bluuebunny/crossref_metadata_2025 huggingface dataset:
Teaching Genomic Counseling: Preparing the Genetic Counseling Workforce for the Genomic Era
Authors: Hooker Gillian W. , Ormond Kelly E. , Sweet Kevin , Biesecker Barbara B.
Published: February 2014

Genetic counselors have a long‐standing history of working on the clinical forefront of implementing new genetic technology. Genomic sequencing is no exception. The rapid advancement of genomic sequencing technologies, including but not limited to next generation sequencing approaches, across all subspecialties of genetic counseling mandates attention to genetic counselor training at both the graduate and continuing education levels. The current era provides a tremendous opportunity for counselors to become actively involved in making genomics more accessible, engaging the population in decisions to undergo sequencing and effectively translating genomic information to promote health and well‐being. In this commentary, we explore reasons why genomic sequencing warrants particular consideration and put forward strategies for training program curricula and continuing education programs to meet this need.
Patellar dislocation due to iatrogenic quadriceps fibrosis: Results of operative treatment in 54 cases
Authors: Hung Nguyen Ngoc , Tan Do , Do Ngoc Hien Nguyen
Published: February 2014

Objective

To evaluate the clinical and functional results of a surgical treatment of patellar dislocation whose etiology was iatrogenic quadriceps fibrosis in children.

Materials and methods

A prospective study was undertaken from February 2004 to December 2009. The study included 54 pediatric patients (56 knees) that had developed dislocation of the patella after repeated intramuscular injections of antibiotic(s) into the quadriceps muscle. There were 11 males (20.4 %) and 43 females (79.6 %). The patients’ mean age at surgery was 7 years, 9 months (range 6 years, 4 months to 12 years, 6 months). A complete history of each patient was recorded. The affected knees were evaluated preoperatively and postoperatively on the basis of the symptoms, signs, and roentgenographic findings. Patellar dislocation was classified according Bensahel's criteria. All patients had a three-part surgical procedure that combined capsulorrhaphy, quadricepsplasty, and transfer of the vastus medialis oblique to the superior border of the patella.

Results

There has been no poor postsurgical result or recurrence so far; we have noted an ugly scar in nine knees (16.1 %), limitation of the knee flexion in five knees (8.9 %), and loss of extension of 5 °–20 ° in four knees (7.1 %). Overall, we attained excellent results in 39 knees (69.7 %), good results in 13 knees (23.2 %), and fair results in four knees (7.1 %).

Conclusion

In our cases of pediatric dislocation of the patella caused by iatrogenic quadriceps fibrosis, the introduced three-part surgical procedure has shown great success in restoring the realignment mechanism of the patella. The technique is simple, safe, and effective in skeletally immature children.
Co‐occurrence of antisocial behavior and substance use: Testing for sex differences in the impact of older male friends, low parental knowledge and friends' delinquency
Authors: MAdams Tom A. , Salekin Randall T. , Marti C. Nathan , Lester Whiney S. , Barker Edward D.
Published: February 2014

Delinquency and substance use (SU) are commonly comorbid during adolescence. In the present study we investigate this co‐morbidity with 3 main objectives: 1. Evaluate reciprocal relationships between delinquency/SU across early adolescence. 2. Assess the impact of older male friends, low parental knowledge and friends' delinquency on subsequent development and inter‐relationships of delinquency and SU. 3. Evaluate sex differences in these relationships.

We applied cross‐lagged structural equation models to the analysis of a longitudinal sample (n = 3699). Findings demonstrated: (1) At ages 13–14 delinquency predicted SU more so than vice versa but effects became equal between ages 14 and 15. (2) Low parental knowledge and friends' delinquency predicted delinquency and SU. Older male friends predicted ASB. (3) Sex differences were present. For example, in the absence of antisocial friends low parent knowledge at age 12 indirectly predicted increased age 15 SU for girls more than boys.
Growth rate controlled synthesis of hierarchical Bi2S3/In2S3 core/shell microspheres with enhanced photocatalytic activity
Authors: Zhou Juan , Tian Guohui , Chen Yajie , Shi Yunhan , Tian Chungui , Pan Kai , Fu Honggang
Published: February 2014

Core/shell heterostructure composite has great potential applications in photocatalytic field because the introduction of core can remarkably improve charge transport and enhance the electron-hole separation. Herein, hierarchical Bi2S3/In2S3 core/shell structured microspheres were prepared via a simple one-pot hydrothermal process based on different growth rate of the two kinds of sulphides. The results showed that, the as-prepared hierarchical Bi2S3/In2S3 core/shell heterostructure exhibits significant visible light photocatalytic activity for degradation of 2, 4-dichlorophenol. The introduction of Bi2S3 core can not only improve charge transport and enhance the electron-hole separation, but also broaden the visible light response. The hierarchical porous folwer-like shell of In2S3 could increase the specific surface area and remarkably enhanced the chemical stability of Bi2S3 against oxidation.
Linking Pd(ii) and Ru(ii) phthalocyanines to single-walled carbon nanotubes
Authors: d'Ambrosio Primiano , Carchesio Manuela , d'Alessandro Nicola , de la Torre Gema , Torres Tomás
Published: February 2014

The preparation of novel, covalent Pd(ii)-SWCNT and Ru(ii)(bipyridyl)Pc-SWCNT hybrid materials by means of two-step synthetic procedures is described.
Asymmetric hetero-assembly of colloidal nanoparticles through “crash reaction” in a centrifugal field
Authors: Song Sha , Kuang Yun , Luo Liang , Sun Xiaoming
Published: February 2014

