bluuebunny/crossref_metadata_2025 huggingface dataset:
Heterodyne single‐beam CARS microscopy
Authors: Müller Christina , Buckup Tiago , von Vacano Bernhard , Motzkus Marcus
Published: April 2009

In single‐beam coherent anti‐Stokes Raman spectroscopy (CARS), a complete four‐wave‐mixing scheme is accomplished within a single pulse from an ultrashort femtosecond oscillator. Spectral information is achieved by coherent control of the non‐linear signal generation using phase modulation of the excitation with a pulse shaper. This single‐beam approach can be even extended to heterodyne detections schemes wherein a strong local oscillator (LO) field, also generated by pulse shaping from the same excitation laser, interferes with the CARS signal. Here, we explore the potential of this promising technique. A careful optimisation of the experimental scheme is presented together with an analysis of the different relations between LO field and CARS signal intensity, discovering an optimal LO field at a fraction of about 10−4 compared to the overall CARS excitation energy. With the optimised set‐up, an absolute number of molecules as low as 5 × 106 corresponding to concentrations in the attomole regime in the focal volume can be detected. Using such an optimal parameterisation, heterodyne single‐beam CARS based on a broadband laser source is introduced to microscopic applications, combining chemical selectivity and a high spatial resolution of the non‐linear CARS process with the sensitivity of the heterodyne approach. Copyright © 2009 John Wiley & Sons, Ltd.
Polarization Raman study of protein ordering by controllable RBC deformation
Authors: Rao Satish , Bálint Štefan , del Carmen Frias Luisa , Petrov Dmitri
Published: April 2009

Polarized Raman spectroscopy is used to provide evidence of hemoglobin protein ordering as the red blood cell (RBC) is stretched with optical tweezers. The stretching of the cell is intended to mimic the deformation that it experiences as it travels through vessels and capillaries. The depolarization ratios for a number of heme Raman bands change as the cell is stretched, confirming the semi‐ordered nature of the hemoglobin ensemble in the cytoplasm. Furthermore, trends observed in the ratio shifts point to increased packing and ordering of the Hb after cell stretching. This evidence should shed more light on to the role of deformation in the RBC function. Copyright © 2009 John Wiley & Sons, Ltd.
FT‐IR and FT‐Raman spectra and ab initio calculations of 3‐{[(2‐hydroxyphenyl) methylene]amino}‐2‐phenylquinazolin‐4(3H)‐one
Authors: Yohannan Panicker C. , Varghese Hema Tresa , Ambujakshan K.R. , Mathew Samuel , Ganguli Subarna , Nanda Ashis Kumar , Alsenoy Christian Van
Published: April 2009

Fourier transform infrared (FT‐IR) and Fourier transform (FT) Raman spectra of 3‐{[(2‐hydroxyphenyl)methylene]amino}‐2‐phenylquinazolin‐4(3H)‐one were recorded and analyzed. The vibrational wavenumbers of the title compound were computed using HF/6‐31G* and 6‐311G* basis sets and compared with experimental data. The assignments of the normal modes are done by potential energy distribution (PED)calculations. The prepared compound was identified by nuclear magnetic resonance (NMR) and mass spectra. Optimized geometrical parameters of the title compound are in agreement with reported structures. Shortening of CN bond lengths reveal the effect of resonance. The simultaneous IR and Raman activations of the CO stretching mode shows a charge transfer interaction through a π‐conjugated path. The first hyperpolarizability, infrared intensities and Raman activities are reported. The phenyl CC stretching modes are equally active as strong bands in both IR and Raman spectra, which are responsible for hyperpolarizability enhancement leading to nonlinear optical activity. Copyright © 2009 John Wiley & Sons, Ltd.
Audiometric, surgical, and genetic findings in 15 ears of patients with osteogenesis imperfecta
Authors: Swinnen Freya K.R. , De Leenheer Els M.R. , Coucke Paul J. , Cremers Cor W. R. J. , Dhooge Ingeborg J. M.
Published: April 2009

Objectives/Hypothesis:

To provide data on the outcome of stapes surgery in patients with osteogenesis imperfecta (OI). The audiometric results of 15 ears (12 patients), in which a stapes operation was performed, are presented and compared with results from literature.

Study Design:

Retrospective study.

Methods:

In 12 patients with genetically confirmed OI, intraoperative findings and audiometric evaluations were recorded.

Results:

In all patients the genetic mutation was located in the COL1A1 gene. Surgical findings in OI may be particular like mobile, atrophic stapes crura combined with a fixation of the stapes footplate, which may be thickened, and a hypervascularized or thickened middle‐ear mucosa. Outcome for hearing in 13 primary surgered ears was good because at short‐term follow‐up the air‐bone gap was reduced in all cases. These results were maintained in the long‐term, with exception of one ear, in which progression of the sensorineural component occurred shortly after the operation. Although initial success was noted in two ears with revision surgery, in the long term this was only maintained in one of them.

Conclusions:

In general, stapes surgery is successful in resolving the conductive hearing loss in OI patients, even in the long term. Hearing loss in OI is mostly of the mixed type, and the sensorineural component is reported to be progressive. Stapedotomy, by improving the hearing level, may facilitate the rehabilitation with a hearing aid. Because the identified mutation could be located in the COL1A1 gene in all patients, conductive hearing loss in OI caused by stapes fixation is possibly linked to a mutation in this gene. Laryngoscope, 2009
A coated electrode carrier for cochlear implantation reduces insertion forces
Authors: Radeloff Andreas , Unkelbach Marc H. , Mack Martin G. , Settevendemie Claudia , Helbig Silke , Mueller Joachim , Hagen Rudolf , Mlynski Robert
Published: April 2009

Objectives/Hypothesis:

To assess the insertion forces and feasibility of insertion of a prototype electrode carrier coated with a flexible and biodegradable coating developed for lubrication and drug delivery.

