bluuebunny/crossref_metadata_2025 huggingface dataset:
Methods for registration of magnetic resonance images of ex vivo prostate specimens with histology
Authors: Kimm Simon Y. , Tarin Tatum V. , Lee Jin Hyung , Hu Bob , Jensen Kristin , Nishimura Dwight , Brooks James D.
Published: February 2012

Purpose:

To evaluate two methods of scanning and tissue processing to achieve accurate magnetic resonance (MR)‐histologic correlation in human prostate specimens.

Materials and Methods:

Two prostates had acrylic paint markers injected to define the plane of imaging and serve as internal fiducials. Each was placed on a polycarbonate plane‐finder device (PFD), which was adjusted to align the imaging and cutting planes. Three prostates were aligned by use of a plane finder key (PFK), a polycarbonate plate that locks the specimen in a cylindrical carrier. Markers were injected for registration analysis. Prostates were imaged, then sectioned. Imaging software was used to create registration maps of the MR and histology images. Measurements between control points were made and compared.

Results:

Accurate correlation was achieved between MR and histologic images. The mean displacement (MD) between the corresponding registration points using the PFD technique ranged from 1.11–1.38 mm for each section. The MD for all sections was 1.24 mm. The MD using the PFK technique ranged from 0.79–1.01 mm for each section, and the MD across all sections for the PFK was 0.92 mm.

Conclusion:

We describe two methods that can achieve accurate, reproducible correlation between MR imaging and histologic sections in human prostatectomy specimens. J. Magn. Reson. Imaging 2012;36:206–212. © 2012 Wiley Periodicals, Inc.
MR enterography: Relationship between intestinal fold pattern and the clinical presentation of adult celiac disease
Authors: Tomei Ernesto , Diacinti Daniele , Stagnitti Andrea , Marini Mario , Laghi Andrea , Passariello Roberto , Semelka Richard C.
Published: February 2012

Purpose:

To correlate the clinical presentation of adult celiac disease with various intestinal fold patterns using MR‐enterography.

Materials and Methods:

Fifty‐four consecutive adult celiac patients (34 female, 20 male, 18 to 62 years) were studied by MR‐enterography. Two radiologists blinded to the patients' clinical history evaluated in consensus MR studies, classifying the intestinal fold pattern into four categories: (a) no fold abnormalities, (b) isolated loss of folds in the duodenum, (c) jejunization of ileum, and (d) jejuno‐ileal fold pattern reversal. Patients presented with the varying clinical forms of Celiac disease, classified as: (i) typical disease, (ii) atypical disease, and (iii) silent form.

Results:

Twenty‐three patients showed no intestinal fold abnormalities; 11 patients had isolated loss of duodenal folds; 9 patients showed jejunization of ileum and 11 had jejuno‐ileal fold pattern reversal. 18/23 (78%) patients with MRI normal fold pattern had the silent clinical form of Celiac disease (Sensitivity 78%; specificity 100%; PPV = 1, NPV = 0.78); 9/11 (82%) patients with the isolated loss of duodenal folds had the atypical clinical form (sensitivity 82%; and specificity 100%; PPV = 1; NPV = 0.82). All 20 patients with the jejunization of ileum and jejuno‐ileal fold pattern reversal had typical celiac disease (sensitivity and specificity of 100%; PPV and NPV = 1).

Conclusion:

MR‐enterography findings in patients with celiac disease, demonstrates good correlation between MR findings and clinical severity. J. Magn. Reson. Imaging 2012;36:183–187. © 2012 Wiley Periodicals, Inc.
Resettlement and woodland management problems and options: a case study from North‐western Ethiopia
Authors: Lemenih M. , Kassa H. , Kassie G. T. , Abebaw D. , Teka W.
Published: February 2012

Deforestation in African dry forests is widespread and its drivers are complex and vary in space and time. In this paper, we assessed impacts of immigration on dry forests and options for improved management in a resettlement district in north‐western Ethiopia. Key informants interviews, focus group discussions and household questionnaire survey were used to collect data. The results indicated that forests of the district are degrading in spatial coverage and quality. The most important drivers were land use change, excessive wood harvest, grazing pressure and forest fire following immigration. The continuous influx of people with different origins, cultures, religions and lengths of residence in the district underscores absence of social bonds for collective action to regulate access. This, coupled with weak formal regulatory system, market forces and policy incentives for farming, resulted in a near open access situation. Our findings confirm the negative relationships between migration and environment not necessarily because of the mere population number added through immigration but because of lack of regulatory frameworks (formal or informal) and poor social capital. Enforcing existing policy of farm size and putting institutional framework on the ground to regulate rate of immigration, extraction of forest products and to encourage tree planting to meet wood demand are suggested measures. We conclude that Government programmes that opt for resettlement as a measure for poverty alleviation must also have mitigating measures to reducing negative impacts on the natural resource base. Thus, the trade‐off between environment and development must be carefully managed. Copyright © 2012 John Wiley & Sons, Ltd.
Splitting of Pi and other 31P NMR anomalies of skeletal muscle metabolites in canine muscular dystrophy
Authors: Wary Claire , Naulet Thibaud , Thibaud Jean‐Laurent , Monnet Aurélien , Blot Stéphane , Carlier Pierre G.
Published: February 2012

Many anomalies exist in the resting 31P muscle spectra of boys with Duchenne muscular dystrophy (DMD) but few have been reported in Golden Retriever muscular dystrophy (GRMD), the closest existing animal model for DMD. Because GRMD is recommended for preclinical evaluation of therapies and quantitative outcome measures are needed, we investigated anomalies of 31P NMRS in tibial cranial and biceps femoris muscles from 14 GRMD compared to 9 control (CONT) dogs.

