bluuebunny/crossref_metadata_2025 huggingface dataset:
Binaural measurement of bone conduction click evoked otoacoustic emissions in adults and infants
Authors: Kandzia Florian , Oswald Johann , Janssen Thomas
Published: March 2011

Transient evoked otoacoustic emissions (TEOAEs) are usually evoked with air conduction (AC) stimuli. Only a few reports exist about OAEs where stimuli have been delivered using bone conduction (BC) by placing a bone conductor on the forehead or the mastoid. The aims of the present study were to improve the test performance of BC-TEOAEs by using a nonlinear stimulation protocol and to find out, whether this technique can be applied in newborn hearing screening. BC-TEOAEs were measured binaurally in ten normal hearing adults and in ten infants. For measurements in infants, miniaturized probes without loudspeakers were constructed to allow a complete insertion of the probe in the infant’s ear canal. It could be shown that robust and valid BC-TEOAEs can be elicited using a nonlinear stimulation protocol. Findings in adults indicated that BC-TEOAEs can be measured with properties similar to AC-TEOAEs. However, mean BC-TEOAE levels were reduced by 0.8–3.7 dB depending on frequency. In view of test time, this is compensated by performing binaural recordings. Measurements in infants indicated that the screening performance of BC-TEOAEs and AC-TEOAEs may be comparable. Further studies have to investigate, whether BC-TEOAEs are more robust than AC-TEOAEs against small conductive hearing loss.
Lateralization produced by envelope-based interaural temporal disparities of high-frequency, raised-sine stimuli: Empirical data and modeling
Authors: Bernstein Leslie R. , Trahiotis Constantine
Published: March 2011

An acoustic pointing task was used to measure extents of laterality produced by ongoing interaural temporal disparities (ITDs) conveyed by the envelopes of 4-kHz-centered raised-sine stimuli while varying, parametrically, their peakedness, depth of modulation, and frequency of modulation. One purpose of the study was to determine whether such manipulations would produce changes in laterality logically consistent with those found for ITD-discrimination thresholds reported by Bernstein and Trahiotis [J. Acoust. Soc. Am. 125, 3234–3242 (2009)]. The data obtained revealed that they did in that (1) increasing depth of modulation, peakedness, or frequency of modulation between 32 and 128 Hz produced smaller threshold ITDs and greater laterality and (2) increasing frequency of modulation to 256 Hz produced modest increases in threshold ITDs and modest decreases in laterality. The extents of laterality measured were successfully accounted for via an augmentation of the cross-correlation-based “position-variable” modeling approach developed by Stern and Shear [J. Acoust. Soc. Am. 100, 2278–2288 (1996)] to account for ITD-based extents of laterality obtained at low spectral frequencies.
Masked detection and discrimination of tone sequences under conditions of monaural and binaural masking release
Authors: Hall Joseph W. , Buss Emily , Grose John H.
Published: March 2011

Experiment I examined detection and discrimination of monaural four-tone sequences composed of 400-, 500-, and 625-Hz sinusoids. In the baseline conditions, the masker was monaural composed of 25-Hz-wide bands of random noise centered on 320, 400, 500, 625, and 781 Hz. In the binaural masking release conditions, the noise was presented diotically. In the monaural masking release conditions, the noise was presented to the same ear as the signal, but it was comodulated. Tones had half-amplitude durations of 30, 60, or 150 ms. There was no delay between successive tones, so the rate of frequency change depended on tone duration. Listeners discriminated between sequences composed of 500–400–625–500 Hz and 500–625–400–500 Hz. Discrimination results were poor for rapid sequences in both monaural and binaural masking release conditions relative to baseline conditions. Results from experiment II indicated that poor discrimination for rapid sequences could also occur in the baseline conditions, provided that the frequency separation among tonal components was small. Sluggish processing in the present paradigm was not restricted to conditions relying on binaural cues. It is argued that sluggishness may reflect a long temporal window in monaural and binaural masking release conditions or an interaction between poor cue quality and task difficulty.
A candidate mechanism for exciting sound during bubble coalescence
Authors: Czerski Helen
Published: March 2011

Coalescing bubbles are known to produce a pulse of sound at the moment of coalescence, but the mechanism driving the sound production is uncertain. A candidate mechanism for the acoustic forcing is the rapid increase in the bubble volume, as the neck of air joining the two parent bubbles expands. A simple model is presented here for the volume forcing caused by the coalescence dynamics, and its predictions are tested against the available data. The model predicts the right order of magnitude for the acoustic amplitude, and the predicted amplitudes also scale correctly with the radius of the smaller parent bubble.
ACOUSTICAL STANDARDS NEWS
Authors: Blaeser Susan B. , Schomer Paul D.
Published: March 2011

American National Standards (ANSI Standards) developed by Accredited Standards Committees S1, S2, S3, and S12 in the areas of acoustics, mechanical vibration and shock, bioacoustics, and noise, respectively, are published by the Acoustical Society of America (ASA).In addition to these standards, ASA publishes catalogs of Acoustical Standards, both National and International.To receive copies of the latest Standards catalogs, please contact Susan B. Blaeser.

Comments are welcomed on all material in Acoustical Standards News.