Study Design:

Experimental study.

Methods:

Eight coated and eight uncoated electrode carriers were inserted into a scala tympani model by means of an insertion device, and forces produced during insertion were determined in near real time. The maximum insertion depths and insertion angle were determined. To test the handling and operability, five coated electrode carriers were implanted into human temporal bones. Additionally, the bones were processed undecalcified and the distribution of the coating material within the cochlea evaluated.

Results:

Insertion forces were markedly reduced in the group of coated electrode carriers for insertion depths above 15 mm. The insertions were less fitful and led to a higher maximum insertion angle. The insertion of the coated electrode carrier was feasible, and the coating material was evident up to the apical parts of the cochlea postimplantation.

Conclusions:

Coating of a cochlear implant electrode carrier may reduce insertion forces responsible for the surgical trauma. Loaded with active substances, the coating may help to deliver drugs to the apical parts of the cochlear where hair cells reside in patients with residual hearing. Laryngoscope, 2009
Assessment of functioning in patients with head and neck cancer according to the International Classification of Functioning, Disability, and Health (ICF): A multicenter study
Authors: Tschiesner Uta , Linseisen Elisabeth , Baumann Sebastian , Siedek Vanessa , Stelter Klaus , Berghaus Alexander , Cieza Alarcos
Published: April 2009

Objectives:

To assess the level of functioning in patients with head and neck cancer (HNC) using the the International Classification of Functioning, Disability, and Health (ICF).

Methods:

Multicenter study at nine different study centers in four European countries. Data collection included structured interviews according to the extended ICF checklist with 145 HNC patients and completion of the European Organization for Research and Treatment of Cancer ‐ Quality of Life Questionnaires (EORTC‐QLQ). The generic ICF checklist was extended by additional HNC‐specific categories identified in six HNC‐specific questionnaires: EORTC, University of Washington Quality of Life (UW‐QOL), Functional Assessment of Cancer Therapy scale (FACT), Performance Status Scale for Head and Neck cancer patients (PSS‐HN), Head and Neck Quality of Life instrument (HN‐QOL), and Voice Handicap Index (VHI). The ICF qualifier system was applied on a scale from 0 (not impaired) to 4 (completely impaired), as well as “ns, na” (not specified, not applicable) and “c” (impaired due to comorbidity). ICF categories impaired due to HNC (1–4) in ≥10% of patients were reported.

Results:

One hundred fifteen (80%) of 144 categories of the extended ICF checklist were identified to be at least mildly impaired or restricted in ≥10% of patients. The four areas that were relevant to most of the patients were “immediate family” (91%), “friends” (86%), “health services and policies” (85%) and “health professionals” (85%), all belonging to the ICF component of environmental factors. The most often identified categories were “ingestion” (75%) for body functions and “speaking” (76%) for activities and participation. The summary score of all answers correlated well with the overall level of health and quality of life as assessed in the EORTC questionnaires (0.59, 0.61, respectively).

Conclusions:

The ICF identifies problems in functioning in patients with HNC comprehensively. The results emphasize the importance of contextual environmental factors. In particular, environmental factors referring to interpersonal support should be more strongly included in rehabilitation plans for HNC. Laryngoscope, 2009
Neural control of eustachian tube function
Authors: Songu Murat , Aslan Asim , Unlu H. Halis , Celik Onur
Published: April 2009

Objectives/Hypothesis:

It has been hypothesized that middle ear pressure can be controlled by the Eustachian tube through a neuronal reflex arc in animal models. We aimed to define the role of the neuronal control mechanisms in regulating middle ear pressure in humans.

Study Design:

Prospective study.

Methods:

The study population consisted of 95 ears of 95 volunteers. The mechanoreceptors on the tympanic membrane and the baroreceptors in the middle ear, which are assumed to form the afferent plexus of the neuronal reflex arc, were blocked by topical administration of lidocaine hydrochloride, in various patient groups. The Eustachian tube functions forming the efferent plexus of the neuronal reflex arc were evaluated by manometric tests both before and after blocking the possible afferent plexus in each study group.

Results:

The baroreceptors established in the tympanic plexus might possibly have an effective role in this mechanism where the mechanoreceptors on the tympanic membrane seem to have a minor effect.

Conclusions:

Neuronal control mechanism could play an important role in regulating Eustachian tube function in humans. Laryngoscope, 2009
Logarithmically improved regularity criteria for Navier–Stokes and related equations
Authors: Fan Jishan , Ozawa Tohru
Published: April 2009

We use an interpolation inequality on Besov spaces to show some logarithmically improved regularity criteria for Navier–Stokes equations, the harmonic heat flow, the Landau–Lifshitz equations, and the Landau–Lifshitz–Maxwell system. Copyright © 2009 John Wiley & Sons, Ltd.
Decreased gene expression of fibrillin‐1 in stress urinary incontinence
Authors: Söderberg Marie Westergren , Byström Birgitta , Hammarström Margareta , Malmström Anders , Ekman‐Ordeberg Gunvor
Published: April 2009

Aims

Studies to show impairments in the pelvic floor extracellular matrix (ECM) associated with stress urinary incontinence (SUI) has earlier been performed, but the results are contradictory. Collagen I and III, the elastin associated proteins fibrillin‐1 and fibulin‐5 and the small leucine‐rich repeat proteoglycans (SLRPs) decorin, lumican and fibromodulin are involved in giving the tissue its mechanical properties. Their gene signals and tissue localizations were investigated.