Alterations observed in DMD children – low phosphocreatine and high phospho‐monoesters and ‐diesters – were all found in GRMD but increased pH was not. More surprisingly, inorganic phosphate (Pi) appeared to present a prominent splitting with an enhanced Pib resonance at 0.3 ppm downfield of Pia. Assuming that both resonances are Pi, the pH for Pia in GRMD corresponded to a physiological intracellular pHa (6.97 ± 0.05), while pHb approached the extracellular range (7.27 ± 0.10) and correlated with pHa in GRMD (R2 = 0.65). Both Pia and Pib were elevated compared to CONT and Pia increased with age for GRMD (R2 = 0.48, p < 0.001).

Magnetisation transfer experiments between γATP and Pi were conducted to better characterise Pi pools. Equal T1 relaxation times for Pib and Pia did not support a mitochondrial origin of Pib. We suggest that Pib could originate from degenerating hypercontracted cells that have a leaky membrane and inadequate cell homeostasis and pH regulation. Pib showed minimal chemical exchange in all dogs, while the exchange rate of Pia was reduced in GRMD and might extraneously reflect low glycolytic activity in DMD.

Taken together, the ensemble of 31P NMRS alterations identifies muscle dysfunction and could provide useful biomarkers of therapeutic efficacy. Furthermore, among these, two might relate more specifically to dystrophic processes and merit further investigation: one is the existence of the enhanced alkaline Pib pool; the other, mechanisms by which membrane disruption might increase phosphodiesters in dystrophy. Copyright © 2012 John Wiley & Sons, Ltd.
Theoretical study of spectroscopic and molecular properties of several low‐lying electronic states of CO molecule
Authors: Shi De‐Heng , Li Wen‐Tao , Sun Jin‐Feng , Zhu Zun‐Lue
Published: February 2012

The potential energy curves (PECs) of eight low‐lying electronic states (X1Σ+, a3Π, a′3Σ+, d3Δ, e3Σ−, A1Π, I1Σ−, and D1Δ) of the carbon monoxide molecule have been studied by an ab initio quantum chemical method. The calculations have been performed using the complete active space self‐consistent field method, which is followed by the valence internally contracted multireference configuration interaction (MRCI) approach in combination with the correlation‐consistent aug‐cc‐pV5Z basis set. The effects on the PECs by the core‐valence correlation and relativistic corrections are included. The way to consider the relativistic corrections is to use the third‐order Douglas–Kroll Hamiltonian approximation at the level of a cc‐pV5Z basis set. Core‐valence correlation corrections are performed using the cc‐pCVQZ basis set. To obtain more reliable results, the PECs determined by the MRCI calculations are corrected for size‐extensivity errors by means of the Davidson modification (MRCI+Q). The spectroscopic parameters (De, Te, Re, ωe, ωexe, ωeye, Be, αe, and γe) of these electronic states are calculated using these PECs. The spectroscopic parameters are compared with those reported in the literature. Using the Breit–Pauli operator, the spin–orbit coupling effect on the spectroscopic parameters is discussed for the a3Π electronic state. With the PECs obtained by the MRCI+Q/aug‐cc‐pV5Z+CV+DK calculations, the complete vibrational states of each electronic state have been determined. The vibrational manifolds have been calculated for each vibrational state of each electronic state. The vibrational level G(ν), inertial rotation constant Bν, and centrifugal distortion constant Dν of the first 20 vibrational states when the rotational quantum number J equals zero are reported and compared with the experimental data. Comparison with the measurements demonstrates that the present spectroscopic parameters and molecular constants determined by the MRCI+Q/aug‐cc‐pV5Z+CV+DK calculations are both reliable and accurate. © 2012 Wiley Periodicals, Inc.
Innate immune interferon responses to Human immunodeficiency virus‐1 infection
Authors: Hughes Rose , Towers Greg , Noursadeghi Mahdad
Published: February 2012

Type I interferon (IFN) responses represent the canonical host innate immune response to viruses, which serves to upregulate expression of antiviral restriction factors and augment adaptive immune defences. There is clear evidence for type I IFN activity in both acute and chronic HIV‐1 infection in vivo, and plasmacytoid dendritic cells have been identified as one important source for these responses, through innate immune detection of viral RNA by Toll‐like receptor 7. In addition, new insights into the molecular mechanisms that trigger induction of type I IFNs suggest innate immune receptors for viral DNA may also mediate these responses. It is widely recognised that HIV‐1 restriction factors share the characteristic of IFN‐inducible expression, and that the virus has evolved to counteract these antiviral mechanisms. However, in some target cells, such as macrophages, IFN can still effectively restrict virus. In this context, HIV‐1 shows the ability to evade innate immune recognition and thereby avoid induction of type I IFN in order to successfully establish productive infection. The relative importance of evasion of innate immune detection and evasion of IFN‐inducible restriction in the natural history of HIV‐1 infection is not known, and the data suggest that type I IFN responses may play a role in both viral control and in the immunopathogenesis of progressive disease. Further study of the relationship between HIV‐1 infection and type I IFN responses is required to unravel these issues and inform the development of novel therapeutics or vaccine strategies. Copyright © 2012 John Wiley & Sons, Ltd.
Selectively chosen ciphertext security in threshold public‐key encryption
Authors: Kim Kitak , Park Jong Hwan , Lee Dong Hoon
Published: February 2012

