonovo S. , Radhakrishnan Ravi
Published: May 2012

In this chapter we present a summary of recent applications of top-down mesoscale modeling to two biologically relevant problems: (1) adhesion of nanocarriers to cells mediated by multivalent receptor-ligand interactions in targeted drug delivery; (2) internalization of cell surface receptors in cells via the biological process of endocytosis. In particular, we focus on methods for computing absolute/relative free energies using these mesoscale models in order to facilitate direct comparison with experimental data.
Studying Proteins and Peptides at Material Surfaces
Authors: Feng Jun , Lynch Gillian C. , Pettitt B. Montgomery
Published: May 2012

We review simulation and experiments using protein microarrays. Arrays of thousands of proteins with varied functionalities offer parallel, high throughput screening of molecular interactions. Immobilization of probe molecules to a surface or bead allows for location to be equated with identification. The inhomogeneity present because of the material surface can alter the thermodynamic and kinetic recognition properties of the proteins. Understanding the behavior of proteins at interfaces has implications in the design of protein microarrays as well as in the development of other interfacial biomolecular engineering technologies. In this review, we describe current problems when immobilizing peptides/proteins on material surfaces. The interface between experimental and simulation studies is discussed regarding orientation, and conformational stability on materials with varied surface chemistry in terms of protein-surface interactions.
Multiscale Design: From Theory to Practice
Authors: Fish J. , Filonova V. , Yuan Z.
Published: May 2012

We present a practical multiscale approach that possesses computational efficiency of phenomenological models for heterogeneous media with accuracy inherent to generalized and nonlocal continua models. The method introduces no scale separation, makes no assumption about infinitesimality of the fine-scale structure, does not require higher order continuity, introduces no new degrees-of-freedom, is free of higher order boundary conditions and exploits a pre-computed material database to effectively solve a unit cell (representative volume) problem. It features four building blocks: (i) the nonlocal quadrature scheme, (ii) the coarse-scale stress function, (iii) the residual-free fields and (iv) identification of the overall microstructural properties from the coarse-scale observations.
Opposites Attract: Shape and Electrostatic Complementarity in Protein-DNA Complexes
Authors: Harris Robert C. , Mackoy Travis , Dantas Machado Ana Carolina , Xu Darui , Rohs Remo , Fenley Marcia Oliveira
Published: May 2012

Proteins and DNA form complexes due to complementary properties of their molecular structure and electrostatic potential at the binding interface. While proteins predominantly consist of globular domains complemented by linkers and tails, DNA generally forms a double helix through hydrogen bonding between bases on opposite strands. Globular domains of DNA-binding proteins are condensed structures with little flexibility that often bind the major groove while protein linkers and tails are extremely flexible, which play a role for many protein families in binding the minor groove. Protein residues have been observed to recognize the sequence-dependent shape of DNA, engage in hydrogen bonding with the functional groups of the bases, form water-mediated hydrogen bonds, or be attracted by the negative electrostatic potential that surrounds DNA. Due to the polyanionic character of the double helix, basic side chains, such as arginines and lysines, are key protein residues involved in DNA binding. Much structural and biophysical knowledge on protein-DNA recognition has been gathered from experimental and computational studies, but the vast amount of DNA sequence information from genomic studies demonstrates that our understanding of the molecular origins of protein-DNA binding specificity, gene regulation, and chromatin organization is far from completion. The present book chapter offers a new perspective on protein-DNA binding, which emphasizes the need to consider shape and electrostatic complementarity together when rationalizing protein-DNA complex formation.
Speech-Language Pathology in the Peace Corps: Necessity and Sustainability
Authors: Pierce Melissa A.
Published: May 2012

In countries other than the United States, the study and practice of speech-language pathology is little known or nonexistent. Recognition of professionals in the field is minimal. Speech-language pathologists in countries where speech-language pathology is a widely recognized and respected profession often seek to share their expertise in places where little support is available for individuals with communication disorders. The Peace Corps offers a unique, long-term volunteer opportunity to people with a variety of backgrounds, including speech-language pathologists. Though Peace Corps programs do not specifically focus on speech-language pathology, many are easily adapted to the profession because they support populations of people with disabilities. This article describes how the needs of local children with communication disorders are readily addressed by a Special Education Peace Corps volunteer.
International Research Collaborations: The Process and Its Benefits
Authors: Abdalla Fauzia , Irani Farzan
Published: May 2012

