bluuebunny/crossref_metadata_2025_split huggingface dataset:
Hyperfine structure associated with the dominant radiation‐induced trapped hole center in RbTiOPO4 crystals
Authors: Jiang Yongquan , Halliburton L. E. , Roth M. , Tseitlin M. , Angert N. 
Published: August 2005

AbstractElectron paramagnetic resonance (EPR) and electron‐nuclear double resonance (ENDOR) have been used to characterize the complex hyperfine patterns exhibited by the primary radiation‐induced trapped hole center in single crystals of RbTiOPO4 (commonly referred to as RTP). These defects are produced at 77 K by irradiating with X‐rays, and they are destroyed by raising the temperature above approximately 170 K. In this center, the hole resides on a bridging oxygen ion located between two titanium ions and is stabilized by a nearby rubidium vacancy. Hyperfine splittings from interactions with one rubidium neighbor and one phosphorus neighbor are resolved in the EPR spectra. The ENDOR spectra show one larger phosphorus interaction and four smaller phosphorus interactions. Principal values and principal axis directions for this larger phosphorus interaction are obtained from the ENDOR angular dependence. (© 2005 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Structural property and half‐metallicity for 3d transition metals on GaAs surface
Authors: Kang Byung‐Sub , Chung Jean‐Soo , Kang Hee‐Jae , Oh Suhk‐Kun 
Published: August 2005

AbstractThe structural and magnetic properties of the surface and interface are studied for the hypothetical zinc‐blende phase of 1–2 monolayers (MLs) M (= Cr, Mn, Fe, or Co) on GaAs(001) or AsGa(001) by first‐principles calculations. We present the energetics for the systems of mixed M(Ga,As) and of a M overlayer on the substrate in order to obtain a systematic understanding of interfacial mixing. A heterointerfacial mixing of M(Ga,As) on GaAs(001) or AsGa(001), which consists of a tetrahedrally coordinated M atom of an empty site, is energetically favorable. The mixed M(Ga,As) (hypothetical zinc‐blende) with 1–2 ML M on GaAs(001) is more energetically stable than the zinc‐blende M(Ga,As). A surface Cr atom on an As‐terminated substrate retains the half‐metallicity in the case of 1–2 ML M with a zinc‐blende lattice, while it disappears for the surface Cr atom of the Ga termination. (© 2005 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Spectroscopic studies of 2H‐PbI2(Mn) layered crystals
Authors: Motsnyi F. V. , Dorogan V. G. , Kovalyuk Z. D. , Okulov S. M. , Yaremko A. M. 
Published: August 2005

AbstractFor the first time we studied Raman, exciton and EPR spectra of PbI2 layered crystals of 2H polytype doped with high concentration of Mn impurity. A novel type of Fermi resonance was found. The anomalous temperature shift of the exciton band n = 1 was registered. It was shown that this shift can be explained by means of anharmonic vibrations of layered lattice at T < 40 K and low‐frequency optical phonons at T > 40 K. The manifestation of single and exchange‐bound Mn2+ ions in EPR spectra was observed. (© 2005 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Field electron energy spectroscopy of alumina‐supported platinum adatoms
Authors: Cörper A. , Bozdech G. , Ernst N. , Klüner T. , Freund H.‐J. 
Published: August 2005

AbstractField electron energy spectroscopy and density functional calculations have been employed to characterize electronic properties of single Pt‐adatoms deposited on a thin alumina film. For Pt/Al2O3/NiAl(110) strong current enhancements were measured about 1.4 eV below the Fermi energy. No features were observed for clean Al2O3/NiAl(110) and Pt/NiAl(110) in the accessible energy range. As an explanation we propose a resonance tunneling mechanism involving an occupied electronic state of the Pt adatom close to the Fermi level. (© 2005 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Intersubband transitions in coupled triple‐graded quantum wells under an electric field
Authors: Kasapoglu E. , Sari H. , Sokmen I. 
Published: August 2005

AbstractThe intersubband transitions were calculated in three different shaped triple‐graded quantum wells. The investigation involved changing the depth of the central well potential under an electric field applied parallel to the growth direction. By changing the depth of the central well potential, one can tune the resonance photon energy. This tunability gives a possibility for the realization of near‐infrared electro‐absorption modulators and detectors. In addition, the absorption coefficient as a function of the incident photon energy was obtained for the 1–2 transition in a triple square quantum well structure having the same physical parameters as the triple‐graded quantum well structure. (© 2005 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Transmission properties of light through the Family B of generalized Thue–Morse multilayers
Authors: Chen Fuming , Yang Xiangbo 
Published: August 2005