This Acoustical Standards News section in JASA, as well as the National and International Catalogs of Acoustical Standards, and other information on the Standards Program of the Acoustical Society of America, are available via the ASA home page: http://acousticalsociety.org.
Deduction of static surface roughness from complex excess attenuation
Authors: Nichols Andrew , Attenborough Keith , Taherzadeh Shahram
Published: March 2011

Data for complex excess attenuation have been used to determine the effective surface admittance and hence characteristic roughness size of a surface comprising a random distribution of semi-cylindrical rods on an acoustically hard plane. The inversion for roughness size is based on a simplified boss model. The technique is shown to be effective to within 4%, up to a threshold roughness packing density of 32%, above which the interaction between scattering elements appears to exceed that allowed by the model.
Kepler Detected Gravity-Mode Period Spacings in a Red Giant Star
Authors: Beck P. G. , Bedding T. R. , Mosser B. , Stello D. , Garcia R. A. , Kallinger T. , Hekker S. , Elsworth Y. , Frandsen S. , Carrier F. , De Ridder J. , Aerts C. , White T. R. , Huber D. , Dupret M.-A. , Montalbán J. , Miglio A. , Noels A. , Chaplin W. J. , Kjeldsen H. , Christensen-Dalsgaard J. , Gilliland R. L. , Brown T. M. , Kawaler S. D. , Mathur S. , Jenkins J. M.
Published: March 2011

Asteroseismology Delivers

Using asteroseismology—the study of stellar oscillations, it is possible to probe the interior of stars and to derive stellar parameters, such as mass and radius (see the Perspective by

Montgomery

). Based on asteroseismic data from the NASA Kepler mission,

Chaplin
et al.

(p.
213
) detected solarlike oscillations in 500 solartype stars in our Galaxy. The distribution of the radii of these stars matches that expected from stellar evolution theory, but the distribution in mass does not, which challenges our knowledge of star formation rates, the mass of forming stars, and the models of the stars themselves.

Derekas
et al.

(p.
216
) report the detection of a triple-star system comprising a red giant star and two red dwarfs. The red giant star, instead of the expected solarlike oscillations, shows evidence for tidally induced oscillations driven by the orbital motion of the red dwarf pair. Finally,

Beck
et al.

(p.
205
) describe unusual oscillations from a red giant star that may elucidate characteristics of its core.
Clinicopathological significance and prognostic value of EphA3 and CD133 expression in colorectal carcinoma
Authors: Xi Hong-Qing , Zhao Po
Published: March 2011

Aims

To investigate clinicopathological significance and prognostic implications of EphA3, CD133 and Ki-67 expression in colorectal cancer.

Methods

EphA3, CD133 and Ki-67 expression was assessed in 201 cases of paraffin-embedded colorectal carcinoma and 60 cases of distal normal mucosal tissue by immunohistochemistry. Medical records were reviewed and clinicopathological analysis was performed. The differential expression of EphA3 and CD133 protein was detected in 20 cases of fresh resected colorectal carcinoma and 20 cases of matched normal mucosal tissue adjacent to the carcinoma by western blot.

Results

The expression of EphA3 and CD133 in carcinoma was significantly higher than that in normal mucosal tissue (p=0.008; p=0.004). EphA3 and CD133 were positively correlated with tumour size (p=0.029; p=0.017), histological grade (all p=0.001), infiltrative depth (all p=0.00), lymph node metastasis (all p=0.00), distant metastasis (p=0.017; p=0.030) and TNM stage (all p=0.001). Patients with high expression of EphA3 and CD133 had the lowest survival (all p=0.001) (median survival time of EphA3 positive and negative cases: 34.0 and 72.0 months; median survival time of CD133 positive and negative cases: 34.0 and 77.0 months). Multivariate survival analysis showed that EphA3 and CD133 expression was correlated significantly with shortened survival in patients with colorectal cancer (Cox regression: p=0.001, HR=4.722, 95% CI 2.667 to 8.361; p=0.001, HR=5.224, 95% CI 2.622 to 10.405). EphA3, CD133 and Ki-67 expression in colorectal cancer had positive correlations with each other (all p=0.001).

Conclusions

EphA3 and CD133 may play an important role in the development and progression of tumours, and thus become useful indicators for clinical assessment of tumour biological behaviour and prognosis in patients with colorectal carcinoma.
Structure and molecular evolution of the ribosomal DNA external transcribed spacer in the cockroach genusBlattella
Authors: Mukha Dmitry V. , Mysina Vera , Mavropulo Valeria , Schal Coby
Published: March 2011

The ribosomal DNA (rDNA) cluster of insects contains several hundred repeating structural–functional units and, therefore, is a typical example of a multigene family. Eukaryotic ribosomal RNA (rRNA) genes (18S, 5.8S, and 28S like) are arranged in tandemly repeated clusters in the nucleolus organizers, separated by several spacers, namely the nontranscribed spacer, the external transcribed spacer (ETS), and the internal transcribed spacers. The nucleotide sequences of the ETS of the three closely related Blattella cockroach species, Blattella germanica (Linnaeus, 1767), Blattella asahinai (Mizukubo, 1981), and Blattella lituricollis (Walker, 1868), were determined and compared. The three species had relatively similar ETS lengths, and sequence differences among them could be explained by two types of rearrangements, namely deletions of subrepeats and nucleotide substitutions. Minor ETS variants in B. germanica differed from the major variant in the same way that the major ETS variants of the three Blattella species differed from each other. Concerted evolution and the birth-and-death models, which are often invoked to explain the diversity and evolution of the multigene families of rDNA clusters, are discussed in the light of our data. A new model is proposed to explain the evolutionary reorganization of the ETS region: evolution of rDNA by “magnification-and-fixation” is characterized by magnification of minor subrepeats, which become adaptive in a new rapidly changed environment, and subsequent fixation of this variant type as a major component of the multigene family of a new species.
Population-specific quantitative trait loci mapping for functional stay-green trait in rice (Oryza sativaL.)
Authors: Fu Jin-Dong , Yan Yong-Feng , Kim Moon Young , Lee Suk-Ha , Lee Byun-Woo
Published: March 2011