Methods

Para‐urethral punch biopsies were obtained from 24 women, 12 pre‐ and 12 postmenopausals, during surgery for SUI. As controls, biopsies were collected from 14 women, 8 pre‐ and 6 postmenopausals, undergoing surgery for other benign conditions. The mRNA expression by real‐time RT‐PCR and protein localization by immunohistochemistry were analyzed concerning collagen I and III, the small leucine rich repeat proteoglycans (SLRPs) decorin, lumican and fibromodulin and the elastic fiber associated proteins fibulin‐5 and fibrillin‐1. Statistical comparisons controlled for age changes in gene expressions.

Results

A significant decrease in mRNA expression of fibrillin‐1 was discovered in all SUI women compared to all controls, P = 0.03. All molecules were down‐regulated by age, but no other differences between SUI and controls reached significance. All proteins were adequately expressed by immunohistochemistry. A weaker staining for fibrillin‐1 was seen in the pre‐menopausal SUI group compared to the pre‐menopausal controls.

Conclusions

A decreased gene signal and weaker immunoreactivity for fibrillin‐1, important for the elastic fiber assembly, was discovered in women with SUI. Loss of tissue elasticity could lead to increased urethra hypermobility and SUI. Neurourol. Urodynam. 29:476–481, 2010. © 2009 Wiley‐Liss, Inc.
Conditions for effective large‐scale anticorruption efforts and the role of external actors: What does the Slovak experience tell us?
Authors: Beblavý Miroslav
Published: April 2009

The article looks at what policy‐makers can do to decrease corruption in developing and transition countries, based on an in‐depth examination of effectiveness of actual anticorruption measures in Slovakia. The research presents a synthesis of 12 case studies where measures in the sectors most associated with corruption as well as horizontal measures were analysed. The research shows that corruption can be decreased significantly within several years and external actors can play a substantial role in the process. An overall decrease in corruption can be based on aggregation of individual sectoral changes in areas most suffering from graft. In particular, the Slovak strategy was based on a sector‐by‐sector economic approach to resolve supply–demand imbalances based on either liberalisation/privatisation, limitations on discretion or managing supply and/or demand. Horizontal reforms complemented by sectoral reforms with their strong focus on increasing transparency. Concerning the role of external actors, we conclude that even when there is a domestically driven anticorruption effort, the external actors can still help significantly by serving as sources of inspiration, legitimacy, know‐how and funding for reform design and implementation. Copyright © 2009 John Wiley & Sons, Ltd.
c‐Jun amplification and overexpression are oncogenic in liposarcoma but not always sufficient to inhibit the adipocytic differentiation programme
Authors: Snyder Eric L , Sandstrom Deborah J , Law Kenneth , Fiore Christopher , Sicinska Ewa , Brito Joseph , Bailey Dyane , Fletcher Jonathan A , Loda Massimo , Rodig Scott J , Dal Cin Paola , Fletcher Christopher DM
Published: April 2009

Genomic amplification of c‐Jun and its upstream kinases have been implicated as a mechanism of progression from well‐differentiated to dedifferentiated liposarcoma. To further define the role of c‐Jun in liposarcoma progression, we performed immunohistochemistry for c‐Jun and its activating kinase ASK1 on a series of liposarcomas (n = 81). We correlated the results with fluorescence in situ hybridization to detect c‐Jun amplification. We also derived new cell lines from dedifferentiated liposarcomas with c‐Jun amplification. c‐Jun protein is expressed in the majority of dedifferentiated liposarcomas (91%) and their well‐differentiated components (59%), but only in the minority of pure well‐differentiated liposarcomas (27%). When c‐Jun is amplified in dedifferentiated liposarcoma, it is interspersed with amplified MDM2 on ring and giant marker chromosomes. MDM2 amplification is one of the earliest events in liposarcoma development, and these results suggest that c‐Jun was amplified at a similar time in the evolution of the tumour. In addition, shRNA to c‐Jun in c‐Jun‐amplified liposarcoma cells reduces cell number in vitro and inhibits tumour formation in vivo without an observable effect on the differentiation state of the liposarcoma cells. Thus, c‐Jun amplification is oncogenic in liposarcomas but not always sufficient for inhibition of adipocytic differentiation. Copyright © 2009 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.
Measuring social activities and social function in long‐term cancer survivors who received hematopoietic stem cell transplantation
Authors: Syrjala Karen L. , Stover Allison C. , Yi Jean C. , Artherholt Samantha B. , Abrams Janet R.
Published: April 2009

Objective: Cancer survivors report deficits in social functioning even years after completing treatment. Commonly used measures of social functioning provide incomplete understanding of survivors' social behavior. This study describes social activities of survivors and evaluates the psychometric properties of the Social Activity Log (SAL) in a cohort of long‐term survivors of hematopoietic stem cell transplantation (HSCT) for cancer.

Methods: One hundred and two (5–20 year) survivors completed the SAL, Short‐Form‐36 Health Survey (SF‐36), and other patient‐reported outcomes. Principal components analysis determined the factor structure of the SAL along with correlations and regressions to establish validity.

Results: Principal component analysis yielded three factors in the SAL: ‘non‐contact events’ (e.g. telephone calls), ‘regular events’ (e.g. played cards), and ‘special events’ (e.g. concerts), which explained 59% of the total variance. The SAL possessed good internal consistency (Cronbach'sα=0.82). SF‐36 social function and SAL were moderately correlated (r=0.31). In linear regressions, physical function and depression explained 16% of the variance in the SAL (P<0.001), while physical function, depression, and fatigue predicted 55% of the variance in SF‐36 social function (P<0.001).