With the increase in availability of social media and electronic communication mediums, it is now easier than ever to make contact and establish international research collaborations. There is a growing need to address issues related to the prevention, assessment, and intervention of communication impairments across culturally and linguistically diverse populations (Chiasson, 2007). This article provides a brief overview of the process of establishing and maintaining international research collaborations in the field of communication sciences and disorders. The article draws from personal experiences of the authors and survey-based responses from seven other professionals in the field who are actively involved in international collaborations. The authors address some common obstacles to international collaboration and provide insights to help make such relationships productive for all members. Finally, the authors provide a brief review of electronic communication mediums that can be used to increase efficiency and productivity of international collaborations.
Three-dimensional elemental mapping of hollow Fe2O3@SiO2 mesoporous spheres using scanning confocal electron microscopy
Authors: Wang Peng , Hashimoto Ayako , Takeguchi Masaki , Mitsuishi Kazutaka , Shimojo Masayuki , Zhu Yufang , Okuda Mitsuhiro , Kirkland Angus I. , Nellist Peter D.
Published: May 2012

Energy filtered scanning confocal electron microscopy (EFSCEM) in an aberration-corrected transmission electron microscope offers an approach for three-dimensional imaging and chemical analysis of nanoscale materials related to the well-established technique of confocal scanning optical microscopy. Here, we apply EFSCEM to the compositional analysis of the core structure in candidate structures for targeted drug delivery. Element-specific optical sectioning along the specimen depth direction demonstrates the presence of additional Si in a nominal Fe2O3 core. The presence of Si in the core is consistent with a specific formation mechanism for the hollow structure of the core.
Dual roles of doping and trapping of semiconductor defect levels and their ramification to thin film photovoltaics
Authors: Chin Ken K.
Published: May 2012

It is pointed out that the semiconductor localized intrinsic/impurity defect levels’ dual roles for carrier doping and trapping (Shockley-Read-Hall generation-recombination) have been treated differently and inconsistently. It is proposed that instead of ionization or activation energy, transition Gibbs free energy level should be used for the dual roles of doping-trapping. To qualitatively evaluate the effectiveness of doping and of trapping, the concept of doping efficacy ηd and two types of trapping efficacy ηt and ηSRH are proposed. The relationship of ηd, ηt, and ηSRH is formulated. Various values of ηSRH for different types of defect levels are presented. General ramification of the proposed concepts and efficacy of trapping is explored for polycrystalline thin film solar cells.
Photoexcitation of gigahertz longitudinal and shear acoustic waves in BiFeO3 multiferroic single crystal
Authors: Ruello P. , Pezeril T. , Avanesyan S. , Vaudel G. , Gusev V. , Infante I. C. , Dkhil B.
Published: May 2012

Using femtosecond laser pulses, coherent GHz acoustic phonons are efficiently photogenerated and photodetected in BiFeO3 (BFO) multiferroic single crystal. Due to the crystal lattice symmetry, longitudinal as well as two transverse acoustic modes are generated and detected, and the corresponding sound velocities are determined. This provides the opportunity to experimentally evaluate the elastic coefficients of the multiferroic compound BiFeO3 that have been estimated so far only through ab initio calculations. The knowledge of the elastic properties of BFO is highly desired for BFO integration in nanoelectronic devices. Moreover, our findings highlight also that BFO may be a good candidate for light-controlled coherent acoustic phonons sources.
Gyrosymmetry: Global considerations
Authors: Burby J. W. , Qin H.
Published: May 2012