AbstractIn this paper, we study the transmission properties of light through the Family B of Generalized Thue–Morse (FBGTM(m)) aperiodic multilayers and find that for the normal incidence of light there exist three kinds of cases for propagation matrices and corresponding transmission coefficients: (1) when m is even, the former are two‐circular and the latter are constant; (2) when m = 1, the former and the latter are all constant; (3) when m is odd but does not equal to 1, the former are all diagonal except 1st‐generation system. The two non‐zero elements are count‐downs for each other and decrease or increase rapidly with the increase of both the generation number l and the parameter m. The latter are constant when l ≤ 2 and tend to be zero when l ≥ 3. The analytic results are confirmed by numerical simulations. (© 2005 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
One‐dimensional XY antiferromagnetic Heisenberg model with nearest and next nearest neighbour exchange interactions
Authors: Gouvêa M. E. , Pires A. S. T. 
Published: August 2005

AbstractWe study the one‐dimensional anisotropic antiferromagnetic Heisenberg model with competing interactions using the self‐consistent harmonic approximation. The dispersion relation, the correlation function and the susceptibility are obtained for several values of the ratio δ = J2/J1 between the nearest (J1) and next nearest neighbour exchange interactions (J2). For δ < 0.25, the pair correlation function decays monotonically and exponentially to zero and the susceptibility has a maximum value at q = π. For J2 > 0.25J1, the exponential decay of the pair correlation is modified by an oscillatory behavior while the maximum of the susceptibility does not necessarily occur at q = π. Furthermore, the phase diagram of a system with weakly coupled chains is considered. (© 2005 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Thermally induced carbon–oxygen complexes in GaAs
Authors: Ulrici W. , Jurisch M. 
Published: August 2005

AbstractIn LEC‐grown oxygen‐containing GaAs, a vibrational absorption line is observed at 2059.6 cm–1 for T = 7 K after long‐time annealing at (700 ± 100) °C. This line is due to the stretching mode of a 12C–16O complex, since the line due to the isotopically shifted 13C–16O mode is observed at 2003.8 cm–1. Several other 12C–16O stretching modes found in this frequency region are assigned to C–O complexes with different environments. The formation of C–O complexes around 700 °C becomes possible as a result of the mobility of oxygen atoms. After the same annealing procedure, two vibrational lines are measured at 1828.2 and 1891.4 cm–1 for T = 7 K and assigned to the stretching modes of an 11B–16O (10B–16O) complex. (© 2005 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Pressure dependence of the melting temperature of aluminum
Authors: Zou Yong , Chen Li‐rong 
Published: August 2005

AbstractOn the basis of Lindemann's law, the Debye model, and the assumption that the quantity αBT is constant above the Debye temperature, the melting temperature of aluminum was calculated for a wide range of pressure with the help of the P–V–T relationships based on the Chopelas–Boehler approximation. The calculated results of the melting temperature versus pressure are in good agreement with experimental values. (© 2005 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Electronic band structure of high‐index silicon nanowires
Authors: Scheel H. , Reich S. , Thomsen C. 
Published: August 2005

AbstractWe calculated the electronic properties of high‐index free‐standing silicon nanowires. [11$ \bar 2 $] nanowires are indirect semiconductors for diameters down to 0.8 nm; [110] wires have a direct band gap at the Γ‐point, but the density of states is very small at the conduction band edge. Confinement arguments show that only [001] nanowires are expected to develop a direct gap with a large density of electronic states at the band edges for diameters in the nm range. The magnitude of the gap depends strongly on the wire growth direction, which is due to the different effective confinement length and effective masses for the Γ X‐derived silicon states. Correcting for the extension of the wave functions we find our calculated energies to agree with recent scanning tunneling experiments. (© 2005 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
An isoform shift in the cardiac adenine nucleotide translocase expression alters the kinetic properties of the carrier in dilated cardiomyopathy
Authors: Dörner Andrea , Giessen Stefanie , Gaub Regina , Siestrup Helga Große , Schwimmbeck Peter L. , Hetzer Roland , Poller Wolfgang , Schultheiss Heinz‐Peter 
Published: August 2005