Conclusions: Results support the use of the SAL as a measure of social activity in cancer survivors who received HSCT. Although the SAL is designed to measure social behaviors, SF‐36 social function assesses subjective experience and is more strongly associated with depression and fatigue. The SAL appears to be a promising tool to understand the behavioral social deficits reported by long‐term survivors of cancer. Copyright © 2009 John Wiley & Sons, Ltd.
Use of Nanodiamonds as a Reducing Agent in a Chlorate‐based Energetic Composition
Authors: Comet Marc , Pichot Vincent , Siegert Benny , Spitzer Denis , Moeglin Jean‐Pierre , Boehrer Yannick
Published: April 2009

To our knowledge, the incorporation of nanodiamond (nD) as a reducing agent in an energetic composition has never been reported in the literature. Diamond exhibits particularly interesting physico‐chemical properties: high density, good energetic potential, and relatively low thermal sensitivity. This study proposes to demonstrate that an explosive energetic composition can be obtained by physical mixing of nD and potassium chlorate (PC). First, the energetic characteristics of this formulation were compared to those of the famous “white powder” made of PC and saccharose and discovered by the French chemist Berthollet in the 18th century. In the second part, the combustion of pelletized nD‐based mixtures initiated by a laser beam was studied by time resolved cinematography. The deflagration velocity was measured on the most energetic composition, which has a slightly negative oxygen balance (OB=−30.1%).
The Kinetics of the Main Decomposition Process of Aminoguanidium 5,5′‐azobis‐1H‐tetrazolate
Authors: Miyata Yasuyoshi , Abe Masahiro , Date Shingo , Kohga Makoto , Hasue Kazuo
Published: April 2009

In this study, the kinetics of the thermal decomposition of aminoguanidinium 5,5′‐azobis‐1H‐tetrazolate (AGAT), which is one of the promising fuel candidates of the new gas generating agents for airbags, was investigated. The kinetic model that fits the main decomposition of AGAT was examined, and the activation energy was obtained. The main decomposition of AGAT was a single elementary process according to the result of mass spectrometry. The recommended kinetic model for the main decomposition of AGAT is Avrami–Erofeev equation (n=4). The activation energies for the main decomposition obtained under helium by non‐isothermal analysis and isothermal analysis were 207 and 209 kJ mol−1, respectively.
Manipulating glass for photonics
Authors: Fokine Michael
Published: April 2009

A generalized concept for local manipulation of three‐dimensional glass materials is described. The basic principle is to use means to deposit energy into the material to enable localized and selective changes in the bond structure of the glass matrix, causing a localized modification of the thermal equilibrium properties of the material. The different regions of the glass will then behave differently when the sample is subsequently heated homogeneously. If the difference in the thermal dynamics between modified and un‐modified regions is significant, thermal treatment of the material can result in a self‐organizing structure. The aim here is to provide a generalized concept of differential systems and self‐organizing structures, using chemical composition Bragg gratings as an example. In this case, differential diffusion results in self‐organizing structures consisting of a variation of the chemical composition, with compositional features smaller than 250 nm. (© 2009 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Proanthocyanidin protects against cisplatin‐induced nephrotoxicity
Authors: Sayed Ahmed Amir Radwan
Published: April 2009

Cisplatin (CP) [cis‐diamminedichloroplatinum (II)] is one of the most widely therapeutic agents used for treating many types of cancer. At effective doses, CP causes nephrotoxicity which has been attributed to the induction of reactive oxygen species (ROS). In the present investigation proanthocyanidin (PA) was studied to demonstrate its therapeutic efficacy against CP‐induced nephrotoxicity in mice. Cp treatment caused significant elevation of urea, creatinine and IL‐6. In addition, CP enhanced malondialdehyde (MDA) levels and lowered the glutathione (GSH) content in kidney. On the other hand, superoxide dismutase (SOD) activity was decreased. These alterations were reversed by PA in a dose‐dependent manner.

These findings suggested a beneficial role of PA in attenuating CP‐induced oxidative renal toxicity. Copyright © 2009 John Wiley & Sons, Ltd.
Aktualisierte Diagramme zur Bemessung von Stahlkonstruktionen für den Brandfall nach Eurocode 3
Authors: Mensinger Martin , Stadler Martin
Published: April 2009

Die Nachweise der Feuerwiderstandsfähigkeit von Stahlkonstruktionen nach Eurocode 3 [1] werden sich deutlich von den bislang in Deutschland gültigen Nachweisen nach DIN 4102 unterscheiden. Die Wahl der erforderlichen Brandschutzverkleidungen erfolgt nicht mehr zwingend vereinfacht über Tabellen. Das Tragwerk wird jetzt für den Brandfall bemessen, ähnlich dem Vorgehen bei Normaltemperatur. Dadurch können die sehr kostenintensiven Brandschutzmaßnahmen besser optimiert werden, in einigen Fällen kann nun sogar ganz auf Verkleidungen verzichtet werden. Die genauere Nachweisführung wird jedoch mit erhöhtem Rechenaufwand erkauft. Um diesen Aufwand zu minimieren, wurde in [3] bereits ein Bemessungshilfsmittel erarbeitet und in [4] vorgestellt, in dem die Nachweise des Eurocode grafisch aufbereitet wurden. Dieses basiert jedoch auf der Vornorm und kann aufgrund einiger Änderungen in der endgültigen Fassung nicht mehr angewendet werden. Deshalb werden hier aktualisierte Diagramme vorgestellt, welche dem aktuellen Stand der Normung angepasst sind. Zusätzlich wurden einige Diagramme ergänzt, um den Aufwand zur Brandschutzbemessung im Stahlbau nach Eurocode so gering wie möglich zu halten.
Synthesis and Crystal Structures of Axially Substituted Titaniumphthalocyanines and Preparation of PcTi@SBA‐15 and PcTi&TiOx@SBA‐15 Materials
Authors: Darwish Wael , Schlecht Sabine , Schaper Andreas , Fröba Michael , Harms Klaus , Massa Werner , Sundermeyer Jörg
Published: April 2009

