bluuebunny/crossref_metadata_2025 huggingface dataset:
Donor-Acceptor Pair Recombination in the Ordered Vacancy Compound CuIn5Te8
Authors: Rincón Carlos , Marín Giovanni , Hernández Elvis , Wasim Syed M. , Pérez Gerardo Sánchez , Galibert Jean
Published: March 2014

The photoluminescence (PL) spectra of the ordered vacancy compound CuIn5Te8 was measured as a function of temperature and excitation power intensity. The PL spectra show a band centered around 1.03 eV at excitation intensity of 0.3 W that shifts to higher energies with increasing excitation intensity and with decreasing temperature. The variation of the PL intensity of this band with excitation power is sublinear. Both these facts indicate that this is due to a donor-acceptor pair recombination. From the shift of this band to higher energies with P and the thermal quenching of the PL band, donor and acceptor levels with activation energy of 0.02 and 0.08 eV, respectively, were estimated.
Computer modeling and visualization of hidden defects in thin film solar cells on CuInSe2 and Cu(In,Ga)Se2
Authors: Medvedkin Gennadiy A. , Wennerberg Johan
Published: March 2014

The laser scanning technique was used to realize two- and three-dimensional optoelectronic images of polycrystalline solar cells based on thin films of CuInSe2 and CuInGaSe2. Topograms obtained with the aid of the laser-beam-induced current and computer modeling reveal microregions with reduced photovoltaic efficiency and provide a detailed picture of distribution of hidden inhomogeneities over the entire active surface of the solar cells. Gradation of the microdefects with intensity and size has been achieved using post-experimental graphic and false-color processing of the obtained three-dimensional images.
The Simulation of Phase Matched Three-Frequency Mode Interaction in Nonlinear Optical Nanostructures
Authors: Voevodin Valery , Leontieva Olga
Published: March 2014

Software has been developed to simulate nonlinear optical processes in waveguide nanostructures. Some phase matched solutions for backward parametric oscillation (BWO) in multilayer quantum-well ZnGeP2-CdGeP2 waveguides have been calculated as a concrete example.
A New Air-Bridge Gate Ga0.51In0.49P/In0.15Ga0.85As Pseudomorphic Transistor
Authors: Chang Wen-Lung , Liu Wen-Chau , Lour Wen-Shiung , Wang Wei-Chou , Pan His-Jen , Thei Kong-Beng
Published: March 2014

A new high-performance Ga0.51In0.49P/In0.15Ga0.85As pseudomorphic heterostructure field-effect transistor (PHFET), based on a novel airbridge-gate structure with multiple piers, has been studied. Due to the employment of high Schottky barrier GalnP layer and the newly designed double delta-doped sheets (D3S) InGaAs channel, the high gate-to-drain breakdown voltage and broad and linear transconductance are obtained simultaneously. Also, the use of airbridge-gate technique may improve the DC and RF characteristics of device by suppressing the gate leakage current and reducing the parasitic capacitance.
XANES Study of CuInSe2 and In - rich Phases in the Cu-In-Se System
Authors: Bacewicz Rajmund , Wolska Anna , Filipowicz Jerzy , Ławniczak-Jabłońska Krystyna , Attenkofer Klaus
Published: March 2014

X-ray absorption near edge structure (XANES) of CuInSe2 and In-rich phases like Cu2In4Se7, CuIn3Se5 and CuIn5Se5 is investigated. Absorption at the K edges of Cu and Se and the L1 edge of In has been measured using synchrotron radiation. CuInSe2 spectra are interpreted in terms of the local densities of states in the conduction band and within the real-space multiple-scattering approach. Comparison of spectra for other phases shows changes in p-like densities of states with increasing In content.
II-III2-VI4 Compounds: Technology, Physical Properties and Application
Authors: Georgobiani Anatoly N. , Tagiev Bahadur G. , Tagiev Oktay B. , Djabbarov Rasim B. , Musaeva Nahida N. , Kasumov Ulvi F.
Published: March 2014

Semiconductors with the common composition II-III2-VI4 (where II are divalent cathions; III – trivalent cathions and VI – chalcogenides) are perspective materials for optoelectronics. The electrical properties, luminescence, photoconductivity and thermally stimulated depolarization of these compounds have been investigated MnGa2Se4, MnGa2S4, MnIn2S4, MnGaInS4 and PbGa2Se4 compounds possess high photosensitivity. CaGa2S4 doped with rare-earth elements have been found to be effective luminescent semiconductor materials.
Crystal Growth, Structural and Optical Characterization of the Ordered Vacancy Compounds of the I-III3-VI5 and I-III5-VI8 Families
Authors: Marín Giovanni , Marquez Rigoberto , Guevaraba Rafael , Wasim Syed M. , Delgado Jóse M. , Rincón Carlos , Pérez Gerardo Sánchez , Molina Idelfonzo , Bocaranda Pablo
Published: March 2014

A comparative study of the crystal structure and band gap of the 1:1:2, 1:3:5, and 1:5:8 phases of Cu-In-Se, Cu-Ga-Se, CuIn-Te, and Cu-Ga-Te ternary systems has been made. Attempt is made to explain the observed change in the band gap of these systems due to the shift of the conduction band minimum and valence band maximum caused by the p-d interband repulsion originating from the (IIICu
2+ + 2 VCu
-) defect pair.
Effects of Ce Doping on Phosphor Characteristics of CaGa2S4:Eu
Authors: Kato Ariyuki , Nadjafov Khikmet , Hayashi Ryuichiro , Matsumoto-Aoki Tamao , Yamazaki Makoto , Tagiev Bakhadur , Tagiev Oktai , Dzhabbarov Rasim , Bayramov Ayaz , Mamedov Nazim , Iida Seishi
Published: March 2014

