bluuebunny/crossref_metadata_2025 huggingface dataset:
Sexuell übertragbare Infektionen – anorektale Manifestationen
Authors: Lautenschlager Stephan
Published: June 2013

Seit über 10 Jahren sind wir in der Schweiz mit steigenden Zahlen von Geschlechtskrankheiten konfrontiert. Zahlreiche Erreger können neben genitalen auch anorektale Veränderungen verursachen. Während es sich hierbei gelegentlich um eine Ausbreitung der Infektion per contingentatem handelt, findet überwiegend eine direkte Inokulation nach rezeptivem Analverkehr häufig bei homosexuellen Männern aber auch bei Frauen statt. Perianal und teilweise endoanal ist die klinische Präsentation von Geschlechtskrankheiten wie Syphilis, Herpes, Kondylome oder Ulcus molle vergleichbar mit derjenigen in der Genitalregion. Bei Patienten mit Proktitis findet sich bei zahlreichen Erregern eine ähnliche Symptomatik in variierender Intensität, weshalb der Erregeridentifikation im Labor eine große Bedeutung zukommt. Neben einer Sexualanamnese ist eine Untersuchung der Analregion unter Zuhilfenahme eines Proktoskopes, Abstrichen für PCR und Kultur sowie serologischen und allenfalls histologischen Abklärungen für eine korrekte Diagnose von STI unabdingbar.
The Role of Vitamins in Aging Societies
Authors: Troesch Barbara , Eggersdorfer Manfred , Weber Peter
Published: June 2013

Raising numbers of elderly lead to a dramatic shift in demographics, accompanied by an increase in non-communicable diseases such as cancer, cardiovascular disease and dementia. All these conditions are thought to be modifiable by diet to some degree and mounting evidence indicates that improved intakes of certain vitamins can slow their progress. Strong evidence exists for the beneficial effect of vitamin D on the risk of bone fractures. Moreover, as chromosomal damage is a risk factor for dementia, supplementation with nutrients preventing these impairments are thought to have a beneficial effect on cognitive decline. However, the aging progress strongly affects nutrient intakes and utilisation due to social, physical and psychological changes. Data from dietary surveys suggest that many of the elderly in Europe have intakes for various vitamins that are well below the recommendations. The situation appears to be even more critical for elderly in institutions such as care homes. Given the increasing number of elderly and the importance of an adequate supply with vitamins, more research is warranted to find nutritional solutions to improve their wellbeing and health - which in the long run can be expected to contribute to reduce the ever increasing health care costs.
Zinc co-ordination by the DHHC cysteine-rich domain of the palmitoyltransferase Swf1
Authors: González Montoro Ayelén , Quiroga Rodrigo , Valdez Taubas Javier
Published: June 2013

S-acylation, commonly known as palmitoylation, is a widespread post-translational modification of proteins that consists of the thioesterification of one or more cysteine residues with fatty acids. This modification is catalysed by a family of PATs (palmitoyltransferases), characterized by the presence of a 50-residue long DHHC-CRD (Asp-His-His-Cys cysteine-rich domain). To gain knowledge on the structure–function relationships of these proteins, we carried out a random-mutagenesis assay designed to uncover essential amino acids in Swf1, the yeast PAT responsible for the palmitoylation of SNARE (soluble N-ethylmaleimide-sensitive fusion protein-attachment protein receptor) proteins. We identified 21 novel loss-of-function mutations, which are mostly localized within the DHHC-CRD. Modelling of the tertiary structure of the Swf1 DHHC domain suggests that it could fold as a zinc-finger domain, co-ordinating two zinc atoms in a CCHC arrangement. All residues predicted to be involved in the co-ordination of zinc were found to be essential for Swf1 function in the screen. Moreover, these mutations result in unstable proteins, in agreement with a structural role for these zinc fingers. The conservation of amino acids predicted to form each zinc-binding pocket suggests a shared function, as the selective pressure to maintain them is lost upon mutation of one of them. A Swf1 orthologue that lacks one of the zinc-binding pockets is able to complement a yeast swf1∆ strain, possibly because a similar fold can be stabilized by hydrogen bonds instead of zinc co-ordination. Finally, we show directly that recombinant Swf1 DHHC-CRD is able to bind zinc. Sequence analyses of DHHC domains allowed us to present models of the zinc-binding properties for all PATs.
Dialectal Effects on a Clinical Spanish Word Recognition Test
Authors: Shi Lu-Feng , Canizales Luz Adriana
Published: June 2013

Purpose

American Spanish dialects have substantial phonetic and lexical differences. This study investigated how dialectal differences affect Spanish/English bilingual individuals' performance on a clinical Spanish word recognition test.

Method

Forty Spanish/English bilinguals participated in the study—20 dominant in Spanish and 20 in English. Within each group, 10 listeners spoke the Highland dialect, and 10 spoke the Caribbean/Coastal dialect. Participants were maximally matched between the 2 dialectal groups regarding their demographic and linguistic background. Listeners were randomly presented 4 lists of Auditec Spanish bisyllabic words at 40 dB SL re: pure-tone average. Each list was randomly assigned with a signal-to-noise ratio (SNR) of quiet, +6, +3, and 0 dB, in the presence of speech-spectrum noise. Listeners responded orally and in writing.