In the guiding center theory, smooth unit vectors perpendicular to the magnetic field are required to define the gyrophase. The question of global existence of these vectors is addressed using a general result from the theory of characteristic classes. It is found that there is, in certain cases, an obstruction to global existence. In these cases, the gyrophase cannot be defined globally. The implications of this fact on the basic structure of the guiding center theory are discussed. In particular, it is demonstrated that the guiding center asymptotic expansion of the equations of motion can still be performed in a globally consistent manner when a single global convention for measuring gyrophase is unavailable. The latter fact is demonstrated directly by deriving a new expression for the guiding-center Poincaré-Cartan form exhibiting no dependence on the choice of perpendicular unit vectors.
Addendum to “Phase selection and transition in Hf-rich hafnia-titania nanolaminates” (on SiO2) [J. Appl. Phys. 109, 123523 (2011)]: Hafnon formation
Authors: Cisneros-Morales Massiel Cristina , Aita Carolyn Rubin
Published: May 2012

Continued investigation of hafnia-titania nanolaminates on silica substrates after long term annealing shows that hafnon (HfSiO4) is formed, in addition to the previously reported phases. Here, a 293 nm-thick stack of 5 nm HfO2-4 nm TiO2 bilayers (0.51 mole fraction HfO2) is sputter deposited on fused SiO2 and annealed in air at 1173 K for up to 192 h and then at 1273 K for up to 96 h. X-ray diffraction shows that hafnon crystallizes after 24 h at 1273 K. Micro-Raman spectroscopy/microscopy shows that hafnon crystallization is heterogeneous. No film-substrate reaction is observed for single layer HfO2 on SiO2 annealed under similar conditions. We suggest the nanolaminate’s complex annealed microstructure provides fast diffusion paths that enable hafnon formation.
Local explicitly correlated second- and third-order Møller–Plesset perturbation theory with pair natural orbitals
Authors: Hättig Christof , Tew David P. , Helmich Benjamin
Published: May 2012

We present an algorithm for computing explicitly correlated second- and third-order Møller–Plesset energies near the basis set limit for large molecules with a cost that scales formally as \documentclass[12pt]{minimal}\begin{document}${\cal N}^4$\end{document}N4 with system size \documentclass[12pt]{minimal}\begin{document}${\cal N}$\end{document}N. This is achieved through a hybrid approach where locality is exploited first through orbital specific virtuals (OSVs) and subsequently through pair natural orbitals (PNOs) and integrals are approximated using density fitting. Our method combines the low orbital transformation costs of the OSVs with the compactness of the PNO representation of the doubles amplitude vector. The \documentclass[12pt]{minimal}\begin{document}${\cal N}^4$\end{document}N4 scaling does not rely upon the a prioridefinition of domains, enforced truncation of pair lists, or even screening and the energies converge smoothly to the canonical values with decreasing occupation number thresholds, used in the selection of the PNO basis. For MP2.5 intermolecular interaction energies, we find that 99% of benchmark basis set limit correlation energy contributions are recovered using an aug-cc-pVTZ basis and that on average only 50 PNOs are required to correlate the significant orbital pairs.
The effect of interface modulation on phononic band gaps for longitudinal modes in semiconductor superlattices
Authors: Nowak P. , Krawczyk M.
Published: May 2012

We present the results of our theoretical investigation of the effect of a periodic interface modulation on the longitudinal vibrational modes in one-dimensional phononic crystals. Based on the plane wave method and the finite difference time domain method, our calculations show that the bottom and top of the first phononic gap can be controlled independently by adjusting the modulation introduced. The effective acoustic impedance of the modulated layers is demonstrated to be of key importance for the opening of phononic energy gaps. Band gaps for longitudinal modes can be expected to occur in a large range of interface inhomogeneity. The shape of the modulation proves not to have any significant effect on the investigated properties.
Steady-state nucleation rate and flux of composite nucleus at saddle point
Authors: Iwamatsu Masao
Published: May 2012