Luminescence characteristics of Ce and Eu co-doped CaGa2S4 have been investigated for the first time. All co-doped samples showed the emission from Eu centers having a peak energy of ∼2.22 eV and they were found to have quantum efficiency values less than 30% for Eu doped sample under 441.6 nm excitation. Thermoluminesence was observed for all co-doped samples. These facts seem to indicate the existence of traps, which may mask the energy transfer from Ce to Eu in co-doped samples. Analyses of the measured transient thermoluminescence (TTL) showed two activation energies, ∼0.2 eV and ∼0.9 eV for most co-doped samples. A model where one trap level participates in two different activation processes is proposed to explain these two activation energies.
Magnetic Materials in Photonic Crystals
Authors: Kee Chul-Sik , Choi Young Kyoung , Kim Jae-Eun , Park Hae Yong , Lim H.
Published: March 2014

We studied magnetic materials in one-dimensional photonic crystals considering both dielectric constant and magnetic permeability, as an example. The analytical expressions are found not only for the edge frequencies of omnidirectional reflection band's (ORB's) but also for the equiomnidirectional contours of the ORB's. The ORB's can always exist in a periodic array of two alternating layers with different wave impedance although both layers have the same index of refraction. The wider ORB can be easily achieved by the use of magnetic permeability. The dielectric constant and the magnetic permeability have the similar effect on the frequency of defect modes.
Solubility Range, Lattice Constant and Energy Band Gap of a New Quaternary Solid Solution Semiconductor Pb1-xMgxSi1-ySey for Mid-Infrared Laser
Authors: Abe Seishi , Masumoto Katashi
Published: March 2014

We have investigated a new quaternary solid solution semiconductor Pb1-x
Mg
x
S1-y
Se
y
in bulk substance. The solubility limits of Mg in Pb1-x
Mg
x
S1-y
Se
y
system were varied from 0.03 to 0.07 under the fixed composition y at 1000 °C, and the typical limit of Mg in the system was 0.05 in Pb1-x
Mg
x
S ternary solid solution. The lattice constants of Pb1-x
Mg
x
S1-y
Se
y
solid solution were changed from 5.922 to 6.120 Å. The relation between the lattice constant L and the composition x in Pb1-x
Mg
x
S ternary solid solution was expressed as L=5.936-0.320x (x≦0.05). The energy band gaps were linearly increased in proportion to the Mg concentration x within the solubility range, and the relation between the energy band gap E

g
and the composition x in Pb1-x
Mg
x
S ternary solid solution was expressed as E

g
=0.42+1.23x+3.75x
2 (x≦0.05).
A Vertical-cavity Surface-emitting Laser with Stable Polarization
Authors: Chen Chih-Cheng , Yang Ying-Jay , Lin Ching-Yen , Shieh Kuang-Yeu , Huang Hsing-Lu
Published: March 2014

We report that a VCSEL operated in stable polarization was obtained with an intrinsic anisotropic semiconductor distributed Bragg reflector (DBR) grown on a (001) on-axis substrate by molecular beam epitaxy (MBE). All the VCSELs, with a square or a rectangular active region oriented in either the [011] or [011̄] direction, exhibited a stable polarization state toward the [011] direction.
Absorption Edge and Magnetic Behaviour of a New Hexagonal System
Authors: Sagredo V. , Attolini G. , Besagni T.
Published: March 2014

Single crystals of Cd1-xMnxInGaS4 with 0.2 ≤ x ≤ 0.9 were grown for the first time by the chemical transport method. The energy gap from the absorption spectra shows a concentration dependence between Eg=2.29 eV for x = 0.4 and Eg=2.12 eV for x = 0. 9.The temperature dependence of the optical energy gap is well represented by the Varshni equation.The temperature dependence of the inverse susceptibility in the high temperature range (80-300K) displayed a Curie-Weiss behaviour for all x values. The paramagnetic Curie temperatures were all negative indicating that the dominant magnetic interactions between the Mn ions are antiferromagnetic.
Effect of Crystalline Electric Field on Magnetic Anisotropy of Nd2BaNiO5
Authors: Okazaki Makoto , Shouren Haruki , Oohigashi Masafumi , Tanaka Norikazu , Motizuki Kazuko
Published: March 2014

We have investigated the magnetic anisotropy energy of antiferromagnetic Nd2BaNiO5 (T

N
=48K) caused by the crystalline electric field. For the Ni2+ ion, by calculating the crystalline electric field at Ni ion site, the energy level splitting of the orbital state of Ni2+ ion (3F) has been obtained. We have derived the Pryce's spin Hamiltonian and evaluated the single-ion-type anisotropy constants. This result shows that the easy direction of the spin moment of Ni2+ ion is parallel to the a-axis. For the Nd3+ ion the crystalline electric field at Nd ion site has been calculated. By the use of an operator equivalents method, we have obtained the effective Hamiltonian for the total angular momentum J of Nd3+ ion (4I9/2). The result indicates that the easy direction of Nd's magnetic moment (=-g

J
µB
J) is parallel to the c-axis. These calculated results are discussed in connection with observations.
Electronic Structure of Mn Doped Diluted Magnetic Semiconductors
Authors: Ueda Shigenori , Suga Shigemasa , Iwasaki Takeshi , Sekiyama Akira , Imada Shin , Sattoh Yuji , Takeyama Shojino
Published: March 2014

We have measured the Mn 2p core absorption spectra of diluted magnetic semiconductors (DMS's) Hg1-x-yCdxMnyTe. We then performed the Mn 2p-3d resonance photoemission in order to reveal the Mn 3d electronic structures. The Mn 3d spectra have features similar to the Mn 3d spectra of other II-VI group DMS's with higher Mn concentration, which were reported by previous Mn 3p-3d resonance photoemission studies. Slight changes with Cd doping were observed in the Mn 3d photoemission and 2p absorption spectra.
Characterization of Lead-doped Strontium Bismuth Tantalate Ferroelectric Ceramics
Authors: Lu Chung-Hsin , Chen Yi-Chou
Published: March 2014