Results

Dialect and language dominance both significantly affected listener performance on the word recognition test. Higher performance levels were obtained with Highland than Caribbean/Coastal listeners and with Spanish-dominant than English-dominant listeners. The dialectal difference was particularly evident in favorable listening conditions (i.e., quiet and +6 dB SNR) and could not be explained by listeners' familiarity with the test words.

Conclusion

Dialects significantly affect the clinical assessment of Spanish-speaking clients' word recognition. Clinicians are advised to consider the phonetic features of the dialect when scoring a client's performance.
Autoimmune Inner Ear Disease Preliminary Case Report: Audiometric Findings Following Steroid Treatments
Authors: Harris Dave A. , Mikulec Anthony A. , Carls Sarah L.
Published: June 2013

Purpose

This study examined the audiometric findings following steroid treatment for autoimmune inner ear disease (AIED), which is characterized by bilateral subacute hearing loss, using oral and intratympanic treatment.

Method

The charts of 9 patients with AIED who had been seen in the Saint Louis University School of Medicine's clinic between 2004 and 2011 were reviewed, with special focus on audiometric results.

Results

The majority of patients benefited from treatment for AIED. Four patients (6 ears) received intratympanic therapy as part of their treatment.

Conclusion

Patients with AIED appeared to benefit from a clinical pathway using a prolonged course of oral steroids, followed by a trial of intratympanic steroids and/or immunosuppresants for refractory cases.
Using the Speech Understanding in Noise (SUN) Test for Adult Hearing Screening1
Authors: Paglialonga Alessia , Grandori Ferdinando , Tognola Gabriella
Published: June 2013

Purpose

To develop a novel speech-in-noise test for adult hearing screening—the Speech Understanding in Noise (SUN) test. The goal was to design a fast, automated, easy-to-use test to identify difficulties in speech communication.

Method

The SUN test consists of a short list of intervocalic consonants in noise presented in a forced-choice paradigm by means of a touch screen. The SUN test was developed and evaluated in an overall population of >6,000 participants. The test is available in various languages (i.e., English, French, German, and Italian) and continues to be developed in others (e.g., Spanish, Portuguese, and Mandarin).

Results

Test time was <1 min/ear. Test–retest reliability was very good. The test showed good agreement with conventional clinical measures (e.g., pure-tone testing, speech-in-noise testing, and self-reported hearing handicap). The test's sensitivity and specificity to identify disabling hearing impairment were 84% and 75%, respectively. The same results were obtained in low and high ambient noise.

Conclusion

The SUN test is fast, repeatable, easy to use, self-explanatory, specific to the impairment, and robust to ambient noise. It may be a viable approach for adult hearing screening in clinical as well as nonclinical settings.
Effect of Tinnitus on Distortion Product Otoacoustic Emissions Varies With Hearing Loss
Authors: Husain Fatima T.
Published: June 2013

Purpose

The aim of this study was to measure the effect of tinnitus, while accounting for the effect of hearing loss and aging, on distortion product otoacoustic emissions (DPOAEs).

Method

DPOAEs were measured twice in both ears in 5 groups of participants: young adults with normal hearing, middle-age adults with normal hearing, adults with high-frequency sensorineural hearing loss, age-matched adults with similar hearing loss and tinnitus, and adults with normal hearing and chronic tinnitus.

Results

Multivariate analysis revealed a main effect of hearing loss and age, but no effect of tinnitus, across all 5 groups. Separate tests revealed significant effects of age and tinnitus in the normal-hearing groups and hearing loss in adults with or without tinnitus, but no effect of tinnitus in those with hearing loss.

Conclusion

DPOAE levels in the group of adults with hearing loss and tinnitus were diminished, but those in the group with normal hearing and tinnitus were enhanced, relative to DPOAE levels in the controls. Outer hair cell function, as indexed by DPOAEs, exhibits a complex association with tinnitus, and this has implications in the use of DPOAEs as a tool both for testing for tinnitus presence and for creating a model of neural mechanisms underlying tinnitus.
Masking Release and Modulation Interference in Cochlear Implant and Simulation Listeners
Authors: Jin Su-Hyun , Nie Yingjiu , Nelson Peggy
Published: June 2013

Purpose

To examine the effects of temporal and spectral interference of masking noise on sentence recognition for listeners with cochlear implants (CI) and normal-hearing persons listening to vocoded signals that simulate signals processed through a CI (NH-Sim).

Method

NH-Sim and CI listeners participated in the experiments using speech and noise that were processed by bandpass filters. Depending on the experimental condition, the spectra of the maskers relative to that of speech were set to be completely embedded with, partially overlapping, or completely separate from, the speech. The maskers were either steady or amplitude modulated and were presented at +10 dB signal-to-noise ratio.

Results

NH-Sim listeners experienced progressively more masking as the masker became more spectrally overlapping with speech, whereas CI listeners experienced masking even when the masker was spectrally remote from the speech signal. Both the NH-Sim and CI listeners experienced significant modulation interference when noise was modulated at a syllabic rate (4 Hz), suggesting that listeners may experience both modulation interference and masking release. Thus, modulated noise has mixed and counteracting effects on speech perception.