Asymmetric hetero-assembly of two kinds of colloidal nanoparticles (NPs) was achieved by “crash reaction” in a density gradient centrifugation system using Au NPs as an example.
Angle-resolved valence shell photoelectron spectroscopy of neutral nanosized molecular aggregates
Authors: Signorell Ruth , Yoder Bruce L. , West Adam H. C. , Ferreiro Jorge J. , Saak Clara-Magdalena
Published: February 2014

Angle-resolved photoelectron spectroscopy opens a new avenue to probe the orbital character of solutes and solvents from the nanoscale to the bulk.
Magnetic edge-states in nanographene, HNO3-doped nanographene and its residue compounds of nanographene-based nanoporous carbon
Authors: Hao Si-Jia , Joly V. L. Joseph , Kaneko Satoshi , Takashiro Jun-ichi , Takai Kazuyuki , Hayashi Hitoshi , Enoki Toshiaki , Kiguchi Manabu
Published: February 2014

The magnetism of HNO3doped nanographene sheets is affected seriously through charge transfer and structural compression, but heating under vacuum leads to the recovery.
Detection of host–guest interactions in clathrates of heterocyclic molecules adsorbed in a porous MOF with Cu2 cluster nodes via vibration spectra and magnetic properties
Authors: Guo Ping-Chun , Chen Tian-Yu , Ren Xiao-Ming , Xiao Chen , Jin Wanqin
Published: February 2014

A 3-D MOF Cu2(EBTC)(H2O)2·[G] was used to encapsulate benzopyrrole, benzofuran and benzothiophene molecules. The host–guest interactions were studied via vibration spectra and magnetic susceptibility.
Chemerin reduces vascular nitric oxide/cGMP signalling in rat aorta: a link to vascular dysfunction in obesity?
Authors: Neves Karla Bianca , Lobato Núbia S. , Lopes Rhéure Alves Moreira , Filgueira Fernando P. , Zanotto Camila Ziliotto , Oliveira Ana Maria , Tostes Rita C.
Published: February 2014

The adipokine chemerin has been implicated in cardiovascular complications associated with obesity and the metabolic syndrome. Chemerin has direct effects on the vasculature, augmenting vascular responses to contractile stimuli. As NO/cGMP signalling plays a role in vascular dysfunction associated with obesity and the metabolic syndrome, we hypothesized that chemerin induces vascular dysfunction by decreasing NO/cGMP signalling. Aortic rings from male Wistar rats (10–12 weeks of age) were incubated with chemerin (0.5 or 5 ng/ml for 1 h) or vehicle and isometric tension was recorded. Vasorelaxation in response to ACh (acetylcholine), SNP (sodium nitroprusside) and BAY 412272 [an sGC (soluble guanylate cyclase) stimulator] were decreased in chemerin-treated vessels. The NOS (NO synthase) cofactor BH4 (tetrahydrobiopterin), an O2− (superoxide anion) scavenger (tiron) and a SOD (superoxide dismutase) mimetic (tempol) abolished the effects of chemerin on ACh-induced vasodilation. eNOS (endothelial NOS) phosphorylation, determined by Western blotting, was increased in chemerin-treated vessels; however, the enzyme was mainly in the monomeric form, with decreased eNOS dimer/monomer ratio. Chemerin decreased the mRNA levels of the rate-limiting enzyme for BH4 biosynthesis GTP cyclohydrolase I. Chemerin-incubated vessels displayed decreased NO production, along with increased ROS (reactive oxygen species) generation. These effects were abrogated by BH4, tempol and L-NAME (NG-nitro-L-arginine methyl ester). sGC protein expression and cGMP levels were decreased in chemerin-incubated vessels. These results demonstrate that chemerin reduces NO production, enhances NO breakdown and also decreases NO-dependent cGMP signalling, thereby reducing vascular relaxation. Potential mechanisms mediating the effects of chemerin in the vasculature include eNOS uncoupling, increased O2− generation and reduced GC activity.
The kinin B1 receptor regulates muscle-specific E3 ligases expression and is involved in skeletal muscle mass control
Authors: Parreiras-e-Silva Lucas T. , Reis Rosana I. , Santos Geisa A. , Pires-Oliveira Marcelo , Pesquero João B. , Gomes Marcelo D. , Godinho Rosely O. , Costa-Neto Claudio M.
Published: February 2014

Regulation of muscle mass depends on the balance between synthesis and degradation of proteins, which is under the control of different signalling pathways regulated by hormonal, neural and nutritional stimuli. Such stimuli are altered in several pathologies, including COPD (chronic obstructive pulmonary disease), diabetes, AIDS and cancer (cachexia), as well as in some conditions such as immobilization and aging (sarcopenia), leading to muscle atrophy, which represents a significant contribution to patient morbidity. The KKS (kallikrein–kinin system) is composed of the enzymes kallikreins, which generate active peptides called kinins that activate two G-protein-coupled receptors, namely B1 and B2, which are expressed in a variety of tissues. The local modulation of the KKS may account for its participation in different diseases, such as those of the cardiovascular, renal and central nervous systems, cancer and many inflammatory processes, including pain. Owing to such pleiotropic actions of the KKS by local modulatory events and the probable fine-tuning of associated signalling cascades involved in skeletal muscle catabolic disorders [for example, NF-κB (nuclear factor κB) and PI3K (phosphoinositide 3-kinase)/Akt pathways], we hypothesized that KKS might contribute to the modulation of intracellular responses in atrophying skeletal muscle. Our results show that kinin B1 receptor activation induced a decrease in the diameter of C2C12 myotubes, activation of NF-κB, a decrease in Akt phosphorylation levels, and an increase in the mRNA levels of the ubiquitin E3 ligases atrogin-1 and MuRF-1 (muscle RING-finger protein-1). In vivo, we observed an increase in kinin B1 receptor mRNA levels in an androgen-sensitive model of muscle atrophy. In the same model, inhibition of the kinin B1 receptor with a selective antagonist resulted in an impairment of atrogin-1 and MuRF-1 expression and IκB (inhibitor of NF-κB) phosphorylation. Moreover, knockout of the kinin B1 receptor in mice led to an impairment in MuRF-1 mRNA expression after induction of LA (levator ani) muscle atrophy. In conclusion, using pharmacological and gene-ablation tools, we have obtained evidence that the kinin B1 receptor plays a significant role in the regulation of skeletal muscle proteolysis in the LA muscle atrophy model.
Application of data mining in multiobjective optimization problems
Authors: Mosavi Amir
Published: February 2014