The preparation and ferroelectric properties of layered ferroelectric lead-doped strontium bismuth tantalate (SrBi2Ta2O9) were investigated. The formation of solid solutions of lead-doped SrBi2Ta2O9 was corroborated, in this study. Adding excess bismuth oxide in prepared specimens profoundly enhanced their sinterability. The degree of c-axis preferred orientation of the sintered ceramics decreased with an increase in the lead content of lead-doped SrBi2Ta2O9. The lead-doped specimens exhibited ferroelectric properties with well saturated P-E loops. Both the remanent polarization and dielectric constant increased with the doping amount of lead cations.
Electronic and Magnetic Properties of Fe2+xV1-xZ (Z=Al, Ga)
Authors: Fujlla Shinpei , Ienaga Youichi , Ishida Shoji , Asano Setsuro
Published: March 2014

Heusler-type pseudoternary alloys Fe2+x
V1-x
Z (Z=Al, Ga) have been investigated because of a curious resistance maximum near the Curie temperature. Near the x=0 composition, these alloys exhibit a strong, semiconductor-like anomaly. To gain more insight into the mechanism of this anomalous behavior, band calculations (LMTO-ASA) have been performed for several x values. In general, the obtained magnetic structures are consistent with experimental results. In particular, with respect to electronic structures at x=0, our results indicate that the electron number of atomic sites is strongly correlated with the creation of a band gap.
Magnetic Viscosity of NdFe11TiNx Thin Films
Authors: Fang Jau-Shiung , Jian Miaw-Ru , Chin Tsung-Shune , Zhang Hong-Wei , Shen Bao-Gen
Published: March 2014

NdFe11TiNx thin films were prepared by dc magnetron sputtering the NdFe11Ti films on Si (100) at 45°°C followed by subsequent nitriding. Magnetic activation volume was evaluated by measuring the coercivity as a function of the sweep rate of the applied field and also through magnetic viscosity and remanence measurement. The estimated activation volumes are 1.32×10-17 cm3 and 4.76×10-17 cm3, respectively. At room temperature, the maximum values of magnetic viscosity coefficient and irreversible susceptibility are 23.07 G/sec and 34.74 G/Oe, respectively, both occur at an applied field equal to coercivity. These parameters compare well other rare earth magnets and films.
Study on High Density Erasable Optical Discs Based on Ag-In-Sb-Te Optical Phase Change Recording Material
Authors: Ku Shih-Liang , Cheng Yu-Han , Tseng Bae-Heng , Hwang Huey-Liang
Published: March 2014

Ag-In-Sb-Te multinary alloy is one of the most challenging materials for use in the phase change recording media. In this investigation, an Ag-In-Sb-Te recording film was sandwiched between two ZnS–SiO2 layers. And the layer structure of the phase change disc was polycarbonate substrate / ZnS:SiO2 100 nm / Ag-In-Sb-Te 18 nm / ZnS:SiO2 20 nm / Al-Cr 95 nm, which was determined from the optical simulation with the results confirmed from the analyses. Finally, a disc with good optical recording properties was performed.
Different Crystal Growth Pattern in (RE)Ba-Cu-O Single Grained Samples, where RE=Y, Nd
Authors: Chen In-Gann , Liu Haw-Jer , Wu Maw-Kuan
Published: March 2014

Recent studies indicated that single grained samples of (RE)BCO system, where RE=Y, Sm, Nd, etc., can be produced. These single grained samples exhibits a significantly better Jc(H,T) properties than multiple grained samples due to the elimination of grain boundary weak-link problem and improvement of flux pinning mechanism. In this study, we have conducted a study on the crystal growth morphology and crystal quality of Y-Ba-Cu-O and Nd-Ba-Cu-O systems. Our studies show that the growth patterns in different systems are quite different For example, the growth pattern in Nd-Ba-Cu-O single-grain sample is not symmetrical as that observed in Y-Ba-CuO sample. One possible reason for this difference is due to the fact that Nd-Ba-Cu-O system has a higher [RE] solubility in Ba-Cu rich liquid than that of Y-Ba-Cu-O system which causes a higher growth rate on the solid/liquid interface. The other possible reason is the use of different seed for nucleation. The Tc of these samples were measured and compared with each others to correlate their growth conditions.
Research of Domain Structure of ZnSnC2
5 - Compounds
Authors: Voevodin Valery , Voevodina Olga , Morozov Alexander
Published: March 2014

Taking thermodynamic approach, equilibrium shape of domains was proposed (the simulation for tetragonal prism, tetragonal dipyramid, rombododecahedron, cubeoctahedron and their combination was made); possible variants of domain “cut” by concrete crystallographic planes were considered; simulation of structure disturbances on the interdomain boundaries was carried out; features of relative position and electric activity of mention above defects were analysed.
Annealing Effects of CuInS2 Single Crystals Grown by Traveling Heater Method
Authors: Yoshino Kenji , Nishimoto Masayuki , Shirakata Sho , Miyake Hideto , Hiramatsu Kazumasa , Yoneta Minoru , Ikari Tetsuo
Published: March 2014

Photoluminescence (PL) and piezoelectric photoacoustic (PPA) measurements are carried out at liquid nitrogen temperature for as-grown and vacuum annealed CuInS2 single crystals grown by a traveling heater method (THM). A new peak, due to S vacancy (VS) defect, is observed in the PPA spectrum after the vacuum annealing. A donor-acceptor pair (DAP) emission band which is due to a recombination between the V donor and In vacancy (VIn) acceptor appears while a DAP (VS donor and Cu vacancy (VCu) acceptor) emission band disappears in the PL spectrum after the vacuum annealing.
Thermal Analyses of CuInGeSe4 Quaternary Compound for Crystal Growth by Solution Method
Authors: Matsushita Hiroaki , Maeda Takashi , Katsui Akinori , Takizawa Takeo
Published: March 2014