The steady-state nucleation rate and flux of composite nucleus at the saddle point is studied by extending the theory of binary nucleation. The Fokker-Planck equation that describes the nucleation flux is derived using the Master equation for the growth of the composite nucleus, which consists of the core of the final stable phase surrounded by a wetting layer of the intermediate metastable phase nucleated from a metastable parent phase recently evaluated by Iwamatsu [J. Chem. Phys. 134, 164508 (2011)]. The Fokker-Planck equation is similar to that used in the theory of binary nucleation, but the non-diagonal elements exist in the reaction rate matrix. First, the general solution for the steady-state nucleation rate and the direction of nucleation flux is derived. Next, this information is then used to study the nucleation of composite nucleus at the saddle point. The dependence of steady-state nucleation rate as well as the direction of nucleation flux on the reaction rate in addition to the free-energy surface is studied using a model free-energy surface. The direction of nucleation current deviates from the steepest-descent direction of the free-energy surface. The results show the importance of two reaction rate constants: one from the metastable environment to the intermediate metastable phase and the other from the metastable intermediate phase to the stable new phase. On the other hand, the gradient of the potential Φ or the Kramers crossover function (the commitment or splitting probability) is relatively insensitive to reaction rates or free-energy surface.
Correlation between fragility and eutectic instability and glass-forming ability in binary metallic glasses under growth controlled conditions
Authors: Wang N. , Ji L. , Yao W. J. , Zheng Y. P.
Published: May 2012

We find that the fragility can be correlated to the eutectic instability and the glass forming ability in binary metallic glass formers under growth controlled conditions via a dimensionless parameter β defined as DfT0/2(Te − T0), where Df is fragility parameter, T0 is Vogel-Fulcher-Tammann temperature, and Te is eutectic temperature. It is shown that the large β value, which results from high Df and from that T0 is close to the eutectic temperature, can lead to small interface growth velocity and undercooling of eutectic structure, and good glass forming ability. This indicates that high β leads to small characteristic diffusion length resulting from sluggish material transport that governs the glass forming ability. The results might provide an in-depth insight into the glass formation mechanism and be helpful for searching new glasses in growth controlled process.
Nano γ′/γ″ composite precipitates in Alloy 718
Authors: Phillips P. J. , McAllister D. , Gao Y. , Lv D. , Williams R. E. A. , Peterson B. , Wang Y. , Mills M. J.
Published: May 2012

Nanoscale composite precipitates of Alloy 718 have been investigated with both high-resolution scanning transmission electron microscopy and phase field modeling. Chemical analysis via energy-dispersive x-ray spectroscopy allowed for the differentiation of γ′ and γ″ particles, which is not otherwise possible through traditional Z-contrast methods. Phase field modeling was applied to determine the stress distribution and elastic interaction around and between the particles, respectively, and it was determined that a composite particle (of both γ′ and γ″) has an elastic energy that is significantly lower than, for example, single γ′ and γ″ precipitates which are non-interacting.
Emergence of a thread-like pattern with charged phospholipids on an oil/water interface
Authors: Ito Hiroaki , Yanagisawa Miho , Ichikawa Masatoshi , Yoshikawa Kenichi
Published: May 2012

The spontaneous formation of a thread-like pattern with negatively charged lipids on an oil/water interface is reported. An analysis of the time-dependent change at the interface observed by fluorescence microscopy revealed that the thread-like pattern is generated through a two-step mechanism. First, inverted lipid micelles in the bulk-oil phase gradually diffuse onto the oil/water interface. Next, the micelles are adsorbed on the interface and self-assemble to form the thread-like pattern. The essential characteristics of this pattern formation are theoretically reproduced by a simple Monte Carlo simulation that takes into account the kinetics in the coalescence of charged micelles on a 2D interface.
Intrinsic origin of negative fixed charge in wet oxidation for silicon carbide
Authors: Ebihara Yasuhiro , Chokawa Kenta , Kato Shigenori , Kamiya Katsumasa , Shiraishi Kenji
Published: May 2012