In the most engineering optimization design problems, the value of objective functions is not clearly defined in terms of design variables. Instead it is obtained by some numerical analysis such as FE structural analysis, fluid mechanic analysis, and thermodynamic analysis, etc. Usually, these analyses are considerably time consuming to obtain a value of objective functions. In order to make the number of analyses as few as possible a methodology is presented as a supporting tool for the meta-modeling techniques. Researches in meta-modeling for multiobjective optimization are relatively young and there is still much to do. It is shown that visualizing the problem on the basis of the randomly sampled geometrical data of CAD and CAE simulation results, in addition to utilizing classification tool of data mining could be effective as a supporting system to the available meta-modeling techniques. To evaluate the effectiveness of the proposed method a study case in 3D wing design is given. Along with this example, it is discussed how effective the proposed methodology could be in the practical engineering problems.
Mathematical methodology for optimization of the clamping forces accounting for workpiece vibratory behaviour
Authors: Chaari Riadh , Abennadher Moez , Louati Jamel , Haddar Mohamed
Published: February 2014

This paper addresses the problem of determining the minimum clamping forces that ensure the dynamic fixturing stability. The clamping force optimization problem is formulated as a bi-level nonlinear programming problem and solved using a computational intelligence technique called particle swarm optimization (PSO). Indeed, we present an innovative simulation methodology that is able to study the effects of fixture-workpiece system dynamics and the continuously change due to material removal on fixturing stability and the minimum required clamping forces during machining. The dynamic behaviour of the fixtured workpiece subjected to time-and space-varying machining loads is simulated using a forced vibration model based on the regenerative vibrations of the cutter and workpiece excited by the dynamic cutting forces. Indeed, Material removal significantly affects the fixture-workpiece system dynamics and subsequently the minimum clamping forces required for achieving fixturing dynamic stability.
Comparison of 1D and 2D models predicting a packed bed drying
Authors: Messai Souad , El Ganaoui Mohamed , Sghaier Jalila , Chrusciel Laurent , Slimane Gabsi
Published: February 2014

A numerical study for the modelling of porous particles packed bed drying in one and two dimensions (1D and 2D) is presented in this work. This model is based on the averaging volume approach using two scale changes. Taking into account the non validity of the thermal equilibrium between the gas phase and the porous particle, a two temperatures model is then developed. The numerical resolution of macroscopic equations describing heat and mass transfer during the drying of a packed bed is carried out by the method of finite volume. Experimental data for spherical porous alumina particles reported in the literature were used for the validation of the model. A good agreement was found. The influence of particles thermophysical properties and operating variables is tested. A set of time-space evolution describes the progression of these variables with time, in the height and radius of the packed bed. The model results allow a better understanding of the heat and mass transfer mechanisms involved in a packed bed drying process.
Influence of parallel vs. perpendicular source geometry on cathodic: Arc efficiency and film quality for generation of ZnO thin films
Authors: Eno D. M. , DeLeon R. L. , Garvey J. F.
Published: February 2014

ZnO films have been grown on Si (111) substrates using a modified PAMBD (pulsed arc molecular beam deposition) reactive cathodic arc source employing either O2, N2, or NH3 as carrier gas. Utilizing new source geometry, a two to three fold improvement in source efficiency has been realized. Scanning electron microscopy analysis confirms that this new source configuration gives a significant reduction in marcoparticle contamination and exhibits good crystalline properties for room temperature deposition. ZnO films were grown with this new source and characterized using X-ray diffraction and X-ray photoelectron spectroscopy.
Influence of roughness in the phase-shifting speckle method: An experimental study with applications
Authors: Werth N. , Salazar-Bloise F. , Koch A.
Published: February 2014

In this paper, a quantification of the influence of roughness in the phase-shifting speckle technique (phase-difference) is presented. For this purpose, a series of experiments were carried out on calibrated samples of different roughness varying the equivalent wavelength Λ, by combining the wavelengths of an argon-ion laser. In order to use this method correctly, on the basis of the phase fringe contrast, a criterion for the minimal Λ (limit) needed for a specific roughness is given. Besides, considering the investigated relation between roughness and effective wavelength as an inverse problem, a procedure to measure the roughness of a surface is proposed. Laboratory experiments to prove the validity of the method are shown.
Geometry of matrix product states: Metric, parallel transport, and curvature
Authors: Haegeman Jutho , Mariën Michaël , Osborne Tobias J. , Verstraete Frank
Published: February 2014