Threshold public‐key encryption can control decryption abilities of an authorized user group in such a way that each user of the group can produce only a decryption share and at least t of them should collect decryption shares to recover a message. We present a new threshold public‐key encryption that is secure against selectively chosen ciphertext attacks. Semantic security against chosen ciphertext adversaries is the de facto level of security for public‐key encryption deployed in practice because many encryption systems are broken in a model of chosen ciphertext security. The security of the proposed system is formally proved without random oracles under a new assumption. We also provide proof of the intractability of our assumption in the generic group model. Copyright © 2012 John Wiley & Sons, Ltd.
Synthesis of Monodisperse, Covalently Cross‐Linked, Degradable “Smart” Microgels Using Microfluidics
Authors: Kesselman Leah R. B. , Shinwary Siawash , Selvaganapathy P. Ravi , Hoare Todd
Published: February 2012

The development of a robust method for the synthesis of highly monodisperse microgels cross‐linked with degradable covalent bonds offers the potential for fabricating microgels with the highly controllable porosities, cell interactions, and degradation half‐lives required for biomedical applications. A microfluidic chip is designed that enables the on‐chip mixing and emulsification of two reactive polymer solutions (hydrazide and aldehyde‐functionalized carbohydrates) to form monodisperse, hydrazone cross‐linked microgels in the size range of ≈40–100 μm. The device can be run continuously for at least 30 h without a significant drift in particle size. The resulting microgels have a homogeneous bulk composition and can swell and deswell as the solvent conditions change in predictable ways based on the chemistry of the reactive polymers used, thereby enabling improved control over both the chemistry and morphology of the resulting microgels relative to other reported approaches. The in situ gelation chemistry used facilitates rapid microgel formation within the droplets without requiring the use of UV light or heating to initiate polymerization, thus making this approach of particular potential utility in cell encapsulation or drug delivery (as demonstrated).
An Improved Method for Synthesis of N‐stearoyl and N‐palmitoylethanolamine
Authors: Wang Xiaosan , Wang Tong , Wang Xingguo
Published: February 2012

Certain N‐acylethanolamines interact with cannabinoid receptors and have anorexic and neuroprotective effects. Traditional methods for the synthesis of N‐acylethanolamines use fatty acid chlorides, fatty acid methyl esters, free fatty acids and triacylglycerols as acyl donors to react with ethanolamine. In the present study, we investigated the feasibility of using fatty acid vinyl esters as the acyl donor to synthesize N‐stearoyl and N‐palmitoylethanolamine. Theoretically, the use of fatty acid vinyl esters should lead to an irreversible reaction because the volatile acetaldehyde by‐product is easily removed. Four reaction conditions, i.e. catalyst concentration, substrate ratio, temperature, and time were evaluated. The reaction performed at mild temperatures and with an excess amount of ethanolamine which acted as both reactant and solvent resulted in the formation of high purity N‐stearoyl and N‐palmitoylethanolamine. When 20 mmol ethanolamine was reacted with 1 mmol vinyl stearate at 80 °C for 1 h with 1% sodium methoxide as catalyst, N‐stearoylethanolamine with 96% purity was obtained after the removal of excess ethanolamine without further purification, while N‐palmitoylethanolamine with 98% purity was obtained by reacting with the same substrate ratio at 60 °C for 1.5 h with 3% catalyst. Complete conversion of vinyl stearate and palmitate was achieved.
A neglected phonetic law: The assimilation of pretonic yod to a following coronal in North-West Semitic
Authors: Garnier Romain , Jacques Guillaume
Published: February 2012

This paper shows the existence of a pretonic assimilation of *y to a following coronal consonant (including *y from proto-Semitic *y and *w) in North-West Semitic languages. This rule, which has been obscured by analogy in each of the North-West Semitic languages, explains three independent sets of facts: the formation of irregular maqtal-s in Hebrew, Phoenician and Aramaic; the irregular conjugations of several verbs in Hebrew; and the plural formation of the irregular noun “house” in Hebrew and Aramaic. This proposal also solves the long-standing problem of the etymology of the verb “to give” in North-West Semitic languages (NTN in Hebrew vs. YTN in Phoenician).
Semantically interoperable three-dimensional scientific objects
Authors: Pitikakis Marios , Vavalis Manolis , Houstis Catherine
Published: February 2012

In recent years, digital content of three-dimensional (3D) scientific objects has become widespread and is made available in a plethora of on-line scientific repositories. A systematic and formal approach becomes necessary to represent the knowledge/information related to these objects, in order to facilitate their search, retrieval and reuse. In this paper, we employ semantic interoperability to manage 3D scientific object content in a large-scale framework of scientific applications that consists of 3D shape models, associated tools and resources. We use an advanced ontological organization for their metadata, powerful reasoning engines for their search and retrieval and we elucidate several crucial issues in the design and implementation of 3D knowledge-based management systems.
Modeling knowledge dynamics in multi-agent systems based on informants
Authors: Tamargo Luciano H. , García Alejandro J. , Falappa Marcelo A. , Simari Guillermo R.
Published: February 2012