The functional stay-green trait gives leaves a longer duration of greenness and photosynthetic capacity during the grain-filling period. We developed two independent recombinant inbred line populations from the intra- and intersubspecific crosses of Oryza sativa L. subsp. japonica ‘Suweon490’ (japonica) × O. sativa subsp. japonica ‘SNU-SG1’ (japonica) and O. sativa subsp. indica ‘Andabyeo’ (indica) × O. sativa subsp. japonica ‘SNU-SG1’ (japonica), respectively. The common parental line ‘SNU-SG1’ was the functional source for the stay-green trait. Quantitative trait locus (QTL) mapping based on simple sequence repeat markers identified a total of six QTLs associated with two stay-green traits across two populations. The two traits were cumulative chlorophyll content (SPAD value) of flag leaf (CSFL) and total cumulative SPAD value of the four upper leaves (TCS). Four QTLs, tcs4, csfl6, csfl9 (or tcs9), and csfl12, located on chromosomes 4, 6, 9, and 12, respectively, were detected simultaneously in both populations. The remaining two QTLs, csfl2 (or tcs2) and tcs5, on chromosomes 2 and 5, respectively, were found to be population specific. Moreover, the functional stay-green trait of ‘SNU-SG1’ positively correlated with grain yield performance. Two yield QTLs, yld6 and yld9, on chromosomes 6 and 9 found in both populations were positioned at the same locations with the csfl6 and tcs9 QTLs for stay-green traits. Thus, the identified chromosomal regions can be promising targets of marker-assisted introgression of the functional stay-green trait into breeding materials for improvement of rice yield.
Studies on the determination of swelling properties of soils from suction measurements
Authors: Rao B. Hanumantha , Venkataramana K. , Singh D. N.
Published: March 2011

Expansive soils exhibit significantly high volumetric deformations and hence, pose a serious threat to stability of structures and foundations. As such, determination of their swelling properties (viz., swelling potential and swelling pressure) becomes essential. Earlier researchers have developed various experimental techniques, and empirical relationships based on the results obtained from these investigations, for determining swelling characteristics of these soils. However, although these techniques help in direct estimation of the swelling properties of soils, the instrumentation is quite cumbersome and time consuming. This limitation can be overcome by measuring soil suction, which would also yield its swelling characteristics, though indirectly, but quite rapidly and easily. To demonstrate the utility and ease of application of this methodology, attempts were made in the present study to establish swelling properties of expansive soils from their suction measurements. Details of the methodology adopted are presented and results have been critically evaluated vis-à-vis those available in the literature.
Physical and numerical modelling of a dual-porosity fractured rock surrounding an in-pit uranium tailings management facility
Authors: Lange K. , Van Geel P. J.
Published: March 2011

In-pit tailings management facilities (TMFs) have been used to dispose of uranium mine tailings in northern Saskatchewan. The pervious surround method can be employed to reduce groundwater flow through the tailings, and thereby moderate the rate of flux of radioactive and metal contamination that could enter the local groundwater via advection. A laboratory-scale analogue of an in-pit TMF was constructed to evaluate the impacts of a dual-porosity representation of the host rock on the effectiveness of the pervious surround concept in reducing peak concentrations and mass flux at a downgradient receptor. This work complemented the work of West et al. (2003) in which similar laboratory-scale experiments were conducted, simulating the host rock using the equivalent porous media and discrete fracture approaches. The experiments were adequately simulated using SWIFT II, a dual-porosity flow and transport model. Finally, to illustrate the impact of a dual-porosity representation of a fractured host rock on a contaminant plume from a TMF in the field, a field-scale scenario was modelled. The simulations illustrate the impact of diffusion into the host rock matrix on the simulated peak concentrations and the time for the peak concentrations to reach a downgradient receptor.
Intramolecular H-atom transfer reactions in rigid peptides — Correlated solvent and structural effects
Authors: Lewandowska Anna , Hug Gordon L. , Hörner Gerald , Pogocki Dariusz , Kazmierczak Franciszek , Marciniak Bronislaw
Published: March 2011

The rates and the mechanism of intramolecular hydrogen-atom transfer across the rigid diketopiperazine spacer in two epimeric benzophenone–tyrosine dyads were studied by nanosecond laser flash photolysis in 12 non-protic and protic solvents. Effects of the stereochemistry on the ground-state structures and conformational equilibria and dynamics have been addressed by means of NMR-based population analysis and long-term molecular-dynamics simulations. The excited triplet state of the benzophenone is found to be quenched intramolecularly by the remote phenol moiety with rates that are highly dependent on the solvent and on the relative benzophenone–phenol orientation. In agreement with previous studies, the kinetic diversity, with rates ranging from <105 s−1 to 2 × 107 s−1, can be attributed to retarding effects of the bulk viscosity and to effects of specific solvation, which can be both rate retarding and rate accelerating. As an extension of the previous knowledge, however, the phenomenology of the kinetic solvent effects, that is, the nature of the predominating solvent parameter and its absolute impact on the reactivity, is found to be highly correlated with structural effects.
Deposition of anionic conjugated poly(phenylenevinylene) onto silica nanoparticles via electrostatic interactions — Assembly and single-particle spectroscopy
Authors: Ngo An T. , Lau Kai L. , Quesnel Jeffrey S. , Aboukhalil Robert , Cosa Gonzalo
Published: March 2011