Four axially substituted titanium(IV)phthalocyanines of formula trans‐[PcTi(OSiPh3)2], [PcTi{(NH)2C6H4}], [PcTi(η2‐S2)], and [PcTi=S] were prepared starting from the reactive species N,N′‐di‐4‐tolylureato(phthalocyaninato)titanium(IV). The prepared compounds were characterized by using UV/Vis‐spectroscopy, FT‐IR and raman spectroscopy, TGA, elementalanalysis and MALDI‐TOF measurements. The compound trans‐[PcTi(OSiPh3)2] crystallizes from chlorobenzene in the triclinic space group P$\bar{1}$ with a = 10.4160(8) Å, b = 11.2160(8) Å, c = 13.1495(9) Å, α = 114.124(5)°, β = 99.452(6)°, γ = 96.174(6)°, and Z = 1. [PcTiS2] crystallizes from chlorobenzene in the monoclinic space group P21/n with a = 13.114(3) Å, b = 9.752(2) Å, c = 20.975(5) Å, β = 100.46(2), and Z = 4. The crystal structures of both compounds are discussed. The reactive ureato complex could also successfully be anchored onto SBA‐15 and TiOx@SBA‐15 materials using the apical ureato ligand as a good leaving group for the reaction with the silanol groups of the host material.
The Synthesis and Luminescence of W6Cl12 and Mo6Cl12 Revisited
Authors: Ströbele Markus , Jüstel Thomas , Bettentrup Helga , Meyer H.‐Jürgen
Published: April 2009

The reduction of tungsten hexachloride with bismuth yields the new compound (BiCl)[W6Cl14]. Dissolution of this compound in HCl yields the cluster acid (H3O)2[W6Cl14]·7H2O and the new byproduct (H5O2)2[W6Cl12O6]·4H2O. The single‐crystal structures of all these compounds are reported. Their appearance provides some new insight into the mechanism and apparent problems of the synthesis of pure W6Cl12. Both Mo6Cl12 and W6Cl12 are strongly red luminescent materials.
A Truncated-Probit Item Response Model for Estimating Psychophysical Thresholds
Authors: Morey Richard D. , Rouder Jeffrey N. , Speckman Paul L.
Published: April 2009

Human abilities in perceptual domains have conventionally been described with reference to a threshold that may be defined as the maximum amount of stimulation which leads to baseline performance. Traditional psychometric links, such as the probit, logit, and t, are incompatible with a threshold as there are no true scores corresponding to baseline performance. We introduce a truncated probit link for modeling thresholds and develop a two-parameter IRT model based on this link. The model is Bayesian and analysis is performed with MCMC sampling. Through simulation, we show that the model provides for accurate measurement of performance with thresholds. The model is applied to a digit-classification experiment in which digits are briefly flashed and then subsequently masked. Using parameter estimates from the model, individuals’ thresholds for flashed-digit discrimination is estimated.
Global well-posedness and scattering for the derivative nonlinear Schrödinger equation with small rough data
Authors: Wang Baoxiang , Han Lijia , Huang Chunyan
Published: April 2009

We study the Cauchy problem for the generalized elliptical and non-elliptical derivative nonlinear Schrödinger equations (DNLS) and get the global well posedness of solutions with small data in modulation spaces

M_{2,1}^{s}(\mathbb{R}^{n})

. Noticing that

B_{2,1}^{s + n/ 2} \subset M_{2,1}^{s} \subset B_{2,1}^{s}

are optimal inclusions, we have shown the global well posedness of DNLS with a class of rough data. As a by-product, the existence of the scattering operators in modulation spaces with small data is also obtained.
Die nichtinvasive Bilddiagnostik der koronaren Herzkrankheit
Authors: Zuber Michel , Zellweger Michael , Bremerich Jens , Auf der Mauer Christoph , Buser Peter T.
Published: April 2009

Die nicht invasive Diagnostik der koronaren Herzkrankheit hat sich in den letzten Jahren stark gewandelt und es stehen mehrere Methoden mit hoher Bildqualität wie die Echokardiographie, die Myokardszintigraphie, die kardiale Magnetresonanz und die kardiale Computertomographie zur Verfügung, um die Diagnose einer koronaren Herzkrankheit zu sichern, lebensfähiges von totem Myokard zu unterscheiden und das Risiko für zukünftige ischämische Ereignisse einzuschätzen. Welche der verfügbaren Methoden zur Beantwortung welcher Fragestellung bezüglich der diagnostischen Genauigkeit als auch der Kosteneffizienz am besten ist, ist für den Grundversorger schwierig zu werten. Der Artikel gibt einen Überblick über die aktuelle Wertigkeit sowie die Vor- und Nachteile der einzelnen Methoden bei der Abklärung der koronaren Herzkrankheit im klinischen Alltag.
Die Rolle der perkutanen Koronarintervention in der Behandlung der koronaren Herzkrankheit
Authors: Lepper Philipp M. , Windecker Stephan , Meier Bernhard
Published: April 2009

In den Industriestaaten bleiben kardiovaskuläre Erkrankungen die Todesursache Nummer eins. Diese Übersichtsarbeit fasst die Rolle der perkutanen Koronarintervention in der Behandlung der koronaren Herzkrankheit zusammen. Die interventionelle Therapie der koronaren Herzkrankheit wurde mit der Ballondilatation durch Andreas Grüntzig 1977 in Zürich initiiert. Technische Fortschritte der perkutanen Koronardilatation (PCI) betrafen seither Konstruktion und Materialien der Führungskatheter, der Führungsdrähte und der Ballons, aber auch die Röntgentechnologie mit Einführung der digitalen Bildverarbeitungen und die filmlose Archivierung. Ergänzende Methoden – Rotablation, Atherektomie, Laser, Ultraschall und die Stentimplantation – wurden entwickelt. Lediglich Stents haben das Verfahren grundlegend verändert. Sie sind heute fester Bestandteil der PCI.
Rolle der Bypasschirurgie in der Behandlung der koronaren Herzkrankheit – eine ausgewogene Information des Patienten und objektive Entscheidungskriterien sind erwünscht
Authors: Carrel Thierry , Eckstein Friedrich , Turina Marko
Published: April 2009