AbstractBackground:Impaired mitochondrial ADP/ATP transport and altered adenine nucleotide translocase (ANT) isoform expression characterized by enhanced ANT1 and decreased ANT2 expression have been implicated in the pathophysiology of dilated cardiomyopathy (DCM). It is still unknown whether restricted ANT function results from exogenous factors, or mutations in the ANT genes, or whether the imbalance in the isoform composition causes the reduced ADP/ATP transport. We performed DNA mutation screening of ANT genes and analyzed the kinetic properties of ANT protein isolated from DCM hearts and controls in a reconstituted system excluding natural environmental influences.Results:A G1409T polymorphism in ANT2 leads to an exchange from Arg111 to Leu111 in healthy blood donors (n=60) with allele frequencies of 76% and 24%. This polymorphism was neither associated with DCM (74%, 26%; n=93) nor with altered myocardial ANT isoform expression or restricted ANT function (89%, 11%; n=8). However, there was a remarkable reduction in the maximum transport activity (vmax) of reconstituted ANT from DCM hearts with altered ANT isoform expression (498±113 μmol min−1 g−1 incorporated protein vs. 1112±178 μmol min−1 g−1 incorporated protein, p<0.01). Moreover, the substrate affinity of DCM myocardial ANT to ATP was slightly reduced with an increased Km value of 104.3±2.4 μM vs. 90.4±2.9 μM in controls (p<0.03).Conclusion:The altered isoform expression in DCM hearts entails changes in the kinetic properties of total ANT protein restricting ANT function and contributing to disturbed energy metabolism in DCM.
Outcome in patients with an ICD incorporating cardiac resynchronisation therapy: Differences between primary and secondary prophylaxis
Authors: Theuns Dominic A.M.J. , Thornton Andrew S. , Klootwijk A. Peter J. , Scholten Marcoen F. , Vantrimpont Pascal J.M.J. , Balk Aggie H.M.M. , Jordaens Luc J. 
Published: August 2005

AbstractBackground:The incidence of ventricular tachyarrhythmias in ICD patients with cardiac resynchronisation therapy (CRT‐D) is not well studied.Aim:To analyse event free survival in CRT‐D patients with a primary or a secondary prophylactic ICD indication.Methods:Prospective, single centre. Eighty‐six patients, 44% with a primary prophylactic indication. Actuarial event‐free rates for mortality and arrhythmias were calculated.Results:Baseline clinical characteristics were not significantly different between primary and secondary prophylaxis. Primary prophylaxis patients were more likely to be in NYHA class III. Over 21 months, 724 ventricular events with therapy occurred in 36 patients (42%). The actuarial event‐free rates, at 1 and 3 years, from appropriate ICD therapy were higher (P<0.001) for primary (79.0% and 67.8%) than for secondary prophylaxis (45.6% and 27.0%). Appropriate ICD therapy occurred more in NYHA class II compared to class III (P=0.016). Underlying disease (ischemic versus non‐ischemic) and functional class did not play a role in multivariate analysis.Conclusion:Important arrhythmic events in patients with heart failure, and CRT‐D occur at a very high rate when the indication is secondary prophylaxis. Patients with primary prophylaxis have an annual event rate of 10%, even though they tend to have a worse heart failure class.
The disappearing art of instrumental delivery: Time to reverse the trend
Authors: Bailey P.E. 
Published: August 2005

AbstractPurpose: This paper focuses attention on declining rates of instrumental (vacuum or forceps) delivery. The decline often means that women must travel further to deliver in hospitals with capacity for cesarean delivery. Background: The paper illustrates recent trends in the use of vacuum extraction and forceps in low‐ and high‐income countries. It describes some of the obstacles to the use of instrumental delivery and why the techniques, especially vacuum extraction, should be reintroduced. Over the past two decades, many countries have observed a decline in instrumental delivery rates while cesarean rates have increased. Objections to instrumental delivery are largely due to the potential harm it causes newborns. Some medical schools no longer train their professionals to perform instrumental delivery. Elsewhere, only specialists are permitted to perform the procedures. Methods and Results: As this is a policy paper rather than a research report, the methods and results sections are not applicable. Conclusions: Vacuum extraction can be taught to midlevel practitioners (midwives, nurse practitioners and general physicians), thereby increasing access to emergency obstetric care especially at the periphery. This allows women to give birth closer to home in midlevel facilities when hospitals are not easily accessible or are overcrowded. Where instrumental and cesarean delivery are both available, instrumental delivery could potentially reduce the risks associated with cesarean delivery and reduce the costs of obstetric care.
Fractalkine in the peritoneal fluid of women with endometriosis
Authors: Shimoya K. , Zhang Q. , Temma‐Asano K. , Hayashi S. , Kimura T. , Murata Y. 
Published: August 2005