We study the geometric properties of the manifold of states described as (uniform) matrix product states. Due to the parameter redundancy in the matrix product state representation, matrix product states have the mathematical structure of a (principal) fiber bundle. The total space or bundle space corresponds to the parameter space, i.e., the space of tensors associated to every physical site. The base manifold is embedded in Hilbert space and can be given the structure of a Kähler manifold by inducing the Hilbert space metric. Our main interest is in the states living in the tangent space to the base manifold, which have recently been shown to be interesting in relation to time dependence and elementary excitations. By lifting these tangent vectors to the (tangent space) of the bundle space using a well-chosen prescription (a principal bundle connection), we can define and efficiently compute an inverse metric, and introduce differential geometric concepts such as parallel transport (related to the Levi-Civita connection) and the Riemann curvature tensor.
A compact high-performance low-field NMR apparatus for measurements on fluids at very high pressures and temperatures
Authors: Freedman R. , Anand V. , Grant B. , Ganesan K. , Tabrizi P. , Torres R. , Catina D. , Ryan D. , Borman C. , Krueckl C.
Published: February 2014

We discuss an innovative new high-performance apparatus for performing low-field Nuclear Magnetic Resonance (NMR) relaxation times and diffusion measurements on fluids at very high pressures and high temperatures. The apparatus sensor design and electronics specifications allow for dual deployment either in a fluid sampling well logging tool or in a laboratory. The sensor and electronics were designed to function in both environments. This paper discusses the use of the apparatus in a laboratory environment. The operating temperature and pressure limits, and the signal-to-noise ratio (SNR) of the new system exceed by a very wide margin what is currently possible. This major breakthrough was made possible by a revolutionary new sensor design that breaks many of the rules of conventional high pressure NMR sensor design. A metallic sample holder capable of operating at high pressures and temperatures is provided to contain the fluid under study. The sample holder has been successfully tested for operation up to 36 Kpsi. A solenoid coil wound on a slotted titanium frame sits inside the metallic sample holder and serves as an antenna to transmit RF pulses and receive NMR signals. The metal sample holder is sandwiched between a pair of gradient coils which provide a linear field gradient for pulsed field gradient diffusion measurements. The assembly sits in the bore of a low-gradient permanent magnet. The system can operate over a wide frequency range without the need for tuning the antenna to the Larmor frequency. The SNR measured on a water sample at room temperature is more than 15 times greater than that of the commercial low-field system in our laboratory. Thus, the new system provides for data acquisition more than 200 times faster than was previously possible. Laboratory NMR measurements of relaxations times and diffusion coefficients performed at pressures up to 25 Kpsi and at temperatures up to 175 °C with crude oils enlivened with dissolved hydrocarbon gases (referred to as “live oils”) are shown. This is the first time low-field NMR measurements have been performed at such high temperatures and pressures on live crude oil samples. We discuss the details of the apparatus design, tuning, calibration, and operation. NMR data acquired at multiple temperatures and pressures on a live oil sample are discussed.
The Bender-Dunne basis operators as Hilbert space operators
Authors: Bunao Joseph , Galapon Eric A.
Published: February 2014

The Bender-Dunne basis operators, $\mathsf {T}_{-m,n}=2^{-n}\sum _{k=0}^n { n \choose k} \mathsf {q}^k \mathsf {p}^{-m} \mathsf {q}^{n-k}$T−m,n=2−n∑k=0nnkqkp−mqn−k where $\mathsf {q}$q and $\mathsf {p}$p are the position and momentum operators, respectively, are formal integral operators in position representation in the entire real line $\mathbb {R}$R for positive integers n and m. We show, by explicit construction of a dense domain, that the operators $\mathsf {T}_{-m,n}$T−m,n's are densely defined operators in the Hilbert space $L^2(\mathbb {R})$L2(R).
Effect of Ho substitution on structure and magnetic properties of BiFeO3
Authors: Suresh Pittala , Babu P. D. , Srinath S.
Published: February 2014

Structure and magnetic properties of trivalent Ho substituted BiFeO3 (HoxBi1−xFeO3) have been studied for the compositional range x = 0 to 0.2. The structure remains in rhombohedral R3c for x < 0.15, and further increase in x results a structural transition to orthorhombic Pnma. The decrease in Raman modes and the appearance of new mode at 475 cm−1 confirms the structural changes. Ho doping at Bi site breaks the spin cycloid of BiFO3 and leads to the observation of ferromagnetic order at low temperatures. With increase in temperature, the M-H curves exhibit a pinching leading to double hysteresis loops. A minimum is observed in M-T curves for low fields at compensation temperature (ΘC) and HC attains a maximum close to ΘC. Variation of HC with temperature is discussed in terms of a model consisting of two sublattices. The improved magnetic properties achieved by Ho doping enhance the potential of BiFeO3 for multiferroic applications.
Structural phase transformation of nickel nanostructures with synthetic approach conditions
Authors: Behera B. C. , Ravindra A. V. , Padhan P.
Published: February 2014

Dispersed nanostructures of nickel (Ni) have been synthesized by thermal decomposition of nickel-oleate in the presence of 1-octadecene with controlled synthesis temperature. The evolution of face-centered-cubic (fcc) phase with increasing synthesis temperature from 320 to 365 °C leads to structural phase transformation of nickel nanostructures from hexagonal-close-packed (hcp) to fcc through mixed phases. The saturation magnetization (MS) of pure fcc and hcp is ∼37 and ∼0.67 emu/g, respectively. The quenched MS of hcp Ni nanostructure compared to that of the fcc Ni indicates the presence of frustrated or canted spins in it. As the fcc phase fraction increases the MS increases, but the observed MS is significantly larger than the theoretical MS calculated by considering the contribution solely from the pure hcp and fcc Ni. This enhanced MS indicates the presence of exchange coupling between the phases and nanoparticles.
Mixing antiferromagnets to tune NiFe-[IrMn/FeMn] interfacial spin-glasses, grains thermal stability, and related exchange bias properties
Authors: Akmaldinov K. , Ducruet C. , Portemont C. , Joumard I. , Prejbeanu I. L. , Dieny B. , Baltz V.
Published: February 2014