In order to synthesize the single phase of quaternary compound CuInGeSe4 from the stoichiometric melt, the pseudo-binary phase diagram of the CuInSe2-GeSe2 system was investigated. The CuInGeSe4 phase was found to be formed through a peritectic reaction between CuInSe2 and liquid phase. We also constructed the phase diagrams of the pseudo-binary of the CuSe-CuInGeSe4, InSe-CuInGeSe4 and GeSe-CuInGeSe4 systems to find the solvents for firstly crystallizing CuInGeSe4 single phase. The results by the solution Bridgman method showed that CuSe is more suitable as a solvent to grow CuInGeSe4 single crystals.
Investigations of CVT Grown CuInS2 Single Crystals
Authors: Savchuk V. A.
Published: March 2014

CuInS2 single crystals were grown from initial components by using chemical vapour transport technique. Crystal composition and uniformity were controlled by EDAX and PL measurements. The EDAX data show an excess of sulfur atoms and the deficiency in copper and indium ones in grown by this method CuInS2 single crystals as compared with theoretical calculations for the ideal stoichiometric formula of the compound: Cu:In:S=25:25:50. Photoluminescence spectra present a series of complex transitions between energy states in the forbidden band. Free and bound exciton emissions have also been observed. PL results are discussed on the base of the model of nonmolecularity and nonstoichiometry and EDAX data.
Pressure Dependence of Energy Band Gap and Photoluminescence in AgxCu1-xGaS2 Single Crystals
Authors: Eom Sung-Hwan , Choi In-Hwan
Published: March 2014

Pressure dependence of energy band gaps and photoluminescence spectra in single crystals of Ag
x
Cu1x
GaS2 grown by the horizontal Bridgman and the iodine transport methods were investigated for the first time. The pressure coefficient of the band gap showed a quadratic increase with the Ag composition. Such quadratic variation is in contrast with that in CuInxGa1-x
Se2 single crystals. This phenomenon means that the bulk modulus and the volume deformation potential depend on the composition x. From the pressure coefficients of the photoluminescence (PL), the donor acceptor transition from the shallow donor to the deep acceptor show the same tendency as the pressure dependence of the energy band gaps with composition x. We suggest that the p-d hybridization in the valence band increases nonlinearly with the Cu composition.
A Direct Approach to Organic/Inorganic Semiconductor Hybrid Particles via Functionalized Polyfluorene Ligands
Authors: de Roo Tjaard , Haase Johannes , Keller Janine , Hinz Christopher , Schmid Marius , Seletskiy Denis V. , Cölfen Helmut , Leitenstorfer Alfred , Mecking Stefan
Published: February 2014

Controlled Suzuki–Miyaura coupling polymerization of 7′‐bromo‐9′,9′‐dioctyl‐fluoren‐2′‐yl‐4,4,5,5‐tetramethyl‐[1,3,2]dioxaborolane initiated by bromo(4‐tert‐butoxycarbonylamino‐phenyl)(tri‐tert‐butylphosphine)palladium (1) or bromo(4‐diethoxyphosphoryl‐phenyl)(tri‐tert‐butylphosphine)palladium (2) yields functionalized polyfluorenes (Mn = 4 × 103 g mol−1, Mw/Mn < 1.2) with a single amine or phosphonic acid, respectively, end‐group. High temperature synthesis of cadmium selenide quantum dots with these functionalized polyfluorenes as stabilizing ligands yields hybrid particles consisting of good quality (e.g. emission full width at half maximum of 30 nm; size distribution σ < 10%) inorganic nanocrystals with polyfluorene attached to the surface, as corroborated by transmission electron microscopy analysis and analytical ultracentrifugation. Sedimentation studies on particle dispersions show that a substantial portion (ca. half) of the phosphonic acid terminated polyfluorene ligands is bound to the inorganic nanocrystals, versus ca. 5% for the amino‐functionalized polyfluorene ligands. Single particle micro‐photoluminescence spectroscopy shows an efficient and complete energy transfer from the polyfluorene layer to the inorganic quantum dot.
Tailoring Crystallization: Towards High‐Performance Poly(lactic acid)
Authors: Liu Guoming , Zhang Xiuqin , Wang Dujin
Published: February 2014

Poly(lactic acid) (PLA) is one of the most promising alternatives for petrochemical‐based plastics. Crystallization mediation provides the simplest and most practical approach for enhancing the properties of PLA. Here, recent advances in understanding the relationship between crystalline structure and properties of PLA are summarized. Methods for manipulating crystallization towards high‐performance PLA materials are introduced.
Hydrophobic–hydrophilic polydivinylbenzene/polyacryldiethylenetriamine interpenetrating polymer networks and its adsorption performance toward salicylic acid from aqueous solutions
Authors: Wang Xiaomei , Liang Xiaolei , Huang Jianhan , Liu You‐Nian
Published: February 2014

Hydrophobic–hydrophilic interpenetrating polymer networks (IPNs) composed of polydivinylbenzene (PDVB) and polyacryldiethylenetriamine (PADETA) were prepared and its adsorption performance toward salicylic acid was studied from aqueous solutions. The structure of PDVB/PADETA IPNs was characterized by Fourier transform infrared spectroscopy, N2 adsorption–desorption isotherms, weak basic exchange capacity, and swelling ratio, respectively. The results indicated that PDVB/PADETA IPNs possessed both hydrophobic and hydrophilic properties and they were much superior to the hydrophobic PDVB and the hydrophilic PADETA in adsorption of salicylic acid from aqueous solutions. The Freundlich model was more appropriate for fitting the equilibrium data than the Langmuir model and the isosteric enthalpy decreased with increment of the equilibrium uptakes. The breakthrough dynamic capacity of salicylic acid on PDVB/PADETA IPNs was 77.27 mg/mL wet resin at an initial concentration of 650.4 mg/L and a flow rate of 7.2 BV/h (bed volume, 1 BV = 10 mL) and the saturated dynamic capacity was calculated to be 93.28 mg/mL wet resin. One hundred and forty milliliter of 0.01 mol/L of sodium hydroxide (w/v) and 40% of ethanol (v/v) could regenerate the resin column completely. © 2014 American Institute of Chemical Engineers AIChE J, 60: 2636–2643, 2014
Estimating striae of Retzius periodicity nondestructively using partial counts of perikymata
Authors: McFarlane Gina , Littleton Judith , Floyd Bruce
Published: February 2014