We demonstrate on the basis of first-principles calculations that the formation of carbonate-like moiety in SiO2 could be the intrinsic origin of negative fixed charge in SiC thermal oxidation. We find that two possible origins for the negative fixed charges are O-lone-pair state and a negatively charged CO3 ion in SiO2. Such CO3 ion is able to be formed as a result of the existence of residual C atoms in SiO2, which are expected to be emitted from the interface between SiC and SiO2, and the incorporation of H atoms during wet oxidation.
Expert Performance by Athletes in the Verbal Estimation of Spatial Extents Does Not Alter Their Perceptual Metric of Space
Authors: Durgin Frank H , Leonard-Solis Keenan , Masters Owen , Schmelz Brittany , Li Zhi
Published: May 2012

Athletes often give more accurate estimates of egocentric distance along the ground than do non-athletes. To explore whether cognitive calibration was accompanied by perceptual change, athletes and non-athletes made verbal height and distance estimates and also did a perceptual matching task between perceived egocentric distances and frontal vertical extents. Both groups were well calibrated for height estimation for poles viewed frontally, but athletes were much better calibrated at estimating longer egocentric distances (which are systematically underestimated by non-athletes). Athletes were more likely to have learned specific units of ground distance from relevant sports contexts. Both groups reported using human height as a metric for vertical extent. For non-athletes, verbal underestimation of ground distance corresponded to predictions based on perceptual matches between egocentric distances and vertical extents in conjunction with human-height-based verbal estimates of vertical extents. For athletes, the verbal scaling of egocentric distances of 10 m or more was more accurate and was not predicted by their egocentric distance matches to vertical extents.
Addressing the workplace needs of Western Australian midwives: a Delphi study
Authors: Hauck Yvonne L. , Bayes Sara J. , Robertson Jeanette M.
Published: May 2012

Objective. To determine the workplace needs of Western Australian midwives working in public metropolitan secondary hospitals. Method. Using a three-round Delphi approach, Round 1 incorporated focus groups and a questionnaire. Fifteen focus groups were conducted with midwives also having the option of contributing through an open-ended questionnaire. During Round 2, 38 items reflecting seven themes were prioritised with a final ranking performed in Round 3. In total, 114 midwives participated in Round 1, 72 in Round 2 and 89 in Round 3. Results. During Round 1, workplace needs identified as being met included: working across all areas of midwifery; ability to work in areas of interest; opportunity to work with low to moderate risk women; supportive colleagues; accessible parking; hospital close to home and friendly work atmosphere. Round 2 items revealed the five top unmet needs as: adequate midwifery staff coverage; access to maintained equipment; competitive pay scales; patient safety issues and opportunities to implement midwifery models. The top ranked needs from Round 3 included: recognising the unpredictable nature of midwifery services; provision of competent medical coverage, and adequate midwifery staff coverage. Conclusions. Demand for maternity services is unpredictable; however, in order to maintain a sustainable maternity workforce, WA midwives’ prioritised needs would suggest health management focus upon expanding the availability of midwifery models of care, fostering flexible working conditions and ensuring collaboration between maternity health professionals occurs within clinically safe staffing levels. What is known about the topic? Dissatisfaction with working conditions, staff shortages, and feeling undervalued or unsupported contribute to healthcare workforce attrition. However, positive practice environments and health service management and leadership can influence employee satisfaction and retention. What does this paper add? These insights into Western Australian midwives’ met and unmet needs within the context of public metropolitan secondary units provide a more practical basis for the revision of work conditions than has been reported previously. What are the implications for practitioners? Our findings reinforce the urgent need to address the midwifery workforce priorities highlighted in the Australian National Maternity Services Plan. Specifically, this study strongly underscores the requirement to expand the availability of midwifery models of care, foster flexible working conditions and ensure collaboration between maternity health professionals occurs within clinically safe staffing levels.
Cenozoic climate change shaped the evolutionary ecophysiology of the Cupressaceae conifers
Authors: Pittermann Jarmila , Stuart Stephanie A. , Dawson Todd E. , Moreau Astrid
Published: May 2012