Fluorescent nanoparticles were prepared via adsorption of the conjugated polyelectrolyte poly[5-methoxy-2-(3-sulfopropoxy)-1,4-phenylenevinylene] (MPS-PPV) onto 50 and 100 nm aminosilane functionalized silica beads. The particles were investigated via ensemble and single-molecule or -particle spectroscopy techniques to quantify the effect of the silica bead core on the exciton migration efficiency within the polymer. Ensemble emission spectra and ensemble fluorescence quenching studies with methyl viologen are consistent with good exciton migration along the polymer in the polymer-coated bead. The silica nanobead scaffolding preserves the sensitivity of the free polymer and provides a controllable architecture that minimizes nonspecific interactions. Single-particle spectroscopy studies were conducted on particles immobilized onto the positively charged surface of glass cover slips. Particle immobilization enabled us to monitor the effect of oxygen scavenger solutions on individual particles by changing the surrounding solution. The intensity–time trajectories of individual beads provide a mechanism of signal transduction with potential applications in multiplexing studies. Hundreds of individual beads can be imaged in a rapid parallel fashion.
Effect of positively charged backbone groups on radical cation migration and reaction in duplex DNA
Authors: Kanvah Sriram , Schuster Gary B.
Published: March 2011

A series of DNA oligomers were prepared that contain guanidinium linkages (positively charged) positioned selectively in place of and among the normal negatively charged phosphodiester backbone groups of duplex DNA. One-electron oxidation of these DNA oligomers by UV irradiation of a covalently linked anthraquinone group generates a radical cation (electron “hole”) that migrates by hopping through the DNA and is trapped at reactive sites, GG steps, to form mutated bases that are detected by strand cleavage after subsequent piperidine treatment of the irradiated DNA. Analysis of the strand cleavage pattern reveals that guanidinium substitution in these oligomers does not measurably affect the charge migration rate but it does inhibit reaction at nearby guanines.
Regulation of L-type inward calcium channel activity by captopril and angiotensin II via the phosphatidyl inositol 3-kinase pathway in cardiomyocytes from volume-overload hypertrophied rat hearts
Authors: Alvin Zikiar , Laurence Graham G. , Coleman Bernell R , Zhao Aiqiu , Hajj-Moussa Majd , Haddad Georges E.
Published: March 2011

Heart failure can be caused by pro-hypertrophic humoral factors such as angiotensin II (Ang II), which regulates protein kinase activities. The intermingled responses of these kinases lead to the early compensated cardiac hypertrophy, but later to the uncompensated phase of heart failure. We have shown that although beneficial, cardiac hypertrophy is associated with modifications in ion channels that are mainly mediated through mitogen-activated protein (MAP) kinase and phosphatidylinositol 3-kinase (PI3K) activation. This study evaluates the control of L-type Ca2+current (ICa,L) by the Ang II/PI3K pathway in hypertrophied ventricular myocytes from volume-overload rats using the perforated patch-clamp technique. To assess activation of the ICa,Lin cardiomyocytes, voltages of 350 ms in 10 mV increments from a holding potential of –85 mV were applied to cardiocytes, with a pre-pulse to –45 mV for 300 ms. Volume overload-induced hypertrophy reduces ICa,L, whereas addition of Ang II alleviates the hypertrophic-induced decrease in a PI3K-dependent manner. Acute administration of Ang II (10−6 mol/L) to normal adult cardiomyocytes had no effect; however, captopril reduced their basal ICa,L. In parallel, captopril regressed the hypertrophy and inverted the Ang II effect on ICa,Lseemingly through a PI3K upstream effector. Thus, it seems that regression of cardiac hypertrophy by captopril improved ICa,Lpartly through PI3K.
Delivery of Common Lizards (Zootoca (Lacerta) vivipara) to nests of Eurasian Kestrels (Falco tinnunculus) determined by solar height and ambient temperature
Authors: Steen Ronny , Løw Line M. , Sonerud Geir A.
Published: March 2011

Recent development in video monitoring has allowed collecting of data on prey deliveries at raptor nests, and this offers an opportunity to relate prey selection to short-term changes in environmental factors on a scale of hours. Whereas raptors may specialize on ectothermic prey at southern latitudes, only some generalist raptors may include such prey in their diet at northern latitudes. In particular, at northern latitudes the activity pattern of ectothermic reptiles is strongly dependent on the prevailing weather conditions. To test whether this dependence affects the exposure of reptiles to raptors, we used video recording of prey deliveries at nests of the Eurasian Kestrel ( Falco tinnunculus L., 1758) at 61°N in Norway, where the Common Lizard ( Zootoca ( Lacerta ) vivipara (Jacquin, 1787)) is the only lizard available to kestrels. The probability that a prey item delivered at a kestrel nest was a lizard increased towards midday and also increased independently with increasing ambient temperature, which on average, was 20.2 °C when lizards were delivered compared with 15.7 °C when other types of prey were delivered. Thus, the delivery of lizards by kestrels in our study may be regarded as a functional response, where the abundance of lizards is determined by solar height and ambient temperature.
Reproductive success of male Atlantic spotted dolphins (Stenella frontalis) revealed by noninvasive genetic analysis of paternity
Authors: Green Michelle L. , Herzing Denise L. , Baldwin John D.
Published: March 2011

Cetaceans are known to frequently engage in sexual behavior; however, the lack of male parental investment in offspring makes assessment of male reproductive success difficult. We assessed paternity in a small population (mean individuals sighted per year = 93) of Atlantic spotted dolphins ( Stenella frontalis (G. Cuvier, 1829)) utilizing noninvasively collected fecal material. Samples (n = 88) were collected from dolphins from four social clusters. Of the 29 offspring tested, 34.5% were assigned paternity, resulting in 10 paternities assigned to seven males. Our study indicates that achieving a certain age is a potential precursor for males to mate successfully, as 18 years was the youngest estimated age of a male at the time of calf conception. In all pairings but one, the males were older than the female (mean age difference = 7.7+ years). Successful males were from two of the four social clusters and males most often mated within their social group or with females from the next geographically closest group. The study combines genetic data with known maternal pedigree information and reveals patterns in the overall mating system in a cetacean species where reproductive success of males was previously unknown.
Escape of parasitic water mites from dragonfly predators attacking their damselfly hosts
Authors: Nagel L. , Zanuttig M. , Forbes M. R.
Published: March 2011