Spintronics devices and in particular thermally assisted magnetic random access memories require a wide range of ferromagnetic/antiferromagnetic (F/AF) exchange bias (EB) properties and subsequently of AF materials to fulfil diverse functionality requirements for the reference and storage. For the reference layer, large EB energies and high blocking temperature (TB) are required. In contrast, for the storage layer, mostly moderate TB are needed. One of the present issues is to find a storage layer with properties intermediate between those of IrMn and FeMn and in particular: (i) with a TB larger than FeMn for better stability at rest-T but lower than IrMn to reduce power consumption at write-T and (ii) with improved magnetic interfacial quality, i.e., with reduced interfacial glassy character for lower properties dispersions. To address this issue, the EB properties of F/AF based stacks were studied for various mixed [IrMn/FeMn] AFs. In addition to EB loop shifts, the F/AF magnetic interfacial qualities and the AF grains thermal stability are probed via measurements of the low- and high-temperature contributions to the TB distributions, respectively. A tuning of the above three parameters is observed when evolving from IrMn to FeMn via [IrMn/FeMn] repetitions.
A comprehensive investigation of poly(vinylidene fluoride-trifluoroethylene-chlorofluoroethylene) terpolymer nanocomposites with carbon black for electrostrictive applications
Authors: Yin Xunqian , Capsal Jean-Fabien , Guyomar Daniel
Published: February 2014

A percolative poly(vinylidene fluoride-trifluoroethylene-chlorofluoroethylene)/carbon black nanocomposite was fabricated via a simple solution blending method. The dielectric properties, mechanical properties, and breakdown strength were comprehensively investigated for electrostrictive applications. The nanocomposites exhibit excellent mechanical properties and dielectric properties with a dielectric permittivity of 140 and a low dielectric loss of 0.05 at 100 Hz. The significant enhancement of dielectric properties was explained by percolation theory, and a percolation threshold of 4.68 wt. % was observed. Breakdown strength results were analyzed by Weibull probability, and the observed inevitable decrease of breakdown strength limits its practical applications.
Mn L2,3-edge X-ray absorption spectroscopic studies on charge-discharge mechanism of Li2MnO3
Authors: Kubobuchi Kei , Mogi Masato , Ikeno Hidekazu , Tanaka Isao , Imai Hideto , Mizoguchi Teruyasu
Published: February 2014

The redox reaction of Mn in Li2MnO3 was studied by X-ray absorption spectroscopy and ab initio multiplet calculation. Associated with the de-intercalation of Li-ion, small but clear spectral changes were observed in Mn-L2,3 X-ray absorption near edge structure (XANES). The systematic ab initio multiplet calculations of Mn-L2,3 XANES revealed that the spectral changes in the experiment could not simply be ascribed to the change of the valency from Mn4+ to Mn5+ but can be explained well by the changes of local atomic structures around Mn4+ due to the Li de-intercalation. Our results suggest that the electronic state of oxygen should change during charging in Li2MnO3.
Determination of the molecular diffusion coefficients in ternary mixtures by the sliding symmetric tubes technique
Authors: Larrañaga Miren , Rees D. Andrew S. , Bou-Ali M. Mounir
Published: February 2014

A new analytical methodology has been developed to determine the diagonal and cross-diagonal molecular diffusion coefficients in ternary mixtures by the Sliding Symmetric Tubes technique. The analytical solution is tested in binary mixtures obtaining good agreement with the results of the literature. Results are presented for the ternary mixture formed by tetralin, isobutylbenzene, and dodecane with an equal mass fraction for all the components (1–1–1) which is held at 25 °C. Diagonal and cross-diagonal coefficients are determined for the three possible orders of components, in order to compare the results with those available in the literature. A comparison with published results shows a good agreement for the eigenvalues of the diffusion matrix, and a reasonable agreement for the diagonal molecular diffusion coefficients.
Dramatic reduction in process temperature of InGaN-based light-emitting diodes by pulsed sputtering growth technique
Authors: Nakamura Eiji , Ueno Kohei , Ohta Jitsuo , Fujioka Hiroshi , Oshima Masaharu
Published: February 2014

P-type doping of GaN by pulsed sputtering deposition (PSD) at a low growth temperature of 480 °C and dramatic reduction in the growth process temperature for InGaN-based light-emitting diodes (LEDs) were achieved. Mg-doped GaN layers grown on semi-insulating GaN at 480 °C exhibited clear p-type conductivity with a hole concentration and mobility of 3.0 × 1017 cm−3 and 3.1 cm2 V−1 s−1, respectively. GaN/In0.33Ga0.67N/GaN LEDs fabricated at 480 °C showed clear rectifying characteristics and a bright electroluminescence emission near 640 nm. These results indicate that this low temperature PSD growth technique is quite promising for the production of nitride-based light-emitting devices on large-area glass substrates.
Quantum calculations of the carrier mobility: Methodology, Matthiessen's rule, and comparison with semi-classical approaches
Authors: Niquet Yann-Michel , Nguyen Viet-Hung , Triozon François , Duchemin Ivan , Nier Olivier , Rideau Denis
Published: February 2014