In this paper, we model knowledge dynamics in agents’ belief bases in a collaborative multi-agent system (MAS). Four change operators are introduced: expansion, contraction, prioritized revision, and non-prioritized revision. For all of them, both constructive definitions and an axiomatic characterization by representation theorems are given. We formally justify minimal change, consistency maintenance, and non-prioritization principles. These operators are based on an epistemic model for multi-source belief revision in which a rational way to weigh the beliefs using a credibility order among agents is developed. The defined operators can be seen as skills added to the agents improving the collective reasoning of a MAS.
Electromagnetic design analysis and performance improvement of axial field permanent magnet generator for small wind turbine
Authors: Jung Tae-Uk
Published: February 2012

Axial field permanent magnet (AFPM) generators are widely applied for the small wind turbine. The output power of conventional AFPM generator, AFER-NS (Axial Field External Rotor–Non Slotted) generator, is limited by the large reluctance by the long air-gap flux paths. In this paper, the novel structure of AFPM generator, AFIR-S (Axial Field Inner Rotor–Slotted) generator, is suggested to improve the output characteristics. The electromagnetic design analysis and the design improvement of the suggested AFIR-S generator are studied. Firstly, the electromagnetic design analysis was done to increase the power density. Secondly, the design optimizations of the rotor pole-arc ratio and skew angle to increase the output power and to reduce the cogging torque. Finally, the output performances of AFER-NS and AFIR-S generator are compared with each other.
Design and fabrication of Dy-free sintered permanent magnets with high coercivity
Authors: Chen Bicheng , Liu Xingmin , Chen Renjie , Guo Shuai , Yan Changjiang , Lee Don , Yan Aru
Published: February 2012

The purpose of this study was to save heavy rare earth Dy in NdFeB production. By ways of optimizing preparation process and replacing Nd with Pr, Dy-free magnet with high coercivity was successfully prepared, the nominal composition is Pr14B6Co2.2Cu0.2Al1Fe76.7 (at %). The effect of Pr on magnetic performance and microstructure of the magnet were investigated systemically, alloy Nd13.65B6Co2.2Cu0.2Al1Fe76.9 (at %) was prepared by the same preparation process as comparison. The results indicated that magnet Pr14B6Co2.2Cu0.2Al1Fe76.7 has much higher coercivity than that of magnet Nd13.65B6Co2.2Cu0.2Al1Fe76.9. Microstructure investigation showed that the presence of small grains, thin and smooth RE-rich film, associated with higher coercivity.
Numerical analysis of surface produced H− ions by using two-dimensional particle-in-cell method
Authors: Miyamoto K. , Okuda S. , Hatayama A. , Hanada M.
Published: February 2012

The modeling and analysis of a negative ion source is proceeding by using a 2D particle-in-cell simulation. The effect of the H− ion production on the plasma grid (PG) surface is investigated. It is shown that with the increase of H− ions per time step, the H− ion current density is enhanced, while the electron current density decreases with increasing the H− production rate on the PG surface. These results agree well with the experimental results observed in typical negative ion sources. Moreover, it is found that plasma quasi-neutrality is held mainly by both H+ and H− ions in the bulk plasma around the PG.
Magnetic domain observation of Nd–Cu-diffused Nd–Fe–B magnets with submicron grains by Kerr effect microscopy
Authors: Takezawa M. , Nagashima Y. , Kimura Y. , Morimoto Y. , Yamasaki J. , Nozawa N. , Nishiuchi T. , Hirosawa S.
Published: February 2012

The domain structure and magnetization process of Nd–Cu-diffused magnets prepared from hydrogenation–disproportionation–desorption–recombination (HDDR)-processed powders and Nd–Cu powders were examined with a high-resolution Kerr microscope using an ultraviolet light source. We found that the coercivity of the HDDR magnet depends on the volume of magnetically coupled grains that simultaneously reverse their magnetization. In a magnet that has no Nd–Cu, and in which the Nd-rich phase along the grain boundaries is absent, magnetization reversal simultaneously occurs in several grains. In contrast, in a Nd–Cu-diffused magnet that contains adequate Nd-rich phases along the grain boundaries, magnetization reversal occurs independently in each grain. It follows that the change in microstructure caused by the presence of Nd–Cu leads to a decoupled magnetization reversal, and domain wall pinning is an important coercivity mechanism of an HDDR magnet compacted by hot-pressing.
Voltage holding study of 1 MeV accelerator for ITER neutral beam injector
Authors: Taniguchi M. , Kashiwagi M. , Umeda N. , Dairaku M. , Takemoto J. , Tobari H. , Tsuchida K. , Yamanaka H. , Watanabe K. , Kojima A. , Hanada M. , Sakamoto K. , Inoue T.
Published: February 2012

Voltage holding test on MeV accelerator indicated that sustainable voltage was a half of that of ideal quasi-Rogowski electrode. It was suggested that the emission of the clumps is enhanced by a local electric field concentration, which leads to discharge initiation at lower voltage. To reduce the electric field concentration in the MeV accelerator, gaps between the grid supports were expanded and curvature radii at the support corners were increased. After the modifications, the accelerator succeeded in sustaining −1 MV in vacuum without beam acceleration. However, the beam energy was still limited at a level of 900 keV with a beam current density of 150 A/m2 (346 mA) where the 3 × 5 apertures were used. Measurement of the beam profile revealed that deflection of the H− ions was large and a part of the H− ions was intercepted at the acceleration grid. This causes high heat load on the grids and the breakdowns during beam acceleration. To suppress the direct interception, new grid system was designed with proper aperture displacement based on a 3D beam trajectory analysis. As the result, the beam deflection was compensated and the voltage holding during the beam acceleration was improved. Beam parameter of the MeV accelerator was increased to 980 keV, 185 A/m2 (427 mA), which is close to the requirement of ITER accelerator (1 MeV, 200 A/m2).
Thermal and electrostatic simulations of the diagnostic calorimeter for the Source for Production of Ion of Deuterium Extracted from RF plasma beam
Authors: Serianni G. , Dalla Palma M. , De Muri M. , Fasolo D. , Pasqualotto R. , Pomaro N. , Rizzolo A. , Tollin M.
Published: February 2012