The Cupressaceae clade has the broadest diversity in habitat and morphology of any conifer family. This clade is characterized by highly divergent physiological strategies, with deciduous swamp-adapted genera-like
Taxodium
at one extreme, and evergreen desert genera-like
Cupressus
at the other. The size disparity within the Cupressaceae is equally impressive, with members ranging from 5-m-tall juniper shrubs to 100-m-tall redwood trees. Phylogenetic studies demonstrate that despite this variation, these taxa all share a single common ancestor; by extension, they also share a common ancestral habitat. Here, we use a common-garden approach to compare xylem and leaf-level physiology in this family. We then apply comparative phylogenetic methods to infer how Cenozoic climatic change shaped the morphological and physiological differences between modern-day members of the Cupressaceae. Our data show that drought-resistant crown clades (the Cupressoid and Callitroid clades) most likely evolved from drought-intolerant Mesozoic ancestors, and that this pattern is consistent with proposed shifts in post-Eocene paleoclimates. We also provide evidence that within the Cupressaceae, the evolution of drought-resistant xylem is coupled to increased carbon investment in xylem tissue, reduced xylem transport efficiency, and at the leaf level, reduced photosynthetic capacity. Phylogenetically based analyses suggest that the ancestors of the Cupressaceae were dependent upon moist habitats, and that drought-resistant physiology developed along with increasing habitat aridity from the Oligocene onward. We conclude that the modern biogeography of the Cupressaceae conifers was shaped in large part by their capacity to adapt to drought.
Data-driven unbiased curation of the
TP53
tumor suppressor gene mutation database and validation by ultradeep sequencing of human tumors
Authors: Edlund Karolina , Larsson Ola , Ameur Adam , Bunikis Ignas , Gyllensten Ulf , Leroy Bernard , Sundström Magnus , Micke Patrick , Botling Johan , Soussi Thierry
Published: May 2012

Cancer mutation databases are expected to play central roles in personalized medicine by providing targets for drug development and biomarkers to tailor treatments to each patient. The accuracy of reported mutations is a critical issue that is commonly overlooked, which leads to mutation databases that include a sizable number of spurious mutations, either sequencing errors or passenger mutations. Here we report an analysis of the latest version of the
TP53
mutation database, including 34,453 mutations. By using several data-driven methods on multiple independent quality criteria, we obtained a quality score for each report contributing to the database. This score can now be used to filter for high-confidence mutations and reports within the database. Sequencing the entire
TP53
gene from various types of cancer using next-generation sequencing with ultradeep coverage validated our approach for curation. In summary, 9.7% of all collected studies, mostly comprising numerous tumors with multiple infrequent
TP53
mutations, should be excluded when analyzing
TP53
mutations. Thus, by combining statistical and experimental analyses, we provide a curated mutation database for
TP53
mutations and a framework for mutation database analysis.
The UEA sRNA workbench: a suite of tools for analysing and visualizing next generation sequencing microRNA and small RNA datasets
Authors: Stocks Matthew B. , Moxon Simon , Mapleson Daniel , Woolfenden Hugh C. , Mohorianu Irina , Folkes Leighton , Schwach Frank , Dalmay Tamas , Moulton Vincent
Published: May 2012

Summary: RNA silencing is a complex, highly conserved mechanism mediated by small RNAs (sRNAs), such as microRNAs (miRNAs), that is known to be involved in a diverse set of biological functions including development, pathogen control, genome maintenance and response to environmental change. Advances in next generation sequencing technologies are producing increasingly large numbers of sRNA reads per sample at a fraction of the cost of previous methods. However, many bioinformatics tools do not scale accordingly, are cumbersome, or require extensive support from bioinformatics experts. Therefore, researchers need user-friendly, robust tools, capable of not only processing large sRNA datasets in a reasonable time frame but also presenting the results in an intuitive fashion and visualizing sRNA genomic features. Herein, we present the UEA sRNA workbench, a suite of tools that is a successor to the web-based UEA sRNA Toolkit, but in downloadable format and with several enhanced and additional features.

Availability: The program and help pages are available at http://srna-workbench.cmp.uea.ac.uk.