Accurate age estimations for enamel formation and the timing of enamel hypoplasia have traditionally only been available through histological analyses of dental thin sections, which is a difficult and destructive process. However, an association between striae of Retzius periodicity, crucial for accurate aging, and the total number of striae in imbricational enamel has been reported in the literature. This means periodicity can be estimated nondestructively but is reliant on all perikymata being visible along the crown surface. Therefore, crowns with worn or damaged surfaces may not be able to be assessed, potentially limiting sample sizes. We tested this relationship in a modern New Zealand sample and investigated whether reliable associations might be identified using only partial perikymata counts from the cervical half of the crown. Using mandibular canines (n = 11), the distribution of perikymata per decile was recorded using high definition replica surfaces. Thin sections of the same crowns were used to assess periodicity histologically along with striae of Retzius distributions. A strong correlation between total striae numbers and periodicity was also identified in our sample. Furthermore, we report strong correlations that allow periodicity to be estimated from perikymata counts using only 10% of crown height when certain deciles are used. Based on these findings, we propose a simple matrix that can be developed for nondestructively estimating periodicity based on the range of perikymata counts in the sixth to ninth deciles. Am J Phys Anthropol 154:251–258, 2014. © 2014 Wiley Periodicals, Inc.
Synthesis of 1‐silacyclopent‐2‐ene derivatives using 1,2‐hydroboration, 1,1‐organoboration and protodeborylation
Authors: Khan Ezzat , Tok Oleg L. , Wrackmeyer Bernd
Published: February 2014

The reaction of di(alkyn‐1‐yl)vinylsilanes R1(H2C═CH)Si(C≡C―R)2 (R1 = Me (1), Ph (2); R = Bu (a), Ph (b), Me2HSi (c)) at 25°C with 1 equiv. of 9‐borabicyclo[3.3.1]nonane (9‐BBN) affords 1‐silacyclopent‐2‐ene derivatives (3a, 3b, 3c, 4a, 4b), bearing one Si―C≡C―R function readily available for further transformations. These compounds are formed by consecutive 1,2‐hydroboration followed by intramolecular 1,1‐carboboration. Treated with a further equivalent of 9‐BBN in benzene they are converted at relatively high temperature (80–100°C) into 1‐alkenyl‐1‐silacyclopent‐2‐ene derivatives ( 5a, 5b 6a, 6b) as a result of 1,2‐hydroboration of the Si―C≡C―R function. Protodeborylation of the 9‐BBN‐substituted 1‐silacyclopent‐2‐ene derivatives 3, 4, 5, 6, using acetic acid in excess, proceeds smoothly to give the novel 1‐silacyclopent‐2‐ene (7, 8, 9, 10). The solution‐state structural assignment of all new compounds, i.e. di(alkyn‐1‐yl)vinylsilanes and 1‐silacyclopent‐2‐ene derivatives, was carried out using multinuclear magnetic resonance techniques (1H, 13C, 11B, 29Si NMR). The gas phase structures of some examples were calculated and optimized by density functional theory methods (B3LYP/6‐311+G/(d,p) level of theory), and 29Si NMR parameters were calculated (chemical shifts δ29Si and coupling constants nJ(29Si,13C)). Copyright © 2014 John Wiley & Sons, Ltd.
Coastal wetlands of Victoria, south‐eastern Australia: providing the inventory and condition information needed for their effective management and conservation
Authors: Boon Paul I. , Allen Tim , Carr Geoff , Frood Doug , Harty Chris , Mcmahon Andrew , Mathews Steve , Rosengren Neville , Sinclair Steve , White Matt , Yugovic Jeff
Published: February 2014

The effective management and conservation of coastal wetlands requires an appropriate typology to underpin classification and mapping, adequate inventory information, and a robust assessment of ecological condition and threats. Extensive and floristically diverse coastal wetlands occur along much of the coast of Victoria (south‐eastern Australia), but there are serious deficiencies in all these information requirements.

Previously unanalysed data from the Victorian Biodiversity Atlas were used to revise the typology currently applied to coastal saltmarsh in Victoria. To supplement the single unit currently used for State‐endorsed mapping and inventory (EVC 9 Coastal Saltmarsh Aggregate), seven new Ecological Vegetation Classes are proposed to better reflect the floristic and structural diversity of coastal saltmarsh in south‐eastern Australia. Coastal saltmarsh is currently allocated the lowest conservation status (‘least concern’) across much of Victoria, and it is recommended that this be upgraded variously to the higher categories of ‘endangered’, ‘vulnerable’, or ‘rare’.

A State‐wide inventory using the new typology, prepared using recently flown, high‐resolution aerial photographs and extensive ground‐truthing (212 person‐days), indicated that there were 19 212 ha of coastal saltmarsh of all types, 5177 ha of mangroves, and 3227 ha of EVC 10 Estuarine Wetland (a wetland type dominated byJuncus kraussii) in Victoria.

On‐ground assessments undertaken across 30 geographic sectors of the coast indicated that coastal wetlands were confronted by a wide range of anthropogenic threats, which in many cases were quite different from those outlined in prior reviews of Australian wetland systems. Weed invasions were especially problematic, not so much of the exotic and highly publicizedSpartinain the lower levels of tidal wetlands but from a wide range of exotic taxa in more elevated saltmarshes (e.g. tall wheat grassLophopyrum ponticum).