To study and optimise negative ion production for the ITER neutral beam injectors, a test facility is under construction in Padova with the aim of testing beam characteristics and to verify the source proper operation. The instrumented calorimeter STRIKE (short-time retractable instrumented kalorimeter experiment) is being developed to characterise the SPIDER (Source for Production of Ion of Deuterium Extracted from RF plasma) beam during short operations. The paper presents an investigation of the response of STRIKE measurement systems. It results that biasing is necessary to cope with the influence of secondary electrons on current measurements; moreover, despite the discretisation of the recorded thermal patterns introduced by the pixels of thermal cameras, a sufficient spatial resolution is expected
Field-induced changes in polarization and magnetization in Tb0.3Dy0.7Fe2/PZT laminate composite
Authors: Zhang Hui
Published: February 2012

We have presented a theoretical model to describe the magnetoelectric coupling in Tb0.3Dy0.7Fe2/PZT laminate composite material. In this model, the stresses introduced by the magnetic field or electric field in the composite material are assumed to be the axial force. The magnetization of magnetostrictive phase can indirectly couple with the electrical polarization of piezoelectric phase through the stresses. The numerical results have shown that both the magnetic field and electric field can cause significant changes in the magnetization and electric polarization in the composite material.
Mapping quantum-classical Liouville equation: Projectors and trajectories
Authors: Kelly Aaron , van Zon Ramses , Schofield Jeremy , Kapral Raymond
Published: February 2012

The evolution of a mixed quantum-classical system is expressed in the mapping formalism where discrete quantum states are mapped onto oscillator states, resulting in a phase space description of the quantum degrees of freedom. By defining projection operators onto the mapping states corresponding to the physical quantum states, it is shown that the mapping quantum-classical Liouville operator commutes with the projection operator so that the dynamics is confined to the physical space. It is also shown that a trajectory-based solution of this equation can be constructed that requires the simulation of an ensemble of entangled trajectories. An approximation to this evolution equation which retains only the Poisson bracket contribution to the evolution operator does admit a solution in an ensemble of independent trajectories but it is shown that this operator does not commute with the projection operators and the dynamics may take the system outside the physical space. The dynamical instabilities, utility, and domain of validity of this approximate dynamics are discussed. The effects are illustrated by simulations on several quantum systems.
First measurement of electron temperature from signal ratios in a double-pass Thomson scattering system
Authors: Tojo H. , Ejiri A. , Hiratsuka J. , Yamaguchi T. , Takase Y. , Itami K. , Hatae T.
Published: February 2012

This paper presents an experimental demonstration to determine electron temperature (Te) with unknown spectral sensitivity (transmissivity) in a Thomson scattering system. In this method, a double-pass scattering configuration is used and the scattered lights from each pass (with different scattering angles) are measured separately. Te can be determined from the ratio of the signal intensities without knowing a real chromatic dependence in the sensitivity. Note that the wavelength range for each spectral channel must be known. This method was applied to the TST-2 Thomson scattering system. As a result, Te measured from the ratio (Te,r) and Te measured from a standard method (Te,s) showed a good agreement with 〈|Te,r − Te,s|/Te,s〉 = 7.3%.
Global gyrokinetic particle simulation of toroidal Alfvén eigenmodes excited by antenna and fast ions
Authors: Zhang Wenlu , Holod Ihor , Lin Zhihong , Xiao Yong
Published: February 2012

Linear properties of toroidal Alfvén eigenmode (TAE) is studied in global gyrokinetic particle simulations using both fast ion and antenna excitations. A synthetic antenna provides a precise measurement of the Alfvén continuum gap width and the TAE eigenmode frequency, damping rate, and mode structures. The measured gap width exhibits a linear dependence on the aspect ratio, in agreement to a local analytic theory. The TAE frequency and mode structure excited by fast ions show a significant radial symmetry breaking relative to the ideal magnetohydrodynamic theory due to the non-perturbative contributions from the fast ions. The electromagnetic capability of the global gyrokinetic toroidal code (GTC) is verified through these global gyrokinetic simulations of Alfvén eigenmode in cylindrical and toroidal geometries.
Pinching of ablation streams via magnetic field curvature in wire-array Z-pinches
Authors: Blesener I. C. , Greenly J. B. , Kusse B. R. , Blesener K. S. , Seyler C. E. , Hammer D. A.
Published: February 2012

In this paper, the shapes of the ablation streams in non-imploding cylindrical wire-array Z-pinches are investigated. Experimental observations using axial X pinch imaging show an azimuthal pinching of the streams that appear to depend on the topology of the global magnetic field. With fewer wires and increased interwire spacing, the radial component of the global field is increased; resulting in a stronger pinching of the streams. Computer simulations are used to model the magnetic field development and show that the sparser array has a significantly stronger azimuthal J→×B→ force.
Magnetic behavior of Mn-doped GaN (11¯00) film from first-principles calculations
Authors: Huang GuiQin , Wang JiXia
Published: February 2012