Many parasites are transmitted trophically, whereas others can either succumb to, or escape from, the predators of their hosts. We examined the extent to which larval arrenurid water mites ( Arrenurus planus Marshall, 1908 and Arrenurus pollictus Marshall, 1910) parasitizing lestid damselflies ( Lestes forcipatus Rambur, 1842 and Lestes disjunctus Sélys, 1862) escape from predatory libellulid dragonflies that are consuming their hosts. We hypothesized that the brightly coloured mites would be avoided by feeding dragonflies. However, all partially engorged A. pollictus mites were eaten while their host was being consumed in staged predation trials. In contrast, half of the fully engorged mites detached and therefore escaped consumption. Trials with A. planus mites showed that they detached more readily than their congenerics, which may be due to selection on those temporary pond mites to survive desiccation stress following detachment. The effect of dragonfly predation on transitioning of mites from parasitic larvae to their free-living aquatic stages therefore depends on the degree of engorgement and the mite species.
SIGNATURE PAIRS FOR GROUP-INVARIANT HERMITIAN POLYNOMIALS
Authors: GRUNDMEIER DUSTY
Published: March 2011

We study the signature pair for certain group-invariant Hermitian polynomials arising in CR geometry. In particular, we determine the signature pair for the finite subgroups of SU(2). We introduce the asymptotic positivity ratio and compute it for cyclic subgroups of U(2). We calculate the signature pair for dihedral subgroups of U(2).
A MATRIX REALIZATION OF THE QUANTUM GROUP 𝔤p,q
Authors: ARIKE YUSUKE
Published: March 2011

In this paper we shall find a matrix realization of the quantum group 𝔤p,q introduced in [B. L. Feigin et al., Nucl. Phys. B757 (2006) 303–343]. For this purpose, we construct all primitive idempotents and a basis of 𝔤p,q. We determine the action of elements of the basis on indecomposable projective modules, that gives rise to a matrix realization of 𝔤p,q. By using this result, we obtain a basis of the space of symmetric linear functions on 𝔤p1,p2 and express the symmetric linear functions obtained by the left integral, the balancing element, and the center of 𝔤p,q in terms of this basis.
DENSITY FUNCTIONAL THEORY INVESTIGATE OF THE RgFn(Rg = Kr,Xe; n = 2,4,6) MOLECULES
Authors: FANG KAN , WU XUEBIN , DU CHENLEI , DAI YUNCHUAN , CHU SHIBIN , HU LEIBO , DENG JIANBO , FENG YUANPING
Published: March 2011

We present a systematic Density Functional Theory (DFT) calculations for the RgFn(Rg = Kr,Xe ; n = 2,4,6) molecules. The dissociation energies, harmonic vibrational frequencies and equilibrium bond lengths of these molecules are determined using several hybrid density functional methods. Results are compared with other theoretical studies and experimental values available. The accuracy of the DFT results is found to depend upon the functionals employed.
THERMOPOWER OF SnTe FROM BOLTZMANN TRANSPORT CALCULATIONS
Authors: SINGH DAVID J.
Published: March 2011

The doping and temperature dependent thermopower of SnTe is calculated from the first principles band structure using Boltzmann transport theory. We find that the p-type thermopower is inferior to PbTe consistent with experimental observations, but that the n-type thermopower is substantially more favorable.
MICROSTRUCTURE AND THERMOELECTRIC PROPERTIES OF (Zr,Hf)NiSn-BASED HALF-HEUSLER ALLOYS BY MELT SPINNING AND SPARK PLASMA SINTERING
Authors: YU CUI , ZHU TIEJUN , XIAO KAI , SHEN JUNJIE , ZHAO XINBING
Published: March 2011

(Zr,Hf)NiSn -based half-Heusler thermoelectric materials have been prepared by melt spinning and spark plasma sintering to refine the grain size. The grain sizes of the melt-spun thin ribbons varied from ~500 nm to ~3 μm and no significant grain growth were found for the bulk samples compacted by spark plasma sintering. Nanoscale precipitates dispersed in the matrix were observed, which should be more metallic due to the increase of the electrical conductivity. The reduction of lattice thermal conductivity was observed due to the refined grain sizes.
OPTICAL AND MAGNETO-OPTICAL ACTIVITY ON PARTIALLY SINTERED Y3Fe5O12 MATERIALS
Authors: FERNANDEZ-GARCIA LUCIA , SUAREZ MARTA , MENENDEZ JOSE LUIS
Published: March 2011

The optical and magneto-optical activities of yttrium iron garnet are shown to depend on the sintering stage. Low density yttrium iron garnet presents a lower optical activity than the high density garnet. The magneto-optical activity decreases at energies in which the optical transitions are associated to crystal field, indicating a relationship between the optical activity and the distortion of the structure. Finally, a calculation routine has been given to obtain the different elements of the dielectric tensor in bulk materials.
COMPOSITION DEPENDENCE OF BULK MODULUS AND BOND LENGTH OFMgxZn1-xO(x = 0.0-1.0) ALLOY SEMICONDUCTORS
Authors: LI KEYAN , DING ZHONGSHENG , XUE DONGFENG
Published: March 2011