In den letzten zwei Jahren ist die Diskussion über die optimale Behandlung der koronaren Herzkrankheit (Vor- und Nachteile der interventionellen versus chirurgische Behandlung) als Folge von negativen Erfahrungen mit beschichteten Stents glücklicherweise wieder aufgenommen worden. Die chirurgische Revaskularisation des Myokardes hat in vielen Studien ihre langfristige Überlegenheit gegenüber der interventionellen Methode, insbesondere bei schwerem Befall (3-Gefäßerkrankung und Hauptstammstenose) bewiesen. Etliche prospektiv randomisierte Studien, die vergleichbare kurz- und mittelfristige Resultate nach PCI und CABG zeigen, sind in ihrer Patientenrekrutierung äußerst restriktiv, so dass kaum mehr als 5% aller Patienten eingeschlossen werden. Die Bypassoperation bietet eine vollständige Revaskularisation mit einem langfristigen Schutz dank der Versorgung aller befallenen Gefäße in ihrem distalen Versorgungsabschnitt. Immer häufiger werden arterielle Conduits verwendet, mit einer ausgezeichneten Durchgängigkeitsrate (weit über 90% nach 10–15 Jahren für die Art. mammaria). Mit einer früh-postoperativen Mortalität zwischen 0.6% und 1% (rapportierte Zahlen aus den Kliniken für Herz- und Gefäßchirurgie des Inselspitals in Bern und des Universitätsspitals in Zürich) bleibt die chirurgische Bypassmethode sehr konkurrenzfähig und in der Praxis auf längere Sicht (> 3 Jahre) kostengünstiger als die Anwendung multipler, sehr teueren Stents. Bei der breiten Anwendung der kathetertechnischen Möglichkeiten sollte im Allgemeinen vorsichtiger umgegangen werden und von einer ausufernden Anwendung beschichteten Stents im Besonderen gewarnt werden. Patienten, Gesundheitsexperten und Kostenträger müssen besser und ehrlicher informiert werden und die gemeinsame Beurteilung von Patienten mit KHK in einem Team von Kardiologen und Herzchirurgen, die an vielen Kliniken verloren gegangen ist, sollte dringend wieder eingeführt oder intensiver gelebt werden. Zum Zeitpunkt der Einführung von interventionellen Klappeneingriffen scheint diese Forderung mehr als gerechtfertig
Role of Hydrogen Peroxide and the Impact of Glutathione Peroxidase-1 in Regulation of Cerebral Vascular Tone
Authors: Modrick Mary L , Didion Sean P , Lynch Cynthia M , Dayal Sanjana , Lentz Steven R , Faraci Frank M
Published: April 2009

Although arachidonic acid (AA) has diverse vascular effects, the mechanisms that mediate these effects are incompletely defined. The goal of our study was to use genetic approaches to examine the role of hydrogen peroxide (H2O2), glutathione peroxidase (Gpx1, which degrades H2O2), and CuZn-superoxide dismutase (SOD1, which produces H2O2from superoxide) in mediating and in determining vascular responses to AA. In basilar arteries in vitro, AA produced dilation in nontransgenic mice, and this response was reduced markedly in transgenic mice overexpressing Gpx1 (Gpx1 Tg) or in those genetically deficient in SOD1. For example, AA (1 nmol/L to 1 μmol/L) dilated the basilar artery and this response was reduced by ∼90% in Gpx1 Tg mice ( P<0.01), although responses to acetylcholine were not altered. Dilation of cerebral arterioles in vivo in response to AA was inhibited by ∼50% by treatment with catalase (300 U/mL) ( P<0.05) and reduced by as much as 90% in Gpx1 Tg mice compared with that in controls ( P<0.05). These results provide the first evidence that Gpx1 has functional effects in the cerebral circulation, and that AA-induced vascular effects are mediated by H2O2produced by SOD1. In contrast, cerebral vascular responses to the endothelium-dependent agonist acetylcholine are not mediated by H2O2.
Molecular basis of the inhibitor selectivity and insights into the feedback inhibition mechanism of citramalate synthase from Leptospira interrogans
Authors: Zhang Peng , Ma Jun , Zhang Zilong , Zha Manwu , Xu Hai , Zhao Guoping , Ding Jianping
Published: April 2009

LiCMS (Leptospira interrogans citramalate synthase) catalyses the first reaction of the isoleucine biosynthesis pathway in L. interrogans, the pathogen of leptospirosis. The catalytic reaction is regulated through feedback inhibition by its end product isoleucine. To understand the molecular basis of the high selectivity of the inhibitor and the mechanism of feedback inhibition, we determined the crystal structure of LiCMSC (C-terminal regulatory domain of LiCMS) in complex with isoleucine, and performed a biochemical study of the inhibition of LiCMS using mutagenesis and kinetic methods. LiCMSC forms a dimer of dimers in both the crystal structure and solution and the dimeric LiCMSC is the basic functional unit. LiCMSC consists of six β-strands forming two anti-parallel β-sheets and two α-helices and assumes a βαβ three-layer sandwich structure. The inhibitor isoleucine is bound in a pocket at the dimer interface and has both hydrophobic and hydrogen-bonding interactions with several conserved residues of both subunits. The high selectivity of LiCMS for isoleucine over leucine is primarily dictated by the residues, Tyr430, Leu451, Tyr454, Ile458 and Val468, that form a hydrophobic pocket to accommodate the side chain of the inhibitor. The binding of isoleucine has inhibitory effects on the binding of both the substrate, pyruvate, and coenzyme, acetyl-CoA, in a typical pattern of K-type inhibition. The structural and biochemical data from the present study together suggest that the binding of isoleucine affects the binding of the substrate and coenzyme at the active site, possibly via conformational change of the dimer interface of the regulatory domain, leading to inhibition of the catalytic reaction.
New statistical methods for the evaluation of cardiovascular risk markers: what the clinician should know
Authors: Røsjø Helge , Omland Torbjørn
Published: April 2009