We discuss carrier mobilities in the quantum Non-Equilibrium Green's Functions (NEGF) framework. We introduce a method for the extraction of the mobility that is free from contact resistance contamination and with minimal needs for ensemble averages. We focus on silicon thin films as an illustration, although the method can be applied to various materials such as semiconductor nanowires or carbon nanostructures. We then introduce a new paradigm for the definition of the partial mobility μM associated with a given elastic scattering mechanism “M,” taking phonons (PH) as a reference (μM−1=μPH+M−1−μPH−1). We argue that this definition makes better sense in a quantum transport framework as it is free from long range interference effects that can appear in purely ballistic calculations. As a matter of fact, these mobilities satisfy Matthiessen's rule for three mechanisms [e.g., surface roughness (SR), remote Coulomb scattering (RCS) and phonons] much better than the usual, single mechanism calculations. We also discuss the problems raised by the long range spatial correlations in the RCS disorder. Finally, we compare semi-classical Kubo-Greenwood (KG) and quantum NEGF calculations. We show that KG and NEGF are in reasonable agreement for phonon and RCS, yet not for SR. We discuss the reasons for these discrepancies.
Excess iron deintercalation induced superconductivity in Fe(Te, Se) and Fe(Te, S) via sulfur annealing
Authors: Deguchi K. , Yamashita A. , Yamaki T. , Hara H. , Demura S. , Denholme S. J. , Fujioka M. , Okazaki H. , Takeya H. , Yamaguchi T. , Takano Y.
Published: February 2014

We discovered a novel annealing method for Fe-chalcogenide superconductors. It was found that sulfur annealing deintercalated excess Fe via formation of FeS2. Due to its specifics, sulfur annealing is applicable when preparing Fe-chalcogenide-based wires or cables.
Optical properties of tensile-strained and relaxed Ge films grown on InGaAs buffer
Authors: Volodin V. A. , Sokolov L. V. , Pytyato M. A. , Petikov N. I. , Stoffel M. , Rinnert H. , Vergnat M.
Published: February 2014

GeO2/Ge/InxGa1−xAs heterostructures grown on (100) GaAs substrates were studied using Raman spectroscopy and photoluminescence (PL) spectroscopy. Both nearly pseudomorphic tensile-strained and nearly completely relaxed Ge films were grown and studied. The maximum tensile strain for Ge films with a thickness of ≈7 nm reaches 2.25%. PL data confirm the conclusions that the band gap offset of Ge/InxGa1−xAs is sensitive to the polarity of the bonds at the interface, and also to a parameter of x and the relaxation of strain. Depending on these parameters, the Ge/InxGa1−xAs may be type-I or type-II heterostructures.
Persistent currents in absence of magnetic field in graphene nanorings: The ambiguous role of inter valley scattering
Authors: Benjamin Colin , Jayannavar A. M.
Published: February 2014

Persistent currents can arise in normal-metal rings due to a magnetic flux threading the ring in equilibrium. However, can persistent currents arise in absence of magnetic flux in the same normal-metal rings? Yes they can but in a non-equilibrium set-up. This is known as current magnification. In this work, we show that current magnification can be seen in graphene nanorings. Further, graphene can have electrons polarized with a valley quantum number. Electron scattering between valleys can have a non-trivial effect on these persistent currents including inducing a sign change and generating them for parameters where none existed to begin with.
Comparative life cycle analysis for gasification-based hydrogen production systems
Authors: Muresan M. , Cormos C. C. , Agachi P. S.
Published: February 2014

Hydrogen is expected to play a significant role in the future energy systems, given the global increase in energy demand, which is driven by the accelerated growth of the world's population, the on-going industrial development and urbanization as well as the higher standards of living and education. In this paper, the life cycle assessment (LCA) methodology is used to evaluate the environmental impact of two different gasification based hydrogen production technologies: hydrogen production by biomass steam gasification in a dual fluidized bed reactor system (DFB) and hydrogen production by gasification of coal and biomass using entrained flow technology (EF). For both hydrogen production pathways the gasification plant, raw materials production, pre-processing, and transportation are included in the life cycle assessment and also hydrogen delivery to consumers. The DFB cases have lower global warming potential than the EF cases. Also the abiotic depletion fossil potential and the human toxicity potential are lower. The acidification and eutrophication potentials are lower for the EF cases.
Infrared measurements and simulations of metal meshes in a focused beam
Authors: Stewart K. P. , Möller K. D. , Grebel H.
Published: February 2014

Infrared transmittance measurements of quasioptical filters are often restricted to a focused beam due to the optical design of the spectrometer. In contrast, numerical simulations assume an incident plane wave, which makes it difficult to compare theory with experimental data. We compare transmittance measurements with numerical simulations of square arrays of circular holes in 3-μm thick Cu sheets at angles of incidence from 0° to 20° for both s and p polarizations. These simple structures allow detailed tests of our electromagnetic simulation methods and show excellent agreement between theory and measurement. Measurements in a focused beam are accurately simulated by combining plane wave calculations over a range of angles that correspond to the focal ratio of the incident beam. Similar screens have been used as components of narrow bandpass filters for far-infrared astronomy, but these results show that the transmittance variations with angle of incidence and polarization limit their use to collimated beams at near normal incidence. The simulations are accurate enough to eliminate a costly trial-and-error approach to the design of more complex and useful quasioptical infrared filters and to predict their in-band performance and out-of-band blocking in focused beams.
Helix–loop–helix/basic helix–loop–helix transcription factor network represses cell elongation in
Arabidopsis
through an apparent incoherent feed-forward loop
Authors: Zhiponova Miroslava K. , Morohashi Kengo , Vanhoutte Isabelle , Machemer-Noonan Katja , Revalska Miglena , Van Montagu Marc , Grotewold Erich , Russinova Eugenia
Published: February 2014