Contact:  vincent.moulton@cmp.uea.ac.uk
Beam trawlermen take feet off gas in response to oil price hikes
Authors: Beare Doug , Machiels Marcel
Published: May 2012

Beare, D., and Machiels, M. 2012. Beam trawlermen take feet off gas in response to oil price hikes. – ICES Journal of Marine Science, 69: 1064–1068. Average towing speed by Dutch beam trawlermen has fallen substantially between 2002 and 2009. Changes in towing speed are related to changes in oil price. The price of their valuable main target species (sole, Solea vulgaris) did not influence towing speed.
Utilization of Critical Care Services among Patients Undergoing Total Hip and Knee Arthroplasty
Authors: Memtsoudis Stavros G. , Sun Xuming , Chiu Ya-Lin , Nurok Michael , Stundner Ottokar , Pastores Stephen M. , Mazumdar Madhu
Published: May 2012

Background

A paucity of data exist on the use of critical care services (CCS) among hip and knee arthroplasty patients. The authors sought to identify the incidence and risk factors for the use of CCS among these patients and compare the characteristics and outcomes of patients who require CCS to those who do not.

Methods

The authors analyzed hospital discharge data of patients who underwent primary hip or knee arthroplasty in approximately 400 United States hospitals between 2006 and 2010. Patient and healthcare system-related demographics for admitted patients requiring CCS were compared with those who did not. Differences in outcomes, including mortality, complications, disposition status, and hospital charges, were analyzed. Regression analysis was performed to identify risk factors for requiring CCS.

Results

A total of 528,495 patients underwent primary total hip (n = 172,467, 33%) and knee arthroplasty (n = 356,028, 67%). Of these, 3% required CCS. On average, CCS patients were older and had a higher comorbidity burden than did patients not requiring CCS. CCS patients experienced more complications, had longer hospital stays and higher costs, and were less likely to be discharged home than were non-CCS patients. Risk factors with increased odds for requiring CCS included advanced age, use of general versus neuraxial anesthesia, and the presence of postoperative cardiopulmonary complications.

Conclusions

Approximately 1 of 30 patients undergoing total joint arthroplasty requires CCS. Given the large number of these procedures performed annually, anesthesiologists, orthopedic surgeons, critical care physicians, and administrators should be aware of the attendant risks this population represents and allocate resources accordingly.
Regulation of Peripheral Clock to Oscillation of Substance P Contributes to Circadian Inflammatory Pain
Authors: Zhang Jing , Li Huili , Teng Huajing , Zhang Ting , Luo Yonglun , Zhao Mei , Li Yun-Qing , Sun Zhong Sheng
Published: May 2012

Background

The daily fluctuations of many physiologic and behavioral parameters are differentially influenced by either central or peripheral clocks in mammals. Since substance P (SP) oscillates in some brain tissues and plays an indispensable role in modulating inflammatory pain at the spinal level, we speculated that SP mediates circadian nociception transmission at the spinal level.

Methods

In the present study behavioral observation, real-time polymerase chain reaction, luciferase assay, chromatin immunoprecipitation, and immunohistochemistry stain methods were used to investigate the role of SP in the spinal circadian nociception transmission and its regulation mechanism.

Results

Our results showed that under transcriptional regulation of BMAL1:CLOCK heterodimers, SP's coding gene Tac1 expression oscillates in dorsal root ganglion (n = 36), but not in the spinal dorsal horn. Further, the expression of SP cycled in the spinal dorsal horn, and this rhythmicity was potentially determined by circadian expression of Tac1 in dorsal root ganglion. Furthermore, the variation of SP expression induced by formalin was fluctuated in a similar rhythm to behavioral nociceptive response induced by formalin (n = 48); and the nociceptive behavioral circadian rhythm could be abolished through blockade of the SP-Neurokinin 1 receptor pathway (n = 70). Lastly, the variations of spinal SP expression and behavioral nociceptive response were in step, and both were changed by the deletion mutation of clock gene.

Conclusions

We conclude that spinal SP probably plays a pivotal role in modulating circadian inflammatory pain and suggest that peripheral circadian-regulated signaling is potentially an essential pathway for circadian nociceptive transmission.