AbstractObjective: The objective of this study was to evaluate the presence of fractalkine in the ascites and the association between fractalkine levels in the ascites and endometriosis. Methods: Peritoneal fluids and peripheral blood samples were obtained from patients undergoing laparoscopy for infertility work‐up or laparoscopic cystectomy. Three samples of peritoneum were obtained from patients undergoing hysterectomy. Western blotting, RT‐PCR and immunohistochemistry were performed. Results: Fractalkine protein was detected in the ascites. Positive staining was confirmed in peritoneal surface cells and perivascular cells of the peritoneum. CX3CR1 positive cells were present in the cells in the peritoneal fluid. The fractalkine concentrations in the ascites of patients with endometriosis were lower than those without endometriosis. There was no significant difference between serum fractalkine levels in patients with and without endometriosis. Conclusion: The decreased level of fractalkine found in the peritoneal fluid of patients with endometriosis may contribute to the pathogenesis of endometriosis.
Oral, vaginal and sublingual misoprostol for induction of labor
Authors: Bartusevicius A. , Barcaite E. , Nadisauskiene R. 
Published: August 2005

AbstractObjective: To evaluate the effectiveness and safety of different administration routes of misoprostol for induction of labor.Method: PubMed, Cochrane Library and EMBASE searches were carried out using the keywords oral, vaginal, sublingual, buccal, misoprostol, labor induction, identifying randomized case–controlled trials comparing different routes for giving misoprostol to induce labor, published in English between 1994 and 2004. Results: Seventeen studies (3549 participants) were included. Compared to vaginal administration, oral misoprostol was associated with higher failure rates for achieving vaginal delivery within 24 h (odds ratio (OR) 1.61, 95% confidence interval (CI) 1.23–2.10), higher rates of uterine hyperstimulation without fetal heart rate (FHR) changes (OR 2.21, 95% CI 1.12 – 4.34) and lower cesarean section rates (OR 0.74, 95% CI 0.56–0.97). A lower dose of oral misoprostol (50 μg) compared to the 25–50 μg administered vaginally was associated with a higher rate of vaginal delivery not being achieved within 24 h (OR 3.60, 95% CI 2.10 – 6.18), more need for oxytocin augmentation (OR 2.19, 95% CI 1.65–2.92), less uterine hyperstimulation both without FHR changes (OR 0.58, 95% CI 0.42–0.80) and with FHR changes (OR 0.34, 95% CI 0.17–0.67) and fewer cesarean sections (OR 0.69, 95% CI 0.51–0.91). Compared to vaginal administration, buccal misoprostol resulted in a higher rate of failure to achieve vaginal delivery after 24 h, more frequent uterine hyperstimulation and lower rates of cesarean section, but these differences were not significant. When 50 μg of misoprostol used sublingually was compared to oral administration, the sublingual misoprostol was associated with less failure to achieve vaginal delivery after 24 h, less oxytocin augmentation and reduced cesarean section, but none of the differences were statistically significant. Conclusions: Vaginal misoprostol appears more effective than the equivalent dosage administered orally. However, the vaginal route appears to be associated with a higher risk of uterine hyperstimulation. Sublingual misoprostol seems an effective route of administration, but a lack of data necessitates more clinical trials to establish the effectiveness and safety of the buccal/sublingual route.
Three-dimensional transition in the wake of bluff elongated cylinders
Authors: RYAN K. , THOMPSON M. C. , HOURIGAN K. 
Published: August 2005