Significance

Our work provides an insight into the complex network of basic helix–loop–helix (bHLH)/helix–loop–helix (HLH) transcription factors that regulates cell elongation. An unknown network motif (an incoherent feed-forward loop) has been discovered that was established by two negative regulators of brassinosteroid responses, namely the HLH transcription factor INCREASED LEAF INCLINATION1 BINDING bHLH1 (IBH1) and its unidentified homolog, IBH1-LIKE1 (IBL1). We also suggest that IBH1 and IBL1 coexist with PHYTOCHROME-INTERACTING FACTOR 4 (another key regulator of cell elongation) in transcriptional complexes.
The Limits of Turkish–Iranian Cooperation, 1974–80
Authors: Kayaoğlu Barın
Published: February 2014

Why did Turkey and Iran fail to become close partners in the 1970s even though they had compelling reasons to do so? This article argues that mutual distrust between Turkish and Iranian leaders, domestic turmoil in the two countries, and diverging geostrategic priorities undermined Ankara and Tehran's efforts to deepen their relations. While the shah of Iran saw his country as the policeman of the Persian Gulf and the Middle East, successive governments in Turkey continued to look west for their security. As economic and political turmoil engulfed the two countries, leading to a revolution in Iran in 1979 and a coup in Turkey in 1980, Iranian and Turkish leaders could not forge a lasting partnership.
A new and standardized method to sample and analyse vitreous samples by the Cellient® automated cell block system
Authors: Van Ginderdeuren Rita , Van Calster Joachim , Stalmans Peter , Van den Oord Joost
Published: February 2014

Purpose

In this prospective study, a universal protocol for sampling and analysing vitreous material was investigated. Vitreous biopsies are difficult to handle because of the paucity of cells and the gelatinous structure of the vitreous. Histopathological analysis of the vitreous is useful in difficult uveitis cases to differentiate uveitis from lymphoma or infection and to define the type of cellular reaction.

Methods

Hundred consecutive vitreous samples were analysed with the Cellient® tissue processor (Hologic). This machine is a fully automated processor starting from a specified container with PreservCyt® (fixative fluid) with cells to paraffin. Cytology was compared with fixatives Cytolyt® (contains a mucolyticum) and PreservCyt®. Routine histochemical and immunostainings were evaluated.

Results

In 92% of the cases, sufficient material was found for diagnosis. In 14%, a Cytolyt® wash was necessary to prevent clotting of the tubes in the Cellient® due to the viscosity of the sample. In 23%, the diagnosis was an acute inflammation (presence of granulocytes); in 33%, chronic active inflammation (presence of T lymphocytes); in 33%, low‐grade inflammation (presence of CD68 cells, without T lymphocytes); and in 3%, a malignant process.

Conclusion

A standardized protocol for sampling and handling vitreous biopsies, fixing in PreservCyt® and processing by the Cellient® gives a satisfactory result in morphology, number of cells and possibility of immuno‐histochemical stainings. The diagnosis can be established or confirmed in more than 90% of cases.
The revised ghent nosology; reclassifying isolated ectopia lentis
Authors: Chandra A. , Patel D. , Aragon‐Martin J.A. , Pinard A. , Collod‐Béroud G. , Comeglio P. , Boileau C. , Faivre L. , Charteris D. , Child A.H. , Arno G.
Published: February 2014

Inherited ectopia lentis (EL) is most commonly caused by Marfan syndrome (MFS), a multisystemic disorder caused by mutations in FBN1. Historically the diagnosis for patients with EL who have no systemic features of MFS is isolated EL (IEL). However, the Ghent nosology for MFS was updated in 2010 and made some important alterations. In particular, patients with EL and a FBN1 mutation are now categorically diagnosed with MFS, if their mutation has previously been described with aortic dilation/dissection. This carries significant systemic implications, as many patients previously diagnosed with IEL are now reclassified. We provide a review of all published cases of IEL caused by FBN1 mutations over the last 20 years to assess what impact the new Ghent nosology has on these. Indeed, 57/123 probands (46.3%) are now classified as MFS according to the revised Ghent nosology and 37/96 mutations (38.5%) reported to cause isolated EL have also been found in patients with aortic dilation/dissection. These findings suggest that EL caused by mutations in FBN1 is actually part of a spectrum of fibrillinopathies with MFS, and the term ‘IEL’ should be avoided in such cases.
Electrophysiological Phenotypes of MeCP2 A140V Mutant Mouse Model
Authors: Ma Lu‐Yao , Wu Chen , Jin Yu , Gao Ming , Li Guo‐Hui , Turner Dharshaun , Shen Jian‐Xin , Zhang Shi‐Jiang , Narayanan Vinodh , Jentarra Garilyn , Wu Jie
Published: February 2014

Aims

MeCP2 gene mutations are associated with Rett syndrome and X‐linked mental retardation (XLMR), diseases characterized by abnormal brain development and function. Recently, we created a novel MeCP2 A140V mutation mouse model that exhibited abnormalities of cell packing density and dendritic branching consistent with that seen in Rett syndrome patients as well as other MeCP2 mutant mouse models. Therefore, we hypothesized that some deficits of neuronal and synaptic functions might also be present in the A140V mutant model.