Conclusion

When the NH-Sim and CI listeners with poor spectral resolution were tested using syllabic-like rates of modulated noise, they tended to integrate or confuse the noise with the speech, causing an increase in speech errors. Optional training programs might be useful for CI listeners who show more difficulty understanding speech in noise.
Employing green synthesized silver nanoparticles as light harvesters in nanostructured solar cells
Authors: Rajendra Prasad M. B. , Deena S. , Rajesh Ch. , Pandit Vishal K. , Pathan Habib M.
Published: June 2013

Surface plasmon resonance associated with metallic nanoparticles is an optical phenomenon which can be exploited to improve light harvesting in solar cells. Silver (Ag) nanoparticles (NPs) have attracted attention for solar cell application these days, due to their better light harvesting abilities in the visible range. The quantum dot sensitized solar cells (QDSSCs) are one of the third generation photoelectro chemical solar cells which hold a promise of 44% theoretically but practically achieved 5% photovoltaic efficiency till date. The present work focuses on the use of Ag NPs prepared from a facile green synthesis in improving the efficiency of QDSSC. Ag NPs prepared here use banana sap for reducing the Ag ions. Cadmium sulphide quantum dots sensitized titania (CdS-TiO2) porous photo anode is coated with Ag NPs and solar cell is fabricated with graphite as the counter electrode and polysulfide as electrolyte. Optical absorption studies of photo anode are performed and basic photovoltaic measurements are conducted to evaluate the influence of Ag NPs on the cell performance.
Dynamical modeling and analysis of large cellular regulatory networks
Authors: Bérenguier D. , Chaouiya C. , Monteiro P. T. , Naldi A. , Remy E. , Thieffry D. , Tichit L.
Published: June 2013

The dynamical analysis of large biological regulatory networks requires the development of scalable methods for mathematical modeling. Following the approach initially introduced by Thomas, we formalize the interactions between the components of a network in terms of discrete variables, functions, and parameters. Model simulations result in directed graphs, called state transition graphs. We are particularly interested in reachability properties and asymptotic behaviors, which correspond to terminal strongly connected components (or "attractors") in the state transition graph. A well-known problem is the exponential increase of the size of state transition graphs with the number of network components, in particular when using the biologically realistic asynchronous updating assumption. To address this problem, we have developed several complementary methods enabling the analysis of the behavior of large and complex logical models: (i) the definition of transition priority classes to simplify the dynamics; (ii) a model reduction method preserving essential dynamical properties, (iii) a novel algorithm to compact state transition graphs and directly generate compressed representations, emphasizing relevant transient and asymptotic dynamical properties. The power of an approach combining these different methods is demonstrated by applying them to a recent multilevel logical model for the network controlling CD4+ T helper cell response to antigen presentation and to a dozen cytokines. This model accounts for the differentiation of canonical Th1 and Th2 lymphocytes, as well as of inflammatory Th17 and regulatory T cells, along with many hybrid subtypes. All these methods have been implemented into the software GINsim, which enables the definition, the analysis, and the simulation of logical regulatory graphs.
Polarization of molecular angular momentum in the chemical reactions Li + HF and F + HD
Authors: Krasilnikov Mikhail B. , Popov Ruslan S. , Roncero Octavio , De Fazio Dario , Cavalli Simonetta , Aquilanti Vincenzo , Vasyutinskii Oleg S.
Published: June 2013

The quantum mechanical approach to vector correlation of angular momentum orientation and alignment in chemical reactions [G. Balint-Kurti and O. S. Vasyutinskii, J. Phys. Chem. A 113, 14281 (2009)]10.1021/jp902796v is applied to the molecular reagents and products of the Li + HF [L. Gonzalez-Sanchez, O. S. Vasyutinskii, A. Zanchet, C. Sanz-Sanz, and O. Roncero, Phys. Chem. Chem. Phys. 13, 13656 (2011)]10.1039/c0cp02452j and F + HD [D. De Fazio, J. Lucas, V. Aquilanti, and S. Cavalli, Phys. Chem. Chem. Phys. 13, 8571 (2011)]10.1039/c0cp02738c reactions for which accurate scattering information has become recently available through time-dependent and time-independent approaches. Application of the theory to two important particular cases of the reactive collisions has been considered: (i) the influence of the angular momentum polarization of reactants in the entrance channel on the spatial distribution of the products in the exit channel and (ii) angular momentum polarization of the products of the reaction between unpolarized reactants. In the former case, the role of the angular momentum alignment of the reactants is shown to be large, particularly when the angular momentum is perpendicular to the reaction scattering plane. In the latter case, the orientation and alignment of the product angular momentum was found to be significant and strongly dependent on the scattering angle. The calculation also reveals significant differences between the vector correlation properties of the two reactions under study which are due to difference in the reaction mechanisms. In the case of F + HD reaction, the branching ratio between HF and DF production points out interest in the insight gained into the detailed dynamics, when information is available either from exact quantum mechanical calculations or from especially designed experiments. Also, the geometrical arrangement for the experimental determination of the product angular momentum orientation and alignment based on a compact and convenient spherical tensor expression for the intensity of the resonance enhanced multiphoton ionization (REMPI 2 + 1) signal is suggested.
Atomistic simulation of structure and dynamics of the plastic crystal diethyl(methyl)(isobutyl)phosphonium hexafluorophosphate
Authors: Chen F. , Jin L. , de Leeuw S. W. , Pringle J. M. , Forsyth M.
Published: June 2013