Copyright © 2014 John Wiley & Sons, Ltd.
On Prediction and Control of Discrete‐Time First‐Order Linear Stochastic Systems with Prospective Strong Intervention
Authors: Gai Rudong
Published: February 2014

This paper is devoted to studying the issue of modeling, forecasting, and optimal feedback control of discrete‐time first‐order linear stochastic systems with prospective strong intervention (PSI). First, one type of PSI is formulated. Then, one class of induced mechanisms of PSI is characterized, and, with respect to the induced mechanisms, two multi‐step forecasting methods for estimating the occurrence time and terminal time of PSI are discussed. Based on these fundamental results, the problem of optimal control with respect to an improved minimum variance performance index is discussed. Finally, the effectiveness and advantages of the proposed control strategy and approach are verified and demonstrated through numerical simulations.
Early life epigenetic programming and transmission of stress‐induced traits in mammals
Authors: Gapp Katharina , von Ziegler Lukas , Tweedie‐Cullen Ry Yves , Mansuy Isabelle M.
Published: February 2014

The environment can have a long‐lasting influence on an individual's physiology and behavior. While some environmental conditions can be beneficial and result in adaptive responses, others can lead to pathological behaviors. Many studies have demonstrated that changes induced by the environment are expressed not only by the individuals directly exposed, but also by the offspring sometimes across multiple generations. Epigenetic alterations have been proposed as underlying mechanisms for such transmissible effects. Here, we review the most relevant literature on these changes and the developmental stages they affect the most. We discuss current evidence for transgenerational effects of prenatal and postnatal factors on bodily functions and behavioral responses, and the potential epigenetic mechanisms involved. We also discuss the need for a careful evaluation of the evolutionary importance with respect to health and disease, and possible directions for future research in the field.
President's page
Authors: Bruce Harry
Published: February 2014

EDITOR'S SUMMARY

ASIS&T President Harry Bruce expresses joy and thanks for volunteers' contributions to the Association, pointing out advantages and challenges of a governance structure largely dependent on volunteer activity. Significant recent developments by volunteer committees include the Web Presence Task Force's recommendations for the ASIS&T website redesign, progressing to the RFP stage. The Membership Committee and International Relations Committee are working to strengthen and expand membership, attracting more global members and transitioning students to professional membership. Bruce envisions ASIS&T as the premier association for both information professionals and information scholars and points out the work of the Information Professionals Task Force to identify the many professional roles in the information industry. The Membership Committee will build on its work by encouraging current members to promote the value of membership for information professionals.
ASIS&T annual meeting award winners: Award of merit acceptance speech
Authors: Kuhlthau Carol Collier
Published: February 2014

EDITOR'S SUMMARY

As the recipient of ASIS&T's Award of Merit, Carol Collier Kuhlthau expressed appreciation for the association's influence on her scholarly development. Kuhlthau recounted the field's expansion and evolution from library school studies to information science, communication and social construction. Her focus on the information search process has been driven by questions about purpose in information seeking, user experience and affect. Her research into information seeking in learning has led pragmatically to Guided Inquiry, an educational design framework based on the scholar's research into the information search process. Highlighting information as central to people's everyday lives, Kuhlthau urged information scientists to focus on the practical implications of their work and how their research can be broadly applied to improve society.
Educating researchers for effective data management
Authors: Eaker Christopher
Published: February 2014

EDITOR'S SUMMARY

Attaining the goal of long‐term, open access to research data requires consistent data management, ideally by contributing scholars. Of several programs available to present data management instruction, three are described, compared and contrasted for use by graduate students. The collaborative product of six institutions, the New England Collaborative Data Management Curriculum includes an overview and six additional modules. Based on case studies, it features a flexible delivery method and timeframe. The DataONE Data Management Education Modules cover comparable topics in greater depth. Like the others, the University of Edinburgh's MANTRA is modular. It offers different perspectives based on roles and provides quizzes and additional resources. Each of the programs can be used for self‐paced training, adapted to a one‐day workshop or spread over a semester. Research institutions should consider customizing a program for their specific needs and researcher skills.
Complex patients treated with zotarolimus‐eluting resolute and everolimus‐eluting xience V stents in the randomized TWENTE trial: Comparison of 2‐year clinical outcome
Authors: Sen Hanim , Lam Ming Kai , Tandjung Kenneth , Löwik Marije M. , Stoel Martin G. , de Man Frits H.A.F. , Louwerenburg J. (Hans) W. , van Houwelingen Gert K. , Linssen Gerard C.M. , Doggen Carine J.M. , Basalus Mounir W.Z. , von Birgelen Clemens
Published: February 2014

Objective

To assess the differences in clinical outcome between complex patients treated with Resolute zotarolimus‐eluting stents (ZES) versus Xience V everolimus‐eluting stents (EES).

Background

Nowadays, many complex patients with coronary disease are treated with percutaneous coronary interventions, using drug‐eluting stents (DES).

Methods

We analyzed 2‐year outcome data of 1,033 complex patients of the TWENTE trial, treated with second‐generation Resolute ZES or Xience V EES. Complex patients had at least one of the following characteristics: renal insufficiency (creatinine ≥ 140 µmol/l); ejection fraction < 30%; acute myocardial infarction (MI) within previous 72 hrs; >1 lesion/vessel; >2 vessels treated; lesion length > 27 mm; bifurcation; saphenous vein graft lesion; arterial bypass graft lesion; in‐stent restenosis; unprotected left main lesion; lesion with thrombus; or lesion with total occlusion. Target vessel failure (TVF), the primary composite endpoint of the trial, was defined as cardiac death, target vessel‐related MI, or target vessel revascularization.

Results

Among the 1,033 complex patients, 529 (51%) were treated with Resolute ZES and 504 (49%) with Xience V EES. Patient‐ and procedure‐related characteristics were similar between DES groups. After 2‐year follow‐up, outcome was also similar between DES groups. TVF occurred in 12.1% of patients treated with Resolute ZES and 12.3% of patients treated with Xience V EES. In addition, DES groups did not differ significantly in cardiac death, MI, or target vessel revascularization—the individual components of TVF.