For the first time, a general viewpoint of electronegativity and chemical bond in alloy semiconductors, e.g., MgxZn1-xO (x = 0.0-1.0) was proposed. The variation of bulk modulus and bond length, as well as their dependence on Mg concentration x were quantitatively simulated. The bulk moduli of MgxZn1-xO alloys decrease with increasing Mg concentration x. The detailed variation of bond lengths of both Mg–O and Zn–O in MgxZn1-xO alloys in the whole composition range was determined, which is less than 0.007 Å. The valence state of Mg is larger than that of Zn when x = 0.0-1.0, which leads to the increase of valence state of O with increasing Mg concentration x. The current results clearly indicate that MgxZn1-xO condenses in an alloy state.
LARGE-SCALE SYNTHESIS OF UNIFORM SILVER BROMIDE NANOWIRES USING ION TRACK MEMBRANE AS TEMPLATE
Authors: KUMAR SANJEEV , KUMAR VIJAY
Published: March 2011

Silver bromide (AgBr) nanowires were grown in the pores of ion track membrane. Simple chemical reaction technique was used where pores in the membrane act as reactors. Uniform morphology of nanowires was found using scanning electron microscopy (SEM). An X-ray diffraction (XRD) study shows the crystalline structure. Energy dispersive X-ray fluorescence (EDXRF) technique was used to study the composition of AgBr nanowires. Optical band gap of AgBr nanowires determined using absorption spectra was found to be higher than the bulk.
GROWTH OF ANTIMONY DOPED ZnO FIBER AND ITS APPLICATION IN DYE SENSITIZED SOLAR CELLS
Authors: GUO LEI , KERR LEI L.
Published: March 2011

Antimony doped ZnO (ZnO:Sb) fiber was grown by a simple thermal evaporation process of Zn powder and Sb2O3 . Scanning Electron Microscopy (SEM) shows that the grown fiber reaches more than 70 μm, which is the longest ZnO fiber reported in literature. Electron Backscattered Diffraction (EBSD) study indicates that this crystal is composed of three main phases: antimony doped zinc oxide (ZnO:Sb) , ordonezite (ZnSb2O6) and zinc antimony oxide (Zn7Sb2O12) . The current–voltage (I–V) characteristics demonstrate that the conversion efficiency of dye sensitized solar cell was greatly enhanced by ZnO:Sb fiber.
MICROSTRUCTURE AND ELECTRICAL PROPERTIES OF Pb(Zr0.65Ti0.35)O3 THIN FILMS GROWN ON OXIDE SUBSTRATES
Authors: LIU JINGSONG , LI HUIQIN , XU GUANGLIANG , CAO LINHONG
Published: March 2011

Pb(Zr0.65Ti0.35)O3 (PZT) thin films were deposited on SrRuO3 (SRO) buffer layer coated LaAlO3 (LAO) substrates by RF sputtering method. X-ray diffraction analyses indicate that the PZT thin films show epitaxial orientation and the in-plane epitaxial relationship between film and substrate is deduced as (001)[010] PZT ‖(001)[010] SRO ‖(001)[010] LAO . Despite the Zr -richcomposition, observations using transmission electron microscopy reveal that the PZT thin films exhibited tetragonal phase, which was due to the clamping effect of the substrates. The clamping effecton the electrical properties, especially on the dielectric properties, was evaluated. Ferroelectric measurements show that PZT films with LAO/SRO substrates were fatigue-free. However, the test of dielectric property dependences on temperature manifests a relatively low Curie temperature of the PZT films. The loss tangent decreasedwith increase intemperature. Owing to the release of clamping stress, the loss tangent decreased dramatically while the temperature was approaching the phase transition temperature of PZT thin films.
NHE3 modulates the severity of colitis in IL-10-deficient mice
Authors: Larmonier C. B. , Laubitz D. , Thurston R. D. , Bucknam A. L. , Hill F. M. , Midura-Kiela M. , Ramalingam R. , Kiela P. R. , Ghishan F. K.
Published: March 2011

NHE3, the major intestinal Na+/H+exchanger, was shown to be downregulated and/or inhibited in patients with inflammatory bowel disease (IBD), a phenomenon believed to contribute to inflammation-associated diarrhea. NHE3−/−mice spontaneously develop colitis and demonstrate high susceptibility to dextran sulfate-induced mucosal injury. We investigated the effects of NHE3 deficiency on the development of chronic colitis in an IL-10 knockout (KO) mouse model of Crohn's disease. NHE3−/−mice were first backcrossed to 129/SvEv mice for >10 generations, with no apparent changes in their survival or phenotype. These mice were crossed with IL-10−/−mice on the same genetic background, and the phenotypes of 10-wk-old wild-type (WT), IL-10−/−, NHE3−/−, and IL-10−/−/NHE3−/−(double-KO) mice were studied. Histological and immunohistochemical examination of the colon established important architectural alterations, including increased neutrophilic and mononuclear cell infiltration in double- compared with single-KO mice. Double-KO mice demonstrated increased colonic expression of neutrophil collagenase matrix metalloproteinase-8 and the chemokines macrophage inflammatory protein-2, CXCL1, CXCL10, and CXCL11. Colonic IFNγ, IL-17, and IL-12/23 p40 protein secretion was significantly increased in double- compared with single-KO mice. IL-10−/−/NHE3−/−mouse colonic epithelium exhibited increased hallmarks of apoptosis, including a significantly increased number of cleaved caspase-3-positive surface epithelial cells. These results highlight the importance of NHE3 in the maintenance of intestinal barrier integrity and in modulating the inflammatory process in IL-10-deficient mice. Chronic NHE3 inhibition or underexpression observed in IBD may therefore contribute to the pathogenesis of IBD by influencing the extent of the epithelial barrier defect and affect the ultimate degree of inflammation.
Longitudinal and transverse deformation of human Achilles tendon induced by isometric plantar flexion at different intensities
Authors: Iwanuma Soichiro , Akagi Ryota , Kurihara Toshiyuki , Ikegawa Shigeki , Kanehisa Hiroaki , Fukunaga Tetsuo , Kawakami Yasuo
Published: March 2011