Molecular dynamics simulations have been performed to investigate the interrelations between structures, transport mechanisms, and phase transitions of an organic ionic plastic crystal material, diethyl(methyl)(isobutyl)phosphonium hexafluorophosphate ([P1,2,2,4][PF6]), in both solid and liquid phases. Examination of the temperature dependence of supercell parameters and radial distribution functions provides evidence of plastic phase transitions. Nonlinear increments of cell size within the temperature range 123–413 K are consistent with the plastic phase transitions identified from experimental analysis. The time- and temperature-dependent microstructure and dynamics have been intensively studied through analysis of trajectory files. The rotational motion and diffusion of the matrix ions are quantitatively analysed via rotational correlation functions and mean square displacements. We present new information on the evolution of molecular motions in different phases, and compare and contrast our findings with previously reported hypotheses based on nuclear magnetic resonance results. This work provides valuable information at an atomistic level to explain the experimental observations, which helps further understanding of the molecular motions underlying the plastic phase transitions.
Effect of molecular-orbital rotations on ground-state energies in the parametric two-electron reduced density matrix method
Authors: Sand Andrew M. , Mazziotti David A.
Published: June 2013

Different sets of molecular orbitals and the rotations connecting them are of great significance in molecular electronic structure. Most electron correlation methods depend on a reference wave function that separates the orbitals into occupied and unoccupied spaces. Energies and properties from these methods depend upon rotations between the spaces. Some electronic structure methods, such as modified coupled electron pair approximations and the recently developed parametric two-electron reduced density matrix (2-RDM) methods [D. A. Mazziotti, Phys. Rev. Lett. 101, 253002 (2008)]10.1103/PhysRevLett.101.253002, also depend upon rotations between occupied orbitals and rotations between unoccupied orbitals. In this paper, we explore the sensitivity of the ground-state energies from the parametric 2-RDM method to rotations within the occupied space and within the unoccupied space. We discuss the theoretical origin of the rotational dependence and provide computational examples at both equilibrium and non-equilibrium geometries. We also study the effect of these rotations on the size extensivity of the parametric 2-RDM method. Computations show that the orbital rotations have a small effect upon the parametric 2-RDM energies in comparison to the energy differences observed between methodologies such as coupled cluster and parametric 2-RDM. Furthermore, while the 2-RDM method is rigorously size extensive in a local molecular orbital basis set, calculations reveal negligible deviations in nonlocal molecular orbital basis sets such as those from canonical Hartree-Fock calculations.
Using Bayesian analysis and Gaussian processes to infer electron temperature and density profiles on the Mega-Ampere Spherical Tokamak experiment
Authors: von Nessi G. T. , Hole M. J.
Published: June 2013

A unified, Bayesian inference of midplane electron temperature and density profiles using both Thomson scattering (TS) and interferometric data is presented. Beyond the Bayesian nature of the analysis, novel features of the inference are the use of a Gaussian process prior to infer a mollification length-scale of inferred profiles and the use of Gauss-Laguerre quadratures to directly calculate the depolarisation term associated with the TS forward model. Results are presented from an application of the method to data from the high resolution TS system on the Mega-Ampere Spherical Tokamak, along with a comparison to profiles coming from the standard analysis carried out on that system.
Lateral heat diffusion investigation of a layered structure: Application to the complete thermal characterization of a lithium phosphorous oxynitride film
Authors: Xu F. , Frétigny C. , Fournier D. , Belliard L. , Vincent S. , Perrin B. , Martin S. , Secouard C. , Duquesne J.-Y.
Published: June 2013

We present a new method to measure without any calibration the thermal effusivity, conductivity, and diffusivity of an insulating layer deposited on a substrate, using lateral heat diffusion. The method is applied to Lithium phosphorous oxynitride, a thin film solid-state electrolyte used in micro-batteries.
Quantum interference and control of the dynamic Franz-Keldysh effect: Generation and detection of terahertz space-charge fields
Authors: Wang Rui , Jacobs Paul , Zhao Hui , Smirl Arthur L.
Published: June 2013

The Dynamic Franz Keldysh Effect (DFKE) is produced and controlled in bulk gallium arsenide by quantum interference without the aid of externally applied fields and is spatially and temporally resolved using ellipsometric pump-probe techniques. The ∼3 THz internal driving field for the DFKE is a transient space-charge field that is associated with a critically damped coherent plasma oscillation produced by oppositely traveling ballistic electron and hole currents that are injected by two-color quantum interference techniques. The relative phase and polarization of the two pump pulses can be used to control the DFKE.
Note: A novel dual-channel time-of-flight mass spectrometer for photoelectron imaging spectroscopy
Authors: Qin Zhengbo , Wu Xia , Tang Zichao
Published: June 2013

A novel dual-channel time-of-flight mass spectrometer (D-TOFMS) has been designed to select anions in the photoelectron imaging measurements. In this instrument, the radiation laser can be triggered precisely to overlap with the selected ion cloud at the first-order space focusing plane. Compared with that of the conventional single channel TOFMS, the in situ mass selection performance of D-TOFMS is significantly improved. Preliminary experiment results are presented for the mass-selected photodetachment spectrum of F− to demonstrate the capability of the instrument.
Influence of catalyst droplet diameter on the growth direction of InP nanowires grown on Si(001) substrate
Authors: Naji K. , Saint-Girons G. , Penuelas J. , Patriarche G. , Largeau L. , Dumont H. , Rojo-Romeo P. , Gendry M.
Published: June 2013