Conclusion

Complex patients treated with Resolute ZES and Xience V EES showed similar safety and efficacy during 2‐year follow‐up. © 2014 Wiley Periodicals, Inc.
Safety and long‐term outcomes after percutaneous coronary intervention in patients with human immunodeficiency virus
Authors: Badr Salem , Minha Sa'ar , Kitabata Hironori , Fatemi Omid , Torguson Rebecca , Suddath William O. , Satler Lowell F. , Pichard Augusto D. , Waksman Ron
Published: February 2014

Objective

This study aims to report the long‐term outcomes after percutaneous coronary intervention (PCI) in human immunodeficiency virus (HIV+) patients.

Background

Sparse data exists regarding the risk of patients with HIV who undergo PCI.

Methods

Using a case‐control design, we compared baseline characteristics, procedure‐related outcomes, in‐hospital, and 2‐year clinical outcomes of 112 consecutive HIV+ patients versus 112 HIV‐ controls matched for age, gender, and diabetes mellitus who underwent PCI from April 2003 to September 2011.

Results

Baseline characteristics were generally comparable, save for more African Americans and history of chronic renal insufficiency in the HIV+ vs. HIV‐ group (62.5% vs. 21.4%, P < 0.001) and (27.7% vs. 9.9%, P < 0.001). There was no correlation between CD4 nadir count and extent and diffuseness of coronary artery disease. The occurrence of major adverse cardiac events at 2 years was similar in both groups. Multivariable analysis for independent correlates of major adverse cardiac events at 2 years detected patients with a history of chronic renal insufficiency (OR: 2.44, 95% confidence interval: 1.02–5.83; P = 0.04) and acute myocardial infarction (OR: 2.92, 95% confidence interval: 1.39–6.15; P = 0.005) as correlates for outcome. Post‐hoc analysis showed that drug‐eluting stent (DES) use in the HIV+ group was beneficial.

Conclusion

PCI in HIV+ patients is safe, with high procedural success rates, and produces similar outcomes to those seen in HIV‐ patients at 2 years. HIV+ patients should be treated with DES if possible. © 2014 Wiley Periodicals, Inc.
Standardizing radiation dose reporting in the pediatric cardiac catheterization laboratory—A multicenter study by the CCISC (Congenital Cardiovascular Interventional Study Consortium)
Authors: Kobayashi Daisuke , Meadows Jeffery , Forbes Thomas J. , Moore Phillip , Javois Alexander J. , Pedra Carlos A. , Du Wei , Gruenstein Daniel H. , Wax David F. , Hill James A. , Graziano Joseph N. , Fagan Thomas E. , Alvarez Walter Mosquera , Nykanen David G. , Divekar Abhay A.
Published: February 2014

Objectives

We examine normalized air Kerma area product (PKA) by body weight (PKA/BW) as a reference value of radiation dose and benchmark PKA/BW in pediatric laboratories using a multicenter registry database.

Background

Reduction of radiation dose is an important quality improvement task in pediatric cardiac catheterization laboratories. Physicians need to agree on a standard method of reporting radiation dose that would allow comparisons to be made between operators and institutions.

Methods

This was a multicenter observational study of radiation dose in pediatric laboratories. Patient demographic, procedural and radiation data including fluoroscopic time and PKA (µGy m2) were analyzed. PKA/BW was obtained by indexing PKA to body weight.

Results

A total of 8,267 pediatric catheterization procedures (age <18 years) were included from 16 institutions. The procedures consisted of diagnostic (n = 2,827), transplant right ventricular (RV) biopsy (n = 1,172), and interventional catheterizations (n = 4268). PKA correlated with body weight better than with age and best correlated with weight–fluoroscopic time product. PKA/BW showed consistent values across pediatric ages. Interventional catheterizations had the highest PKA/BW (50th, 75th, and 90th percentiles: 72, 151, and 281 μGy m2/kg), followed by diagnostic (59, 105, and 175 μGy m2/kg) and transplant RV biopsy (27, 79, and 114 μGy m2/kg).

Conclusion

PKA/BW appeared to be the most reliable standard to report radiation dose across all procedure types and patient age. We recommend PKA/BW to be used as the standard unit in documenting radiation usage in pediatric laboratories and can be used to evaluate strategies to lower radiation dosage in pediatric patients undergoing cardiac catheterizations. © 2014 Wiley Periodicals, Inc.
Significance of the diagnostic categories “atypical” and “suspicious for malignancy” in the cytologic diagnosis of solid pancreatic masses
Authors: Layfield Lester J. , Schmidt Robert L. , Hirschowitz Sharon L. , Olson Matthew T. , Ali Syed Z. , Dodd Leslie L.
Published: February 2014

Endoscopic ultrasound guided (EUS) fine‐needle aspiration (FNA) investigation of solid pancreatic lesions has been shown to have good sensitivity and specificity. Many lesions can be definitely classified as benign or malignant but some can only be cytologically classified as “atypical” or “suspicious for malignancy”. Risk for malignancy in these indeterminate categories has not been well categorized. The cytology records of four University Medical centers were searched for all EUS guided FNAs of solid pancreatic lesions. All cases with a diagnosis of “atypical”, or “suspicious for malignancy” were selected for analysis when histologic biopsy or over 18 months clinical follow‐up was available. Two hundred and ninety‐two cases with a diagnosis of “atypical” or “suspicious for malignancy” and adequate follow‐up were obtained from the combined data of the four institutions. The percentage malignant for the categories “atypical” and “suspicious for malignancy” were 79.2 and 96.3%, respectively. If the category “atypical” was classified as benign and “suspicious for malignancy” was classified as malignant, the resulting positive predictive value was 96.3 (95% CI: 92.6–98.5) and the negative predictive value 20.8 (95% CI: 13.4–30.0). The categories of “atypical” and “suspicious for malignancy” stratify risk for malignancy in a fashion, which may aid in patient counseling and selection of follow‐up protocols. Classification of “suspicious for malignancy” as malignant optimizes diagnostic sensitivity and specificity. Diagn. Cytopathol. 2014;42:292–296. © 2014 Wiley Periodicals, Inc.
MMP‐9 expression increases according to the grade of squamous intraepithelial lesion in cervical smears
Authors: Matheus Erika R. , Zonta Marco A. , Discacciati Michelle G. , Paruci Priscila , Velame Fernanda , Cardeal Laura B.S. , Barros Silvia B.M. , Pignatari Antonio C. , Maria‐Engler Silvya S.
Published: February 2014