Despite little supporting evidence, there appears to be an implicit assumption that the wakes of two-dimensional bluff bodies undergo transition to three-dimensional flow and eventually turbulence, through the same sequence of transitions as observed for a circular cylinder wake. Previous studies of a square cylinder wake support this assumption. In this paper, the transition to three-dimensional wake flow is examined for an elongated cylinder with an aerodynamic leading edge and square trailing edge. The three-dimensional instability modes are determined as a function of aspect ratio ($\hbox{\it AR}\,{=}\,$length to width). Floquet analysis reveals that three distinct instabilities occur. These are referred to as Modes A, B$^\prime$ and S$^\prime$ through analogy with the modes for circular and square cylinders. For aspect ratios less than approximately 7.5, Mode A is the most unstable mode. For aspect ratios greater than this, the most unstable mode switches to Mode B$^\prime$. This has the same spatio-temporal symmetry as Mode B for a circular cylinder, but a spanwise wavelength and near-wake features more in common with Mode S for a square cylinder. The dominant wavelength for this mode is approximately two cylinder thicknesses, much longer than for Mode B for a circular cylinder. It is found that the critical Reynolds number for the onset of the Mode A instability varies approximately with the square root of the aspect ratio. On the other hand, the critical Reynolds number for Mode B$^\prime$ is almost independent of aspect ratio. For large aspect ratios, the separation in Reynolds number between the critical Reynolds numbers is substantial; for instance, for $\hbox{\it AR}\,{=}\,17.5$, these values are approximately 450 and 700. In fact, for this aspect ratio, the third instability mode, Mode S$^\prime$, is more unstable than Mode A. These results suggest that the transition scenario for elongated bluff bodies may be distinctly different to short bodies such as circular or square cylinders. At the very least, the dominant spanwise wavelength in the turbulent wake is likely to be much longer than that for a circular cylinder wake. In addition, the reversal of the ordering of occurrence of the two modes with the different spatial symmetries is likely to affect the development of spatio-temporal chaos as a precursor to fully turbulent flow.In conjunction with prior work, the current results indicate that nearly all three-dimensional instabilities of the vortex street can be identified as one of only a handful of transition modes.
Effects of an opening on pressure wave propagation in a tube
Authors: AUVITY B. , BELLENOUE M. 
Published: August 2005

This paper focuses on the effects of an opening placed along a tube on the propagation of a pressure wavefront. Such a configuration has been chosen for its relevance to many of the countermeasures envisaged in reducing strong pressure transients in tunnels due to the entry of high-speed trains (this installation includes a perforated entrance hood and ventilation shaft). We will start by establishing that when a compression wavefront passes through an opening, the front is split into an infinite number of smaller pressure steps, with their amplitude expressed as the terms of a mathematical series. The main parameter of the series is a transmission coefficient of the opening. The shape of each of the smaller pressure steps is driven by the transmission–reflection process that takes place at the opening. Both experimental and numerical studies have been carried out to carefully estimate both the transmission coefficient and the shape of the transmitted and reflected pressure waves. Three major parameters are identified: the relative surface area of the opening to the tube cross-section, the ratio of the incident front length to the longitudinal opening length, and the incident front amplitude.It will be shown that the transmission coefficient decreases exponentially with the relative surface area of the opening and is significantly influenced by the incident front amplitude. Both the length and shape of the transmitted front are similar to those of the incident front. The reflected front length, however, increases linearly with the incident front length as well as with the longitudinal opening length. The shape of the reflected front is greatly influenced by the incident front length. A linear analysis has been conducted and shows that the transmission coefficient can be predicted in a straightforward manner. These results are deemed to be of help not only in the design of countermeasures for the train/tunnel entry problem, but also for technological applications involving transient pressure pulses in branched pipe flows (e.g. pulsed flow in exhaust pipes).
Bounds for the index of the centre in capable groups
Authors: Podoski K. , Szegedy B. 
Published: August 2005

A group

H
H

is called capable if it is isomorphic to

G

/

Z

G/\mathbb {Z}

for some group

G
G

. Let

H
H

be a capable group. I. M. Isaacs (2001) showed that if

H
H

is finite, then the index of the centre is bounded above by some function of

|

H
′

|

|H’|

. We show that if

|

H
′

|

>
∞

|H’|>\infty

, then

|

H
:
Z
(
H
)

|

≤

|

H
′

|

c

log
2

⁡

|

H
′

|

|H:Z(H)|\leq |H’|^{c\log _2|H’|}

with some constant

c
c

and this bound is essentially best possible. We complete a result of Isaacs, showing that if

H
′

H’

is a cyclic group, then

|

H
:

Z

(
H
)

|

≤

|

H
′

|

2

|H:\mathbf {Z}(H)|\leq |H’|^2

.