It is demonstrated that the growth direction of InP nanowires grown on (001)-oriented silicon substrate strongly depends on the diameter of the gold catalyst droplets. Small droplets with diameter less than about 15 nm lead to the formation of nanowires leaning on the {111} planes of the zinc blende InP seeds formed in the early stages of growth. Larger droplets lead to the formation of twins in the InP seeds and to the formation of nanowires leaning on the {111} planes of these twinned InP variants, inducing growth directions corresponding to the 〈115〉 directions of the silicon substrate.
Pyrolysis kinetics of de-oiled cakes by thermogravimetric analysis
Authors: Volli Vikranth , Singh R. K.
Published: June 2013

De-oiled cakes could be a potential source of renewable energy that can supply liquid and gaseous fuels through thermo-chemical conversion processes. Thermal properties and reaction kinetics of de-oiled cakes play prominent role in design, operation, and modeling of these systems. In the present work, thermogravimetric analysis (TGA) and derivative thermogravimetry (DTG) techniques were used to study the thermo-chemical behavior of four varieties of de-oiled cakes (sesame, mustard, neem, and mahua). The thermal degradation was studied in an inert (N2) atmosphere from ambient temperature to 700 °C using heating rates of 10, 20, 30, 50, 100 °C min−1. The structure, chemical composition, and thermal properties were investigated by using Fourier Transform Infrared spectroscopy, differential scanning calorimetry (DSC), and XRD. The activation energy and pre-exponential factor based on Arrhenius equation were determined by using Coats and Redfern Integral method from the TGA data.
Note: A latched comparator circuit for triggering continuous-wave cavity ring-down spectroscopy
Authors: Rasheed Abdur , Curtis Daniel B.
Published: June 2013

Continuous-wave cavity ring-down spectroscopy offers several advantages over cavity ring-down spectroscopy with a pulsed laser, such as a higher repetition rate and decreased cost. However, the continuous-wave technique requires a more complicated experimental setup because the laser must be switched off rapidly when the intensity is high in order to observe a ring-down event. This note describes an inexpensive and simple latched comparator circuit that can be used to detect light intensity above a threshold value and send a signal to rapidly steer the beam out of the cavity and initiate a ring-down event. The latch eliminates switching noise by preventing the comparator from switching during the ring-down event.
Poly [1,1'-bis(ethynyl)-4,4'-biphenyl(bis-tributylphosphine)Pt(II)] solutions used as low dose ionizing radiation dosimeter
Authors: Bronze-Uhle E. S. , Batagin-Neto A. , Fernandes D. M. , Fratoddi I. , Russo M. V. , Graeff C. F. O.
Published: June 2013

In this work, the effect of gamma radiation on the optical properties of polymetallayne poly[1,1'-bis(ethynyl)-4,4'-biphenyl(bis-tributylphosphine)Pt(II)] (Pt-DEBP) in chloroform solution is studied. The samples were irradiated at room temperature with doses from 0.01 Gy to 1 Gy using a 60Co gamma ray source. A new band at 420 nm is observed in the emission spectra, in superposition to the emission maximum at 398 nm, linearly dependent on dose. We propose to use the ratio of the emission amplitude bands as the dosimetric parameter. This method proved to be robust, accurate, and can be used as a dosimeter in medical applications.
Simulation of linear and nonlinear Landau damping of lower hybrid waves
Authors: Qi Lei , Wang X. Y. , Lin Y.
Published: June 2013

The linear physics of lower hybrid waves (LHWs) and their nonlinear interaction with particles through Landau damping are studied with the gyrokinetic electron and fully kinetic ion (GeFi) particle simulation model in the electrostatic limit. Unlike most other wave modes, the LHWs can resonantly interact with both electrons and ions, with the former being highly magnetized and latter nearly unmagnetized around the lower hybrid frequency. Direct interactions of LHWs with electrons and/or ions are investigated for cases with various k∥/k,Ti/Te, and wave amplitudes. In the linear electron Landau damping (ELD), the dispersion relation and the linear damping rate obtained from our simulation agree well with the analytical linear theory. As the wave amplitude increases, the nonlinear Landau effects are present, and a transition from strong decay at smaller amplitudes to weak decay at larger amplitudes is observed. In the nonlinear stage, the LHWs in the long time evolution finally exhibit a steady Bernstein-Greene-Kruskal mode, in which the wave amplitude is saturated above the noise level. While the resonant electrons are trapped in the wave field in the nonlinear ELD, the resonant ions are untrapped in the LHW time scales. The ion Landau damping is thus predominantly in a linear fashion, leading to a wave saturation level significantly lower than that in the ELD. On the long time scales, however, the ions are still weakly trapped. The results show a coupling between the LHW frequency and the ion cyclotron frequency during the long-time LHW evolution.
Terahertz beam steering by optical coherent control
Authors: Füser Heiko , Bieler Mark
Published: June 2013

We demonstrate optical coherent control of the emission direction of THz radiation. Femtosecond laser pulses are used to excite different types of ultrafast photocurrents along different directions in a bulk GaAs sample. The overall emission pattern can be modified by changing the phase of the optical excitation. With this method, THz beam steering of about 8° is realized. A simple dipole-based model allows us to relate the size of the steering effect to the amplitude ratio between the different photocurrent contributions and to diffraction effects resulting from the excitation spot size.
Use of anion–aromatic interactions to position the general base in the ketosteroid isomerase active site
Authors: Schwans Jason P. , Sunden Fanny , Lassila Jonathan K. , Gonzalez Ana , Tsai Yingssu , Herschlag Daniel
Published: June 2013