Methods

Here, we tested our hypothesis in hippocampal slices using electrophysiological recordings.

Results

We found that in young A140V mutant mice (3‐ to 4‐week‐old), hippocampal CA1 pyramidal neurons exhibited more positive resting membrane potential, increased action potential (AP) firing frequency induced by injection of depolarizing current, wider AP duration, and smaller after hyperpolarization potential compared to neurons prepared from age‐matched wild‐type mice, suggesting a neuronal hyperexcitation. At the synaptic level, A140V mutant neurons exhibited a reduced frequency of spontaneous IPSCs (inhibitory postsynaptic potentials) and an enhanced probability of evoked glutamate release, both suggesting neuronal hyperexcitation. However, hippocampal CA1 long‐term potentiation was not significantly different between A140V and WT mice. In adult mice (11‐ to 13‐month‐old), in addition to neuronal hyperexcitation, we also found significant deficits of both short‐term and long‐term potentiation of CA3‐CA1 synapses in A140V mice compared to WT mice.

Conclusions

These results clearly illustrate the age‐dependent abnormalities of neuronal and synaptic function in the MeCP2 A140V mutant mouse model, which provides new insights into the understanding of the pathogenesis of Rett syndrome.
Predicting postoperative mortality after colorectal surgery: a novel clinical model
Authors: van der Sluis F. J. , Espin E. , Vallribera F. , de Bock G. H. , Hoekstra H. J. , van Leeuwen B. L. , Engel A. F.
Published: February 2014

Aim

The aim of this study was to develop and externally validate a clinically, practical and discriminative prediction model designed to estimate in‐hospital mortality of patients undergoing colorectal surgery.

Method

All consecutive patients who underwent elective or emergency colorectal surgery from 1990 to 2005, at the Zaandam Medical Centre, The Netherlands, were included in this study. Multivariate logistic regression analysis was performed to estimate odds ratios (ORs) and 95% confidence intervals (CIs) linking the explanatory variables to the outcome variable in‐hospital mortality, and a simplified Identification of Risk in Colorectal Surgery (IRCS) score was constructed. The model was validated in a population of patients who underwent colorectal surgery from 2005 to 2011 in Barcelona, Spain. Predictive performance was estimated by calculating the area under the receiver operating characteristic curve.

Results

The strongest predictors of in‐hospital mortality were emergency surgery (OR = 6.7, 95% CI 4.7–9.5), tumour stage (OR = 3.2, 95% CI 2.8–4.6), age (OR = 13.1, 95% CI 6.6–26.0), pulmonary failure (OR = 4.9, 95% CI 3.3–7.1) and cardiac failure (OR = 3.7, 95% CI 2.6–5.3). These parameters were included in the prediction model and simplified scoring system. The IRCS model predicted in‐hospital mortality and demonstrated a predictive performance of 0.83 (95% CI 0.79–0.87) in the validation population. In this population the predictive performance of the CR‐POSSUM score was 0.76 (95% CI 0.71–0.81).

Conclusions

The results of this study have shown that the IRCS score is a good predictor of in‐hospital mortality after colorectal surgery despite the relatively low number of model parameters.
Assessment of Atrial Electromechanical Delay and P‐Wave Dispersion in Patients with Psoriasis
Authors: Yildiz Abdulkadir , Ucmak Derya , Oylumlu Mustafa , Akkurt Meltem Z. , Yuksel Murat , Akil Mehmet Ata , Acet Halit , Polat Nihat , Aydin Mesut , Bilik M. Zihni
Published: February 2014

Background

In this study, we sought to evaluate atrial electromechanical properties and conduction homogeneity by tissue Doppler imaging and electrocardiography in patients with psoriasis.

Methods

Thirty‐four patients with psoriasis and 30 age‐ and gender‐matched healthy controls were included in the study. Atrial electromechanical coupling intervals were assessed by means of tissue Doppler echocardiography and P‐wave dispersion (Pd) was calculated from electrocardiogram.

Results

A total of 64 subjects (33 male) with a mean age of 36.8 ± 11.9 years were included in the study. Basal characteristics were similar between 2 groups. Intra‐atrial (15 ± 7 ms vs. 12 ± 5 ms, P = 0.009) and inter‐atrial (28 ± 7 ms vs. 23 ± 7 ms, P = 0.002) electromechanical delays were significantly higher in patients with psoriasis compared with control groups. P‐maximum (112 ± 16 ms vs. 103 ± 8 ms, P = 0.006) and Pd (35 ± 9 ms vs. 20 ± 6 ms, P < 0.001) were also prolonged in patients with psoriasis.

Conclusion

This study demonstrated that atrial electromechanical coupling intervals and P‐wave dispersion were prolonged in patients with psoriasis, which may cause an increased risk of atrial fibrillation in this patient group.
Pulse‐Wave Doppler Interrogation of the Abdominal Aorta: A Window to the Left Heart and Vasculature
Authors: Fadel Bahaa M. , Bakarman Hatem , Al‐Admawi Mohamad , Bech‐Hanssen Odd , Di Salvo Giovanni
Published: February 2014

Systematic imaging of the abdominal aorta during transthoracic echocardiography is advocated as a useful screening tool for aortic aneurysms. The addition of pulse Doppler interrogation to the two‐dimensional imaging can be highly valuable and provides incremental hemodynamic information regarding a wide spectrum of diseases that involve the left heart, aorta, and vasculature. In this manuscript, we review the usefulness of pulse Doppler recording of the abdominal aorta and provide case examples of its value in various disease states.