Using first principles calculations based on spin-polarized density functional theory, the magnetic behavior of Mn-doped GaN (11¯00) film is studied. The doping Mn atoms have an attractive pair interaction. Our results give the ground state with antiferromagnetic coupling for Mn-doped GaN (11¯00) film when the nearest neighbor Ga atoms on the surface layer are replaced by Mn atoms, which is contrary to the ferromagnetic coupling when Mn is doped in the bulk GaN. However, in-plane tension and hole doping can switch the magnetic ordering from antiferromagnetism to ferromagnetism, which is important for application in semiconductor spintronics.
Ion current density measurements in a copper vacuum arc with different refractory anode thicknesses
Authors: Beilis I. I. , Koulik Y. , Boxman R. L.
Published: February 2012

The time-dependent ion current density was measured in a hot refractory anode vacuum arc (HRAVA) sustained between a consumed water-cooled cylindrical Cu cathode and non-consumed cylindrical W anodes with thickness d = 5, 10, 15, 20, or 30 mm separated by an h = 10 mm gap. Arc currents of I = 130, 150, 175, and 200 A were applied for a period of 90 s. Ion current density Ji extracted from the plasma was measured using a probe located at varying distances from the electrode axis. The active surface of the probe was oriented to be either perpendicular or parallel to the radially expanding plasma to measure the directed or random component of Ji, respectively. Ji started at arc ignition and grew slowly, passed through a peak, and reached a final steady state level. This level increased with arc current and decreased with probe distance. The time to reach the steady state decreased when d was decreased from 30 to 5 mm, for I = 200 A from 48 to 12 s and for I = 150 A from 69 to 20 s, and weakly depended on probe orientation. Ji to the perpendicular probe significantly exceeded that for the parallel orientation.
Stabilization of mixed-phase structures in highly strained BiFeO3 thin films via chemical-alloying
Authors: Damodaran Anoop R. , Breckenfeld Eric , Choquette Amber K. , Martin Lane W.
Published: February 2012

Chemical-alloying is demonstrated to stabilize the mixed-phase structure of highly strained epitaxial BiFeO3/LaAlO3 (001) heterostructures. Such mixed-phase structures are essential for the large electromechanical responses (4%–5% strains under applied electric field); however, films with thickness exceeding 250 nm undergo an epitaxial breakdown to a non-epitaxial bulk-like rhombohedral-phase. Such an irreversible transformation of the mixed-phase structure limits the magnitude of the net surface displacement associated with these field-induced phase transformations. Using high-resolution x-ray diffraction reciprocal space mapping and scanning-probe-based studies, we show that chemical-alloying of BiFeO3 thin films can stabilize these mixed-phase structures and delay the onset of epitaxial breakdown.
Insights into electrical characteristics of silicon doped hafnium oxide ferroelectric thin films
Authors: Zhou Dayu , Müller J. , Xu Jin , Knebel S. , Bräuhaus D. , Schröder U.
Published: February 2012

Silicon doped hafnium oxide thin films were recently discovered to exhibit ferroelectricity. In the present study, metal-ferroelectric-metal capacitors with Si:HfO2 thin films as ferroelectric material and TiN as electrodes have been characterized with respect to capacitance and current density as functions of temperature and applied voltage. Polarity asymmetry of the frequency dependent coercive field was explained by interfacial effects. No ferroelectric-paraelectric phase transition was observed at temperatures up to 478 K. Clear distinctions between current evolutions with or without polarization switching were correlated to the time competition between the measurement and the response of relaxation mechanisms.
Advance Targeted Transfusion in Anemic Cardiac Surgical Patients for Kidney Protection
Authors: Karkouti Keyvan , Wijeysundera Duminda N. , Yau Terrence M. , McCluskey Stuart A. , Chan Christopher T. , Wong Pui-Yuen , Crowther Mark A. , Hozhabri Siroos , Beattie W. Scott
Published: February 2012

Introduction

: Acute kidney injury (AKI) is a serious complication of cardiac surgery, and preoperative anemia and perioperative erythrocyte transfusion are important risk factors. Prophylactic erythrocyte transfusion in anemic patients may, therefore, protect against AKI.

Methods

: In this unblinded, parallel-group, randomized pilot trial, 60 anemic patients (hemoglobin 10-12 g/dL) undergoing cardiac surgery with cardiopulmonary bypass were randomized (1:1) to prophylactic transfusion (2 units of erythrocytes transfused 1 to 2 days before surgery (n = 29) or standard of care (transfusions as indicated; n = 31). Between-group differences in severity of perioperative anemia, transfusion, and AKI (more than 25% drop in estimated glomerular filtration rate) were measured. The relationships between transfusion, iron levels, and AKI were also measured.

Results

: Perioperative anemia and erythrocyte transfusions were lower in the prophylactic transfusion group--median (25th, 75th percentiles) for nadir hemoglobin was 8.3 (7.9, 9.1) versus 7.6 (6.9, 8.2) g/dL (P = 0.0008) and for transfusion was 0 (0, 2) versus 2 (1, 4) units (P = 0.0002)--but between-group AKI rates were comparable (11 patients per group). In 35 patients with iron studies, perioperative transfusions were directly related to postoperative transferrin saturation (correlation coefficient 0.6; P = 0.0002), and high (more than 80%) transferrin saturation was associated with AKI (5/5 vs. 8/30; P = 0.005), implicating transfusion-related iron overload as a cause of AKI.