Although the cation–pi pair, formed between a side chain or substrate cation and the negative electrostatic potential of a pi system on the face of an aromatic ring, has been widely discussed and has been shown to be important in protein structure and protein–ligand interactions, there has been little discussion of the potential structural and functional importance in proteins of the related anion–aromatic pair (i.e., interaction of a negatively charged group with the positive electrostatic potential on the ring edge of an aromatic group). We posited, based on prior structural information, that anion–aromatic interactions between the anionic Asp general base and Phe54 and Phe116 might be used instead of a hydrogen-bond network to position the general base in the active site of ketosteroid isomerase from
Comamonas testosteroni
as there are no neighboring hydrogen-bonding groups. We have tested the role of the Phe residues using site-directed mutagenesis, double-mutant cycles, and high-resolution X-ray crystallography. These results indicate a catalytic role of these Phe residues. Extensive analysis of the Protein Data Bank provides strong support for a catalytic role of these and other Phe residues in providing anion–aromatic interactions that position anionic general bases within enzyme active sites. Our results further reveal a potential selective advantage of Phe in certain situations, relative to more traditional hydrogen-bonding groups, because it can simultaneously aid in the binding of hydrophobic substrates and positioning of a neighboring general base.
Interannual variation of water isotopologues at Vostok indicates a contribution from stratospheric water vapor
Authors: Winkler Renato , Landais Amaelle , Risi Camille , Baroni Melanie , Ekaykin Alexey , Jouzel Jean , Petit Jean Robert , Prie Frederic , Minster Benedicte , Falourd Sonia
Published: June 2013

Combined measurements of water isotopologues of a snow pit at Vostok over the past 60 y reveal a unique signature that cannot be explained only by climatic features as usually done. Comparisons of the data using a general circulation model and a simpler isotopic distillation model reveal a stratospheric signature in the17O-excess record at Vostok. Our data and theoretical considerations indicate that mass-independent fractionation imprints the isotopic signature of stratospheric water vapor, which may allow for a distinction between stratospheric and tropospheric influences at remote East Antarctic sites.
Probing the transient dark state of substrate binding to GroEL by relaxation-based solution NMR
Authors: Libich David S. , Fawzi Nicolas L. , Ying Jinfa , Clore G. Marius
Published: June 2013

The mechanism whereby the prototypical chaperonin GroEL performs work on substrate proteins has not yet been fully elucidated, hindered by lack of detailed structural and dynamic information on the bound substrate. Previous investigations have produced conflicting reports on the state of GroEL-bound polypeptides, largely due to the transient and dynamic nature of these complexes. Here, we present a unique approach, based on combined analysis of four complementary relaxation-based NMR experiments, to probe directly the “dark” NMR-invisible state of the model, intrinsically disordered, polypeptide amyloid β (Aβ40) bound to GroEL. The four NMR experiments, lifetime line-broadening, dark-state exchange saturation transfer, relaxation dispersion, and small exchange-induced chemical shifts, are dependent in different ways on the overall exchange rates and populations of the free and bound states of the substrate, as well as on residue-specific dynamics and structure within the bound state as reported by transverse magnetization relaxation rates and backbone chemical shifts, respectively. Global fitting of all the NMR data shows that the complex is transient with a lifetime of <1 ms, that binding involves two predominantly hydrophobic segments corresponding to predicted GroEL consensus binding sequences, and that the structure of the bound polypeptide remains intrinsically and dynamically disordered with minimal changes in secondary structure propensity relative to the free state. Our results establish a unique method to observe NMR-invisible dynamic states of GroEL-bound substrates and to describe at atomic resolution the events between substrate binding and encapsulation that are crucial for understanding the normal and stress-related metabolic function of chaperonins.
S-nitrosylation therapy to improve oxygen delivery of banked blood
Authors: Reynolds James D. , Bennett Kyla M. , Cina Anthony J. , Diesen Diana L. , Henderson Matthew B. , Matto Faisal , Plante Andrew , Williamson Rachel A. , Zandinejad Keivan , Demchenko Ivan T. , Hess Douglas T. , Piantadosi Claude A. , Stamler Jonathan S.
Published: June 2013

From the perspectives of disease transmission and sterility maintenance, the world’s blood supplies are generally safe. However, in multiple clinical settings, red blood cell (RBC) transfusions are associated with adverse cardiovascular events and multiorgan injury. Because ∼85 million units of blood are administered worldwide each year, transfusion-related morbidity and mortality is a major public health concern. Blood undergoes multiple biochemical changes during storage, but the relevance of these changes to unfavorable outcomes is unclear. Banked blood shows reduced levels of S-nitrosohemoglobin (SNO-Hb), which in turn impairs the ability of stored RBCs to effect hypoxic vasodilation. We therefore reasoned that transfusion of SNO-Hb–deficient blood may exacerbate, rather than correct, impairments in tissue oxygenation, and that restoration of SNO-Hb levels would improve transfusion efficacy. Notably in mice, administration of banked RBCs decreased skeletal muscle pO
2
, but infusion of renitrosylated cells maintained tissue oxygenation. In rats, hemorrhage-induced reductions in muscle pO
2
were corrected by SNO-Hb–repleted RBCs, but not by control, stored RBCs. In anemic awake sheep, stored renitrosylated, but not control RBCs, produced sustained improvements in O
2
delivery; in anesthetized sheep, decrements in hemodynamic status, renal blood flow, and kidney function incurred following transfusion of banked blood were also prevented by renitrosylation. Collectively, our findings lend support to the idea that transfusions may be causally linked to ischemic events and suggest a simple approach to prevention (i.e., SNO-Hb repletion). If these data are replicated in clinical trials, renitrosylation therapy could have significant therapeutic impact on the care of millions of patients.
Aripiprazole plus Topiramate in Opioid-Dependent Patients with Schizoaffective Disorder: An 8-Week, Open-Label, Uncontrolled, Preliminary Study
Authors: Bruno Antonio , Romeo Vincenzo M. , Pandolfo Gianluca , Scimeca Giuseppe , Zoccali Rocco A. , Muscatello Maria Rosaria A.
Published: June 2013