Calculation of odds ratios or hazard ratios by multivariate logistic regression or Cox regression analyses have traditionally been used to show that candidate risk markers provide prognostic information independently of conventional risk markers, but it has become increasingly clear that a statistically significant increase in risk in multivariate models may not represent a clinically meaningful improvement in overall prediction. This observation has prompted the development of more clinically relevant statistical methods, including tests of the ability to provide incremental discrimination compared with traditional risk markers by calculation of the C-statistic (corresponding to the area under the receiver operating curve) of the model and methods for evaluating improvement in risk classification by the use of event-specific re-classification tables or the use of the integrated discrimination improvement. In the present issue of Clinical Science, Khan and co-workers have evaluated the prognostic value of the GRACE (Global Registry of Acute Coronary Events) risk score, the cardiac biomarker NT-proBNP (N-terminal pro-B-type natriuretic peptide), and their combination, for the prediction of mortality after acute myocardial infarction, using a combination of statistical methods.
Volume contribution to perpendicular anisotropy in Fe0.5Co0.5 alloy films on Pd(001), Ir(001), and Rh(001)
Authors: Yildiz F. , Przybylski M. , Kirschner J.
Published: April 2009

In tetragonally distorted Fe0.5Co0.5 alloy films grown epitaxially on Pd(001), Ir(001), and Rh(001) substrates the crystal field locates the electronic states near the Fermi level (EF) with one being below EF and the other above EF with an energy separation smaller than in bulk nondistorted material. This results in a strong uniaxial anisotropy and an easy magnetization axis perpendicular to the film plane up to the thickness up to which the films remain tetragonally distorted. The strongest perpendicular anisotropy is achieved when the Fe0.5Co0.5 films are grown on Rh(001) (c/a=1.24); it systematically decreases for Ir(001) (c/a=1.18) and Pd(001) (c/a=1.13) substrates. The phenomenon can be understood as a result of an increasing uniaxial anisotropy with an increasing c/a ratio up to the maximum at c/a=1.24 for which the maximum uniaxial magnetic anisotropy has been theoretically predicted.
Hot carrier solar cells operating under practical conditions
Authors: Takeda Yasuhiko , Ito Tadashi , Motohiro Tomoyoshi , König Dirk , Shrestha Santosh , Conibeer Gavin
Published: April 2009

We theoretically investigated the features of hot carrier solar cells, from which photogenerated carriers are extracted before they are completely thermalized. There are three channels of energy dissipation from photogenerated carriers that lowers the conversion efficiency: thermalization in the absorber, emission from the absorber, and thermodynamically unavoidable heat flux to the ambient. The emission increases with increasing carrier density in the absorber, whereas the heat flux decreases. Previous calculations of the conversion efficiency have been carried out under the supposition of no thermalization of carriers. In this case, the dominant process of energy dissipation is the emission, like conventional solar cells represented by the Shockley and Queisser formula. In practice, the carriers should be extracted to external circuits immediately after photogeneration because they are partially thermalized. This restriction leads to a much smaller carrier density and consequently more significant energy dissipation by heat flux, whereas the influence of the emission is negligible. As a result, the conversion efficiency is considerably lower than the values under the supposition of no thermalization. To suppress the heat flux to improve conversion efficiency, a smaller effective electron mass and a higher carrier temperature are required, as well as more intense irradiation. When the effective electron mass is much smaller than that of holes, the thermalization of holes has little influence on lowering the conversion efficiency.
The change in permeability spectra due to ion irradiation in the Co-based amorphous ribbon
Authors: Park D. G. , Park C. Y. , Song H. , Kim C. G. , Cheong Y. M.
Published: April 2009

The Ar ion has been irradiated by an ion implanter with energy of 50, 70, and 100 keV and an ion dosage was set to 1.0×1017 ion/cm2 at a beam flux of 3.7 μA/cm2. The ion irradiation decreased the initial permeability and increased the relaxation frequency, and the behavior of permeability spectra due to ion irradiation was explained with damped harmonic model of domain wall on the general basis of magnetization mechanism. The ion irradiation gives rise to a significant change on the restoring force of domain wall but minor effect on the spin rotation. The enhancement in the permeability of the amorphous ribbon upon ion irradiation leads to a parallel improvement of giant magneto impedance response of the material, which is of practical use for sensing applications.
Bulklike structures for medium-sized Aln (n=31–40) clusters
Authors: Zhang Wei , Lu Wen-Cai , Zang Qing-Jun , Wang C. Z. , Ho K. M.
Published: April 2009

Neutral aluminum clusters Aln (n=31–40) were studied using a genetic algorithm (GA)/tight-binding (TB) search combined with DFT-PBE calculations. It is found that the medium-sized aluminum clusters Al31 to Al40 exhibit a bulklike stacking pattern. Anion clusters were also studied.
Approximate ternary Jordan derivations on Banach ternary algebras
Authors: Savadkouhi M. Bavand , Gordji M. Eshaghi , Rassias J. M. , Ghobadipour N.
Published: April 2009