Studies about cervical carcinogenesis have demonstrated the increased expression of matrix‐metalloproteinase (MMP) according to the grade of cervical intraepithelial lesions. Considering the importance of innovative techniques to introduce noninvasive and rapid diagnoses for patients, this study aimed to perform MMP‐9 immunocytochemistry in cervical smears according to the cytopathological diagnoses, in order to monitor MMP activity in cervical smears. This cross‐sectional study investigated the expression of MMP‐9 in normal cervical smears, inflammatory cervical smears, squamous intraepithelial lesions, and cervical carcinoma. Cervical smears from 630 women were collected for cytopathological diagnoses and immunocytochemistry. Women with squamous intraepithelial lesions showed an increase in MMP‐9 expression, with moderate to intense staining occurring with increasing cervical lesion grade. The prevalence of moderate to intense MMP‐9 staining was 9% in normal cervical smears, 12% in cervical inflammation, 24% in low‐grade squamous intraepithelial lesion (LSIL), 92% in high‐grade squamous intraepithelial lesions (HSIL) and 100% in cervical carcinoma cases. In the specific case of LSIL, we found that association with MMP‐9 is more evident when there is the simultaneous presence of an infectious agent. Thus, the expression of MMP‐9 in cervical smears increases according to the grade of cervical lesion and LSIL in the presence of infectious agents showed higher MMP‐9 expression than women with LSIL without infectious agents. Diagn. Cytopathol. 2014;42:827–833. © 2014 Wiley Periodicals, Inc.
Modeling the role of the close‐range effect and environmental variables in the occurrence and spread of Phragmites australis in four sites on the Finnish coast of the Gulf of Finland and the Archipelago Sea
Authors: Altartouri Anas , Nurminen Leena , Jolma Ari
Published: February 2014

Phragmites australis, a native helophyte in coastal areas of the Baltic Sea, has significantly spread on the Finnish coast in the last decades raising ecological questions and social interest and concern due to the important role it plays in the ecosystem dynamics of shallow coastal areas. Despite its important implications on the planning and management of the area, predictive modeling of Phragmites distribution is not well studied. We examined the prevalence and progression of Phragmites in four sites along the Southern Finnish coast in multiple time frames in relation to a number of predictors. We also analyzed patterns of neighborhood effect on the expansion and disappearance of Phragmites in a cellular data model. We developed boosted regression trees models to predict Phragmites occurrences and produce maps of habitat suitability. Various Phragmites spread figures were observed in different areas and time periods, with a minimum annual expansion rate of 1% and a maximum of 8%. The water depth, shore openness, and proximity to river mouths were found influential in Phragmites distribution. The neighborhood configuration partially explained the dynamics of Phragmites colonies. The boosted regression trees method was successfully used to interpolate and extrapolate Phragmites distributions in the study sites highlighting its potential for assessing habitat suitability for Phragmites along the Finnish coast. Our findings are useful for a number of applications. With variables easily available, delineation of areas susceptible for Phragmites colonization allows early management plans to be made. Given the influence of reed beds on the littoral species and ecosystem, these results can be useful for the ecological studies of coastal areas. We provide estimates of habitat suitability and quantification of Phragmites expansion in a form suitable for dynamic modeling, which would be useful for predicting future Phragmites distribution under different scenarios of land cover change and Phragmites spatial configuration.
Sensitivity of salmonella YG5161 for detecting PAH‐associated mutagenicity in air particulate matter
Authors: Umbuzeiro Gisela A. , Kummrow Fábio , Morales Daniel Alexandre , Alves Debora Kristina M. , Lim Hwanmi , Jarvis Ian W.H. , Bergvall Christoffer , Westerholm Roger , Stenius Ulla , Dreij Kristian
Published: February 2014

The Salmonella/microsome assay is the most used assay for the evaluation of air particulate matter (PM) mutagenicity and a positive correlation between strain TA98 responses and benzo[a]pyrene (B[a]P) levels in PM has been found. However, it seems that the major causes of PM mutagenicity in this assay are the nitro and oxy‐PAHs. Salmonella YG5161, a 30‐times more responsive strain to B[a]P has been developed. To verify if YG5161 strain was sufficiently sensitive to detect mutagenicity associated with B[a]P mutagenicity, PM samples were collected in Brazil and Sweden, extracted with toluene and tested in the Salmonella/microsome microsuspension assay. PAHs and B[a]P were determined and the extracts were tested with YG5161 and its parental strain TA1538. The extracts were also tested with YG1041 and its parental strain TA98. For sensitivity comparisons, we tested B[a]P and 1‐nitropyrene (1‐NP) using the same conditions. The minimal effective dose of B[a]P was 155 ng/plate for TA1538 and 7 ng/plate for YG5161. Although the maximum tested dose, 10 m3/plate containing 9 ng of B[a]P in the case of Brazilian sample, was sufficient to elicit a response in YG5161, mutagenicity was detected at a dose as low as 1 m3/plate (0.9 ng). This is probably caused by nitro‐compounds that have been shown to be even more potent than B[a]P for YG5161. It seems that the mutagenicity of B[a]P present in PM is not detectable even with the use of YG5161 unless more efficient separation to remove the nitro‐compounds from the PAH extract is performed. Environ. Mol. Mutagen. 55:510–517, 2014. © 2014 Wiley Periodicals, Inc.