Background

The aims of this study were to evaluate a combination of aripiprazole and topiramate in the treatment of opioid-dependent patients with schizoaffective disorder undergoing methadone maintenance therapy (MMT) and, further, to taper off patients from methadone treatment.

Methods

Twenty patients who met DSM-IV ( Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition) criteria for opioid dependence and schizoaffective disorder receiving MMT (80 mg/day) were given aripiprazole (10 mg/day) plus topiramate (up to 200 mg/day) for 8 weeks. A methadone dose reduction of 3 mg/day until suspension at week 4 was established.

Results

Aripiprazole plus topiramate was effective in reducing clinical symptoms, and a rapid tapering off of MMT was achieved.

Conclusions

Combining aripiprazole and topiramate may be effective in patients with a dual diagnosis of opioid dependency and schizoaffective disorder.
Daimon and psyche: ethical reflections on a numinous marriage
Authors: Rozuel Cécile
Published: June 2013

The daimon captures the irresistible attraction and danger of the unconscious. When the daimon calls, we are faced with a choice: to work with it or to refuse its call. Either way, the decision is ours, and so is our responsibility for whatever ensues. In this paper, I discuss the moral dimensions of a daimonic encounter and the implications it has for conscious behaviour. In particular, I contend that the paradoxical qualities of the daimon, and its profound effects on our existence, support the moral imperative of honest psychological work.
Diverse novel functions of neutrophils in immunity, inflammation, and beyond
Authors: Mócsai Attila
Published: June 2013

Neutrophils have long been considered simple suicide killers at the bottom of the hierarchy of the immune response. That view began to change 10–20 yr ago, when the sophisticated mechanisms behind how neutrophils locate and eliminate pathogens and regulate immunity and inflammation were discovered. The last few years witnessed a new wave of discoveries about additional novel and unexpected functions of these cells. Neutrophils have been proposed to participate in protection against intracellular pathogens such as viruses and mycobacteria. They have been shown to intimately shape the adaptive immune response at various levels, including marginal zone B cells, plasmacytoid dendritic cells and T cell populations, and even to control NK cell homeostasis. Neutrophils have been shown to mediate an alternative pathway of systemic anaphylaxis and to participate in allergic skin reactions. Finally, neutrophils were found to be involved in physiological and pathological processes beyond the immune system, such as diabetes, atherosclerosis, and thrombus formation. Many of those functions appear to be related to their unique ability to release neutrophil extracellular traps even in the absence of pathogens. This review summarizes those novel findings on versatile functions of neutrophils and how they change our view of neutrophil biology in health and disease.
On the topological full group of a minimal Cantor 𝐙²-system
Authors: Elek Gábor , Monod Nicolas
Published: June 2013

Grigorchuk and Medynets recently conjectured that the topological full group of a minimal Cantor

Z

\mathbf {Z}

-action is amenable. They asked whether the statement holds for all minimal Cantor actions of general amenable groups as well. We answer in the negative by producing a minimal Cantor

Z

2

\mathbf {Z}^2

-action for which the topological full group contains a non-abelian free group.
Finite propagation speed for first order systems and Huygens’ principle for hyperbolic equations
Authors: McIntosh Alan , Morris Andrew
Published: June 2013

We prove that strongly continuous groups generated by first order systems on Riemannian manifolds have finite propagation speed. Our procedure provides a new direct proof for self-adjoint systems and allows an extension to operators on metric measure spaces. As an application, we present a new approach to the weak Huygens’ principle for second order hyperbolic equations.
Diagnosis and Treatment of Perianal Crohn Disease
Authors: de Zoeten Edwin F. , Pasternak Brad A. , Mattei Peter , Kramer Robert E. , Kader Howard A.
Published: June 2013

Inflammatory bowel disease is a chronic inflammatory disorder of the gastrointestinal tract that includes both Crohn disease (CD) and ulcerative colitis. Abdominal pain, rectal bleeding, diarrhea, and weight loss characterize both CD and ulcerative colitis. The incidence of IBD in the United States is 70 to 150 cases per 100,000 individuals and, as with other autoimmune diseases, is on the rise. CD can affect any part of the gastrointestinal tract from the mouth to the anus and frequently will include perianal disease. The first description connecting regional enteritis with perianal disease was by Bissell et al in 1934, and since that time perianal disease has become a recognized entity and an important consideration in the diagnosis and treatment of CD. Perianal Crohn disease (PCD) is defined as inflammation at or near the anus, including tags, fissures, fistulae, abscesses, or stenosis. The symptoms of PCD include pain, itching, bleeding, purulent discharge, and incontinence of stool. In this report, we review and discuss the etiology, diagnosis, evaluation, and treatment of PCD.
Percutaneous Liver Biopsy
Authors: Short Scott S. , Papillon Stephanie , Hunter Catherine J. , Stanley Philip , Kerkar Nanda , Wang Larry , Azen Colleen , Wang Kasper
Published: June 2013

Objective:

The aim of this study was to determine patient factors that predict diagnostic failure or increased risk of bleeding complications following percutaneous liver biopsy in children.