Let A be a Banach ternary algebra over a scalar field R or C and X be a ternary Banach A-module. A linear mapping D:(A,[ ]A)→(X,[ ]X) is called a ternary Jordan derivation if D([xxx]A)=[D(x)xx]X+[xD(x)x]X+[xxD(x)]X for all x∊A. In this paper, we investigate ternary Jordan derivations on Banach ternary algebras, associated with the following functional equation f((x+y+z)/4)+f((3x−y−4z)/4)+f((4x+3z)/4)=2f(x). Moreover, we prove the generalized Ulam–Hyers stability of ternary Jordan derivations on Banach ternary algebras.
Interplay between structural and magnetic properties of L1-FePt(001) thin films directly grown on MgO(001)
Authors: Laenens B. , Almeida F. M. , Planckaert N. , Temst K. , Meersschaut J. , Vantomme A. , Rentenberger C. , Rennhofer M. , Sepiol B.
Published: April 2009

We present a detailed study of the magnetic and structural properties of L10-FePt thin films. The films are prepared via molecular beam epitaxy directly onto MgO(001) substrates, i.e., without buffer layer. Despite the large lattice misfit between the in-plane lattice parameters of L10 FePt and MgO, highly ordered thin films are obtained with the easy magnetization c axis perpendicular to the film plane. Via high resolution transmission electron microscopy and Rutherford backscattering measurements we focus on the FePt/MgO interface to study the misfit relaxation and the defect density. Further, the influence of elevated substrate temperatures and of postgrowth high temperature annealing on the structural and magnetic properties is discussed.
Electron acoustic waves in pure ion plasmas
Authors: Anderegg F. , Driscoll C. F. , Dubin D. H. E. , O’Neil T. M. , Valentini F.
Published: April 2009

Standing electron acoustic waves (EAWs) are observed in a pure ion plasma. EAWs are slow nonlinear plasma waves; at small amplitude their phase velocities (vph≃1.4v¯ for small kλD) and their frequencies are in agreement with theory. At moderate amplitude, EAW-type plasma waves can be excited over a broad range of frequencies. This frequency variability comes from the plasma adjusting its velocity distribution so as to make the plasma mode resonant with the drive frequency. Wave-coherent laser-induced fluorescence shows the intimate nature of the wave-particle interaction, and how the particle distribution function is modified by the wave driver until the plasma mode is resonant with the driver.
Accurate ab initio double many-body expansion potential energy surface for ground-state H2S by extrapolation to the complete basis set limit
Authors: Song Y. Z. , Varandas A. J. C.
Published: April 2009

A single-sheeted potential energy surface is reported for the electronic ground-state of H2S by fitting accurate multireference configuration interaction energies calculated using aug-cc-pVTZ and aug-cc-pVQZ basis sets with extrapolation of the electron correlation energy to the complete basis set limit, plus extrapolation to the complete basis set limit of the complete-active-space self-consistent field energy. A switching function formalism has been used to warrant the correct behavior at the H2(X Σ1g+)+S(D1) and SH(X Π2)+H(S2) dissociation limits. The topographical features of the novel global potential energy surface are examined in detail, with the former being used for exploratory quasiclassical trajectory calculations of the thermal rate constant for the S(D1)+H2, S(D1)+D2, and S(D1)+HD reactions at room temperature. A comparison with other available potential energy surfaces as well as kinetics data is also provided.
Effects of line tying on resistive tearing instability in slab geometry
Authors: Huang Yi-Min , Zweibel Ellen G.
Published: April 2009

The effects of line tying on resistive tearing instability in slab geometry are studied within the framework of reduced magnetohydrodynamics [B. B. Kadomtsev and O. P. Pogutse, Sov. Phys. JETP 38, 283 (1974); H. R. Strauss, Phys. Fluids 19, 134 (1976)]. It is found that line tying has a stabilizing effect. The tearing mode is stabilized when the system length L is shorter than a critical length Lc, which is independent of the resistivity η. When L is not too much longer than Lc, the growth rate γ is proportional to η. When L is sufficiently long, the tearing mode scaling γ∼η3/5 is recovered. The transition from γ∼η to γ∼η3/5 occurs at a transition length Lt∼η−2/5.
Excited level populations and excitation kinetics of nonequilibrium ionizing argon discharge plasma of atmospheric pressure
Authors: Akatsuka Hiroshi
Published: April 2009

Population densities of excited states of argon atoms are theoretically examined for ionizing argon plasma in a state of nonequilibrium under atmospheric pressure from the viewpoint of elementary processes with collisional radiative model. The dependence of excited state populations on the electron and gas temperatures is discussed. Two electron density regimes are found, which are distinguished by the population and depopulation mechanisms for the excited states in problem. When the electron impact excitation frequency for the population or depopulation is lower than the atomic impact one, the electron density of the plasma is considered as low to estimate the population and depopulation processes. Some remarkable characteristics of population and depopulation mechanisms are found for the low electron density atmospheric plasma, where thermal relaxation by atomic collisions becomes the predominant process within the group of close-energy states in the ionizing plasma of atmospheric pressure, and the excitation temperature is almost the same as the gas temperature. In addition to the collisional relaxation by argon atoms, electron impact excitation from the ground state is also an essential population mechanism. The ratios of population density of the levels pairs, between which exists a large energy gap, include information on the electron collisional kinetics. For high electron density, the effect of atomic collisional relaxation becomes weak. For this case, the excitation mechanism is explained as electron impact ladderlike excitation similar to low-pressure ionizing plasma, since the electron collision becomes the dominant process for the population and depopulation kinetics.