Conclusions

: In anemic patients, prophylactic erythrocyte transfusion reduces perioperative anemia and erythrocyte transfusions, and may reduce plasma iron levels. Adequately powered studies assessing the effect of this intervention on AKI are warranted.
Systematic Criteria for Type and Screen Based on Procedure's Probability of Erythrocyte Transfusion
Authors: Dexter Franklin , Ledolter Johannes , Davis Erika , Witkowski Thomas A. , Herman Jay H. , Epstein Richard H.
Published: February 2012

Background

At many hospitals, the type and screen decision is guided by the hospital's maximum surgical blood order schedule, a document that includes for each scheduled (elective) surgical procedure a recommendation of whether a preoperative type and screen be performed. There is substantial heterogeneity in the scientific literature for how that decision should be made.

Methods

Anesthesia information management system data were retrieved from the 160,207 scheduled noncardiac cases in adults of 1,253 procedures at a hospital.

Results

Neither assuming a Poisson distribution of mean erythrocyte units transfused, nor grouping rare procedures into larger groups based on their anesthesia Current Procedural Terminology code, was reliable. In contrast, procedures could be defined to have minimal estimated blood loss (less than 50 ml) based on low incidence of transfusion and low incidence of the hemoglobin being checked preoperatively. Among these procedures, when the lower 95% confidence limit for erythrocyte transfusion was less than 5%, type and screen was shown to be unnecessary. The method was useful based on including multiple differences from the hospital's maximum surgical blood order schedule and clinicians' test ordering (greater than or equal to 29% fewer type and screen). Results were the same with a Bayesian random effects model.

Conclusions

We validated a method to determine procedures on the maximum surgical blood order schedule for which type and screen was not indicated using the estimated blood losses and incidences of transfusion.
Chronic Inflammatory Pure Sensory Polyradiculoneuropathy
Authors: Rajabally Yusuf A. , Wong Siew L.
Published: February 2012

We describe a patient presenting with progressive upper limb numbness and sensory ataxia of the 4 limbs. Motor nerve conduction studies were completely normal. Sensory electrophysiology showed reduced/absent upper limb sensory action potentials (SAPs). In the lower limbs, SAPs were mostly normal. Sensory conduction velocities were normal. Forearm sensory conduction blocks were present for both median nerves on antidromic testing. The maximal recordable sural SAP was preserved in comparison to maximal recordable radial SAP, consistent with an “abnormal radial normal sural” pattern. Somatosensory evoked potentials were unrecordable for tibial and median nerves. Cerebrospinal fluid protein was raised (0.99 g/L). The patient worsened on oral corticosteroids but subsequently made substantial functional recovery on intravenous immunoglobulins. This case is different to those previously reported of sensory chronic inflammatory demyelinating polyradiculoneuropathy, given its exclusive sensory electrophysiologic presentation, presence of predominant upper limb reduced sensory amplitudes, and detection of sensory conduction blocks. These electrophysiologic features were of paramount importance in establishing diagnosis and effective therapy.
Dan Lewis. 30 December 1910 — 30 September 2009
Authors: Casselton Lorna A. , Jones David A.
Published: February 2012

Dan Lewis is best known for his work on plant breeding systems. Self-incompatibility is common in hermaphroditic plants as a mechanism that prevents inbreeding; it may be determined by genes expressed in the haploid gametes (gametophytic) or by those expressed in the diploid tissue that gives rise to gametes (sporophytic). At different times in his career, Lewis contributed to a better understanding of both these systems, but it was his work on the gametophytic system in the evening primrose,
Oenothera organensis
, that broke new ground and enabled him to predict a molecular recognition between different proteins produced in the pollen and style; these proteins were encoded by tightly linked genes at a complex self-incompatibility (
S
) locus. Modern molecular techniques have since confirmed these predictions and revealed the actual nature of the proteins and their interactions. The research began as part of a programme of breeding plants of horticultural and agricultural importance while working at the John Innes Institute, the foremost place to study genetics in the UK at that time. The Institution had William Bateson (FRS 1894) as its first director, followed by Sir Daniel Hall (FRS 1909), who in turn was succeeded in 1939 by Cyril Darlington (FRS 1941). To begin your career there in the 1930s was almost guaranteed to lead to scientific success.
High relatedness in a social amoeba: the role of kin-discriminatory segregation
Authors: Gilbert Owen M. , Strassmann Joan E. , Queller David C.
Published: February 2012

A major challenge for social theory is to explain the importance of kin discrimination for the evolution of altruism. One way to assess the importance of kin discrimination is to test its effects on increasing relatedness within groups. The social amoeba
Dictyostelium discoideum
aggregates to form a fruiting body composed of dead stalk and live spores. Previous studies of a natural population showed that where
D. discoideum
occurs in the soil, multiple clones are often found in the same small soil samples. However, actual fruiting bodies usually contain only one clone. We here performed experiments to gauge the effect of kin-discriminatory segregation on increasing relatedness. We mixed co-occurring clones from this population using a relatedness level found in small soil samples. We found a lower proportion of uniclonal fruiting bodies and a lower level of relatedness compared with natural fruiting bodies. We found that the amount of relatedness increase attributable to kin-discriminatory segregation was small. These findings suggest a relatively minor influence of kin-discriminatory segregation on relatedness in
D. discoideum
. We discuss our results comparing with the results of previous studies, including those of wild clones and laboratory mutants. We ask why wild clones of
D. discoideum
exhibit a low degree of kin-discriminatory segregation, and what alternative factors might account for high relatedness in
D. discoideum
.
Ant workers die young and colonies collapse when fed a high-protein diet
Authors: Dussutour A. , Simpson S. J.
Published: February 2012