Methods:

A retrospective review of all children undergoing percutaneous liver biopsy at a single institution between July 2008 and July 2011 was performed. Demographics, comorbid conditions, preprocedural diagnoses/indications, procedural details, laboratory data, pathologic diagnosis, and complications were recorded. Continuous data were analyzed by Wilcoxon test and categorical data by Fisher exact test to determine statistical significance.

Results:

Two hundred thirteen children (104 girls) with a median age of 7 years (range 1 week–22 years) underwent 328 percutaneous liver biopsies. Nine (4.2%) experienced a decrease in hemoglobin >2 g/dL, 7 required transfusion (3.3%), and 1 patient died (0.5%). Younger age (1.8 vs 84 months, P = 0.05) and lower preprocedural hematocrit (29.3 vs 34.3, P = 0.05) predicted bleeding complications, whereas the number of biopsies, comorbid conditions, and coagulopathy did not. Sixty‐three (19.2%) biopsies were insufficient for definitive histologic evaluation on initial biopsy in 57 patients. Twenty‐one of 57 patients (37%) underwent repeat percutaneous biopsy and 3 of 57 (8%) underwent surgical biopsy. Biopsy provided definitive diagnosis in 86% of cases when repeat biopsy was performed. Shorter specimen length (1.4 vs 1.7 cm, P < 0.01) and biopsies performed for unexplained elevation of liver function tests (34.9% vs 16.7%, P < 0.01) were predictive of nondiagnosis.

Conclusions:

Percutaneous liver biopsy is safe with a low rate of bleeding‐related complications. Ensuring adequate sample length and careful patient selection may further increase the diagnostic yield.
hARACNe: improving the accuracy of regulatory model reverse engineering via higher-order data processing inequality tests
Authors: Jang In Sock , Margolin Adam , Califano Andrea
Published: June 2013

A key goal of systems biology is to elucidate molecular mechanisms associated with physiologic and pathologic phenotypes based on the systematic and genome-wide understanding of cell context-specific molecular interaction models. To this end, reverse engineering approaches have been used to systematically dissect regulatory interactions in a specific tissue, based on the availability of large molecular profile datasets, thus improving our mechanistic understanding of complex diseases, such as cancer. In this paper, we introduce high-order Algorithm for the Reconstruction of Accurate Cellular Network (hARACNe), an extension of the ARACNe algorithm for the dissection of transcriptional regulatory networks. ARACNe uses the data processing inequality (DPI), from information theory, to detect and prune indirect interactions that are unlikely to be mediated by an actual physical interaction. Whereas ARACNe considers only first-order indirect interactions, i.e. those mediated by only one extra regulator, hARACNe considers a generalized form of indirect interactions via two, three or more other regulators. We show that use of higher-order DPI resulted in significantly improved performance, based on transcription factor (TF)-specific ChIP-chip data, as well as on gene expression profile following RNAi-mediated TF silencing.
Evolution of intratumoral phenotypic heterogeneity: the role of trait inheritance
Authors: Gallaher Jill , Anderson Alexander R. A.
Published: June 2013

A tumour is a heterogeneous population of cells that competes for limited resources. In the clinic, we typically probe the tumour by biopsy, and then characterize it by the dominant genetic clone. But genotypes are only the first link in the chain of hierarchical events that leads to a specific cell phenotype. The relationship between genotype and phenotype is not simple, and the so-called genotype to phenotype map is poorly understood. Many genotypes can produce the same phenotype, so genetic heterogeneity may not translate directly to phenotypic heterogeneity. We therefore choose to focus on the functional endpoint, the phenotype as defined by a collection of cellular traits (e.g. proliferative and migratory ability). Here, we will examine how phenotypic heterogeneity evolves in space and time and how the way in which phenotypes are inherited will drive this evolution. A tumour can be thought of as an ecosystem, which critically means that we cannot just consider it as a collection of mutated cells but more as a complex system of many interacting cellular and microenvironmental elements. At its simplest, a growing tumour with increased proliferation capacity must compete for space as a limited resource. Hypercellularity leads to a contact-inhibited core with a competitive proliferating rim. Evolution and selection occurs, and an individual cell's capacity to survive and propagate is determined by its combination of traits and interaction with the environment. With heterogeneity in phenotypes, the clone that will dominate is not always obvious as there are both local interactions and global pressures. Several combinations of phenotypes can coexist, changing the fitness of the whole. To understand some aspects of heterogeneity in a growing tumour, we build an off-lattice agent-based model consisting of individual cells with assigned trait values for proliferation and migration rates. We represent heterogeneity in these traits with frequency distributions and combinations of traits with density maps. How the distributions change over time is dependent on how traits are passed on to progeny cells, which is our main enquiry. We bypass the translation of genetics to behaviour by focusing on the functional end result of inheritance of the phenotype combined with the environmental influence of limited space.