The present study determined in vivo deformation of the entire Achilles tendon in the longitudinal and transverse directions during isometric plantar flexions. Twelve young women and men performed isometric plantar flexions at 0% (rest), 30%, and 60% of the maximal voluntary contraction (MVC) while a series of oblique longitudinal and cross-sectional magnetic resonance (MR) images of the Achilles tendon were taken. At the distal end of the soleus muscle belly, the Achilles tendon was divided into the aponeurotic (ATapo) and the tendinous (ATten) components. The length of each component was measured in the MR images. The widths of the Achilles tendon were determined at 10 regions along ATapo and at four regions along ATten. Longitudinal and transverse strains were calculated as changes in relative length and width compared with those at rest. The ATapo deformed in both longitudinal and transverse directions at 30%MVC and 60%MVC. There was no difference between the strains of the ATapo at 30%MVC and 60%MVC either in the longitudinal (1.1 and 1.6%) or transverse (5.0∼11.4 and 5.0∼13.9%) direction. The ATten was elongated longitudinally (3.3%) to a greater amount than ATapo, while narrowing transversely in the most distal region (−4.6%). The current results show that the magnitude and the direction of contraction-induced deformation of Achilles tendon are different for the proximal and distal components. This may be related to the different functions of Achilles tendon, i.e., force transmission or elastic energy storage during muscle contractions.
Pharmacometabonomic Profiling as a Predictor of Toxicity in Patients with Inoperable Colorectal Cancer Treated with Capecitabine
Authors: Backshall Alexandra , Sharma Rohini , Clarke Stephen J. , Keun Hector C.
Published: March 2011

Purpose: Endogenous metabolic profiles have been shown to predict the fate and toxicity of drugs such as acetaminophen in healthy individuals. However, the clinical utility of metabonomics in oncology remains to be defined. We aimed to evaluate the effect of pretreatment serum metabolic profiles generated by 1H NMR spectroscopy on toxicity in patients with inoperable colorectal cancer receiving single agent capecitabine.

Experimental Design: Serum was collected from 54 patients with a diagnosis of locally advanced or metastatic colorectal cancer prior to treatment with single agent capecitabine. 1H NMR spectroscopy was used to generate metabolic profile data for each patient. Toxicities were graded according to National Cancer Institute Common Toxicity Criteria version 2.0.

Results: Higher levels of low-density lipoprotein–derived lipids, including polyunsaturated fatty acids and choline phospholipids predicted for higher grade toxicity over the treatment period. Statistical analyses revealed a “pharmacometabonomic” lipid profile that correlated with severity of toxicity.

Conclusions: This study suggests that metabolic profiles can delineate subpopulations susceptible to adverse events and have a potential role in the assessment of treatment viability for cancer patients prior to commencing chemotherapy. Clin Cancer Res; 17(9); 3019–28. ©2011 AACR.
Adaptive Changes Result in Activation of Alternate Signaling Pathways and Acquisition of Resistance to Aromatase Inhibitors
Authors: Brodie Angela , Sabnis Gauri
Published: March 2011

Hormone therapy is an effective approach for the treatment of breast cancer. Although the antiestrogen tamoxifen has had a major impact on the treatment of the disease, aromatase inhibitors (AIs), which reduce estrogen synthesis, have recently proved to be more effective. These agents are now used as first-line therapy for postmenopausal breast cancer. Nevertheless, despite the efficacy of these agents, resistance to treatment eventually may occur in some patients. In an effort to overcome this resistance and extend the benefits of AIs, investigators have studied the mechanisms involved in resistance to AIs. Adaptive changes that result in activation of alternate signaling pathways in AI-resistant tumors have been identified in xenograft and cell line models. Expression of estrogen receptor α and aromatase was shown to be decreased in tumors after long-term treatment with AIs. In contrast, increased expression was observed in tyrosine kinase receptors such as Her-2 and insulin–like growth factor receptor, as well as in downstream signaling proteins such as mitogen–activated protein kinase. Functional activation of the mitogen–activated protein kinase pathway and dependency on growth factor receptor signaling have been observed in AI-resistant cells and tumors. Clin Cancer Res; 17(13); 4208–13. ©2011 AACR.
Phase I Clinical Trial Outcomes in 93 Patients with Brain Metastases: The MD Anderson Cancer Center Experience
Authors: Tsimberidou Apostolia Maria , Letourneau Katherine , Wen Sijin , Wheler Jennifer , Hong David , Naing Aung , Iskander Nancy G. , Uehara Cynthia , Kurzrock Razelle
Published: March 2011

Purpose: Patients with brain metastases are often excluded from clinical trials, but it is unclear whether they pose an enhanced risk.

Experimental Design: We reviewed the records of 1,181 consecutive patients, with and without brain metastases, treated in our Phase I Clinical Trials Program.