A key determinant of the relationship between diet and longevity is the balance of protein and carbohydrate in the diet. Eating excess protein relative to carbohydrate shortens lifespan in solitary insects. Here, we investigated the link between high-protein diet and longevity, both at the level of individual ants and colonies in black garden ants,
Lasius niger
. We explored how lifespan was affected by the dietary protein-to-carbohydrate ratio and the duration of exposure to a high-protein diet. We show that (i) restriction to high-protein, low-carbohydrate diets decreased worker lifespan by up to 10-fold; (ii) reduction in lifespan on such diets was mainly due to elevated intake of protein rather than lack of carbohydrate; and (iii) only one day of exposure to a high-protein diet had dire consequences for workers and the colony, reducing population size by more than 20 per cent.
Critical role of the interleukin‐23//T‐helper 17 cell axis in the pathogenesis of psoriasis
Authors: NAKAJIMA Kimiko
Published: February 2012

Psoriasis is an inflammatory disease with dynamic interactions between the immune system and the skin. Recent studies have demonstrated that the interleukin (IL)‐23//T‐helper (Th)17 cell axis plays an important role in the pathogenesis of psoriasis. Here, the biology and function of Th17 cells as well as the crucial role of IL‐23 in the context of the Th17 cell‐dependent chronic inflammation in psoriatic skins are reviewed. Recent study about the role of the IL‐23//Th17 axis in the pathogenesis of psoriasis‐like lesions in K5.Stat3C transgenic mice is also discussed. This model mouse for psoriasis not only verifies the therapeutic efficacies of biologics that specifically target the IL‐23//Th17 axis, but also clarifies the pathogenesis of psoriasis.
Learning at the digital frontier: a review of digital literacies in theory and practice
Authors: Littlejohn A. , Beetham H. , McGill L.
Published: February 2012

This paper describes a literature review, institutional audit and analysis of practice in the area of digital literacy provision, based on research across the UK Higher Education sector. It concludes that institutions need to place greater value on ‘literacies of the digital’, and better prepare their students and their own organizational processes to thrive in an age of digital knowledge practices. It extends the debate about individual entitlement and provision to ask whether digital literacy offers an opportunity for the academy to redefine its relationship to knowledge in society.
Initial combination of linagliptin and metformin improves glycaemic control in type 2 diabetes: a randomized, double‐blind, placebo‐controlled study
Authors: Haak T. , Meinicke T. , Jones R. , Weber S. , Eynatten M. von , Woerle H.‐J.
Published: February 2012

Aims: To evaluate the efficacy and safety of initial combination therapy with linagliptin plus metformin versus linagliptin or metformin monotherapy in patients with type 2 diabetes.

Methods: In this 24‐week, double‐blind, placebo‐controlled, Phase III trial, 791 patients were randomized to one of six treatment arms. Two free combination therapy arms received linagliptin 2.5 mg twice daily (bid) + either low (500 mg) or high (1000 mg) dose metformin bid. Four monotherapy arms received linagliptin 5 mg once daily, metformin 500 mg or 1000 mg bid or placebo. Patients with haemoglobin A1c (HbA1c) ≥11.0% were not eligible for randomization and received open‐label linagliptin + high‐dose metformin.

Results: The placebo‐corrected mean (95% confidence interval) change in HbA1c from baseline (8.7%) to week 24 was −1.7% (−2.0, −1.4) for linagliptin + high‐dose metformin, −1.3% (−1.6, −1.1) for linagliptin + low‐dose metformin, −1.2% (−1.5, −0.9) for high‐dose metformin, −0.8% (−1.0, −0.5) for low‐dose metformin and −0.6 (−0.9, −0.3) for linagliptin (all p < 0.0001). In the open‐label arm, the mean change in HbA1c from baseline (11.8%) was −3.7%. Hypoglycaemia occurred at a similar low rate with linagliptin + metformin (1.7%) as with metformin alone (2.4%). Adverse event rates were comparable across treatment arms. No clinically significant changes in body weight were noted.

Conclusions: Initial combination therapy with linagliptin plus metformin was superior to metformin monotherapy in improving glycaemic control, with a similar safety and tolerability profile, no weight gain and a low risk of hypoglycaemia.
Chinatown in Washington, DC: The bilingual landscape
Authors: JIA LOU JACKIE
Published: February 2012

ABSTRACT:  Originated as a new approach to multilingualism, research on linguistic landscapes has typically focused on the varieties of language inscribed on the surface of a particular place. As this original conceptualization and its associated methodology have not always sufficed to capture the sociolinguistic complexities of contemporary urban environments, recent researchers have called for a more contextualized approach to linguistic landscapes. Drawing on Lefebvre and Scollon and Scollon, this paper suggests that the linguistic landscapes might be considered with reference to a triadic model of place and spatial representation. This model is applied to reevaluate the bilingual landscape of Washington DC's Chinatown, with a particular focus on the multiple roles played by the English language in shaping and navigating the multilingual environment.