Results: Ninety-three patients had brain metastases at the time of referral. Their median age was 54 years; median follow-up, 8 months. The rates of stable disease ≥ 4 months, partial response, and complete response combined in patients with and without brain metastases were 17% and 27%, respectively (P = 0.03). Although the median survival of patients with brain metastases was shorter than that of patients without brain metastases (7.5 vs. 10.3 months; P = 0.002), in multivariate analysis, the presence of brain metastases was not an independent factor predicting survival. There was no difference in time-to-treatment failure (1.74 vs. 1.84 months, respectively; P = 0.61) or in grade 3 and 4 toxicity rates (including neurologic; 12% vs. 10%, respectively; P = 0.77) between patients with and without brain metastases.

Conclusions: The rates of survival and response of patients with brain metastases were lower than those for other patients in the phase I setting, but the presence of brain metastases was not an independent prognostic factor predicting survival, indicating that other covariates that coexist with brain metastases were more significant. Time-to-treatment failure for patients with brain metastases was not decreased, nor was the incidence of serious adverse effects (including neurologic toxicity) increased, suggesting that these patients should be eligible for early clinical trials. Clin Cancer Res; 17(12); 4110–8. ©2011 AACR.
Halothane-Anesthetized Rabbit: A New Experimental Model to Test the Effects of Besipirdine and Duloxetine on Lower Urinary Tract Function
Authors: Pérez-Martínez Francisco C. , Vela-Navarrete Remigio , Virseda Julio , Ocaña Ana V. , Lluel Philippe , Rekik Moèz , Bienaymé Hugues , Ferté Jacques , Attali Pierre , Palea Stefano
Published: March 2011

Introduction: The effects of besipirdine and its main metabolite, HP-748, as well as duloxetine and tomoxetine in the lower urinary tract (LUT) were studied using in vitro and in vivo techniques. Materials and Methods: For in vivo studies, besipirdine or duloxetine effects on cystometric parameters and striated sphincter electromyographic (SS-EMG) activity were investigated. On the isolated urethra, norepinephrine (NE) concentration-response curves (CRC) were performed in the presence of besipirdine, duloxetine or tomoxetine. Moreover, CRC to HP-748 were constructed in the absence or presence of prazosin. Potency (pEC50) and maximal responses (Emax) were determined. Results: Besipirdine at 1, 3 and 5 mg/kg intravenously (i.v.) induced a significant increase in SS-EMG activity (250, 273 and 241%, respectively), bladder capacity (172, 197, and 235%, respectively), intercontraction interval (ICI; 208, 242, and 400%, respectively), and residual volume (181, 191, and 236%, respectively). Duloxetine at 2 mg/kg i.v. increased significantly SS-EMG activity (219%), micturition volume (222%), and ICI (205%). In the isolated urethra, besipirdine, tomoxetine and duloxetine significantly displaced to the left the NE CRC. In addition, HP-748 induced contraction of the isolated urethra with a pEC50 of 5.89 and an Emax of 37%. Conclusions: These data support the potential of besipirdine as a new drug for LUT dysfunctions such as stress and mixed urinary incontinence.
Dural Metastases from Disseminated Prostate Cancer Clinically Mimicking a Benign Reactive Condition of the Dura: Case Report and Review of the Literature
Authors: Gunia S. , Ecke T. , Wohlfarth B. , Koch S. , Erbersdobler A.
Published: March 2011

Dural spread from prostate cancer (PC) is exceedingly uncommon. We report on a 62-year-old man suffering from disseminated PC with osseous metastases who presented with a parietal skull metastasis along with a circumscribed nodular thickening of the adjacent dura. Magnetic resonance imaging findings suggested a benign reactive condition of the dura which, however, histologically turned out to be a dural metastasis. Therefore, the present case report stresses the notion that very rarely, disseminated PC might present with clinically unsuspected dural metastases radiologically mimicking a benign condition.
Underestimated Risk of Bleeding after Male Transobturator Sling Procedure Caused by Early Re-Uptake of Anticoagulation
Authors: Kruck Stephan , Bedke Jens , Amend Bastian , Stenzl Arnulf , Sievert Karl-Dietrich
Published: March 2011

The management of postoperative male stress urinary incontinence (SUI) is changing rapidly as greater emphasis on minimizing invasiveness and reducing complications leads to technical innovations. Various studies have reported comparable continence but lower complication rates for male urethral slings than those observed with artificial urinary sphincters. For this reason, the transobturator sling procedure has been considered a safe and effective treatment option in male SUI patients. In this case study we report severe bleeding with a large hematoma that required transfusion after implantation of an AdVance® male transobturator polypropylene sling in an early re-anticoagulated patient.
Imaging of Renal Cell Carcinoma: State of the Art and Recent Advances
Authors: Sacco Emilio , Pinto Francesco , Totaro Angelo , D’Addessi Alessandro , Racioppi Marco , Gulino Gaetano , Volpe Andrea , Marangi Francesco , D’Agostino Daniele , Bassi Pierfrancesco
Published: March 2011

Background and Aim: Renal cell carcinoma (RCC) is the 13th most common cancer worldwide and accounts for 4% of all adult malignancies. Herein the state of the art and recent advances in cross-sectional radiological imaging applied to RCC are reviewed, including ultrasonography, computed tomography, magnetic resonance imaging, and positron emission tomography. Methods: Literature search of peer-reviewed papers published by October 2010. Results: In front of more conventional and widespread imaging tools, such as ultrasonography and computed tomography, an array of newer and attractive radiological modalities are under investigation and show promise to improve our ability to noninvasively detect renal tumors and its recurrences, accurately assess the extent of the disease, and reliably evaluate treatment response, particularly in the era of antiangiogenetic therapy. Conclusions: Recent major advances in radiological imaging techniques have considerably improved our ability to diagnose, stage and follow-up RCC. Further studies are needed to evaluate the potential of most recent and still investigational imaging tools.