Time resolved observation of resonant and non-resonant contributions to the nonlinear susceptibility χ(3)

The resonant and nonresonant part of χ(3) are distinguished by their different time behavior. The medium is coherently excited by two picosecond light pulses of defined frequency difference and the state of the system is monitored by a third properly delayed probe pulse. Results are presented on neat liquids of carbontetrachloride and cyclohexane and on the mixture of CCl4: C6H12

High-precision realization of robust quantum anomalous Hall state in a hard ferromagnetic topological insulator

The discovery of the quantum Hall (QH) effect led to the realization of a topological electronic state with dissipationless currents circulating in one direction along the edge of a two dimensional electron layer under a strong magnetic field. The quantum anomalous Hall (QAH) effect shares a similar physical phenomenon as the QH effect, whereas its physical origin relies on the intrinsic spin-orbit coupling and ferromagnetism.Here we report the experimental observation of the QAH state in V-doped (Bi,Sb)2Te3 films with the zero-field longitudinal resistance down to 0.00013+-0.00007h/e2 (~3.35+-1.76 ohm), Hall conductance reaching 0.9998+-0.0006e2/h and the Hall angle becoming as high as 89.993+-0.004degree at T=25mK. Further advantage of this system comes from the fact that it is a hard ferromagnet with a large coercive field (Hc>1.0T) and a relative high Curie temperature. This realization of robust QAH state in hard FMTIs is a major step towards dissipationless electronic applications without external fields.Comment: 16 pages, 4 figures, this is the final version, accepted by Nature Materials, forthcomin

Prediction of Ferromagnetic Ground State of NaCl-type FeN

Ab-initio results for structural and electronic properties of NaCl-type FeN are presented in a framework of plane-wave and ultrasoft pseudopotentials. Competition among different magnetic ordering is examined. We find the ferromagnetic phase stable overall. Stabilization over the unpolarized phase is obtained by splitting one flat t_2g-type band crossing the Fermi energy. A comparison with CrN is considered. We find large differences in the properties of the two systems that can be addressed to the smaller ionicity and magnetization of FeN.Comment: 5 pages, 4 figures, twocolumn latex style Sentence changed in Section III line 1

Annealing of amorphous FexCo100-x nanoparticles synthesized by a modified aqueous reduction using NaBH4

FexCo100−x nanoparticles were synthesized by aqueous reduction in iron (II) sulfate and cobalt (II) sulfate using sodium borohydride and sodium citrate. The initial concentrations of iron and cobalt were varied while maintaining an overall metal concentration of 4.60 mM. Increasing the cobalt content from 0 to 100 at. % decreased the magnetization saturation from 152 to 48 emu/g, as determined by room temperature vibrating sample magnetometry. Annealing the samples at 450 and 600 °C showed an increase in crystallite size. Powder x-ray diffraction and transmission electron microscopy was performed to determine the phases and morphology of the materials

Centre-specific bacterial pathogen typing affects infection-control decision making

Whole-genome sequencing is becoming the de facto standard for bacterial outbreak surveillance and infection prevention. This is accompanied by a variety of bioinformatic tools and needs bioinformatics expertise for implementation. However, little is known about the concordance of reported outbreaks when using different bioinformatic workflows. In this multi-centre proficiency testing among 13 major Dutch healthcare-affiliated centres, bacterial whole-genome outbreak analysis was assessed. Centres who participated obtained two randomized bacterial datasets of Illumina sequences, a Klebsiella pneumoniae and a Vancomycin-resistant Enterococcus faecium, and were asked to apply their bioinformatic workflows. Centres reported back on antimicrobial resistance, multi-locus sequence typing (MLST), and outbreak clusters. The reported clusters were analysed using a method to compare landscapes of phylogenetic trees and calculating Kendall–Colijn distances. Furthermore, fasta files were analysed by state-of-the-art single nucleotide polymorphism (SNP) analysis to mitigate the differences introduced by each centre and determine standardized SNP cut-offs. Thirteen centres participated in this study. The reported outbreak clusters revealed discrepancies between centres, even when almost identical bioinformatic workflows were used. Due to stringent filtering, some centres failed to detect extended-spectrum beta-lactamase genes and MLST loci. Applying a standardized method to determine outbreak clusters on the reported de novo assemblies, did not result in uniformity of outbreak-cluster composition among centres

Interpersonal interactions in instrumental lessons: teacher/students verbal and non-verbal behaviours

This study examined verbal and non-verbal teacher/student interpersonal interactions in higher education instrumental music lessons. Twenty-four lessons were videotaped and teacher/ student behaviours were analysed using a researcher-designed instrument. The findings indicate predominance of student and teacher joke among the verbal behaviours with no substantial gender differences between males and females. Deceit cues were the most frequent among the non-verbal behaviours, with the males displaying more gestures of deceit than the females. Other gender differences include the female students using courting signals towards both teacher groups and the female teachers showing interest towards the male students. The presence of positive verbal and negative non-verbal behaviours highlights the mixed messages present in teaching. Implications for instrumental teaching practice include greater focus on gender differences in interpersonal interactions and visual cues to improve communication and teacher/student relationship in the instrumental studio

Anorgasmia in women

This article reports on the etiology and treatment of anorgasmia. Etiological factors include childhood and adolescent experiences, current individual attitudes, and lifestyle factors, as well as the quality and dynamics of past and present committed relationships. It is important to assess the nature of each of the previously mentioned factors in determining the nature of the orgasmic dysfunction as well as assisting in the development of a treatment plan. Treatment approaches for anorgasmia need to address individual factors (e.g., performance anxiety, poor body image) as well as interpersonal problems. A systemic treatment framework would appear to be the most useful approach to treat this sexual dysfunction, as this type of strategy identifies and treats the difficulties experienced by the anorgasmic woman within the total context of her life. Of course, this approach necessitates the involvement of the partner in therapy, and treatment is unlikely to be effective unless the problems experienced by both the woman and her partner are addressed. Limitations of past research in terms of inadequate evaluation of treatment, low sample sizes, and poorly defined interventions are discussed. Finally, directions for future research to advance our understanding of the most effective treatments for anorgasmia are considered. <br /

Theory of anyon excitons: Relation to excitons of nu=1/3 and nu=2/3 incompressible liquids

Elementary excitations of incompressible quantum liquids (IQL's) are anyons, i.e., quasiparticles carrying fractional charges and obeying fractional statistics. To find out how the properties of these quasiparticles manifest themselves in the optical spectra, we have developed the anyon exciton model (AEM) and compared the results with the finite-size data for excitons of nu=1/3 and nu=2/3 IQL's. The model considers an exciton as a neutral composite consisting of three quasielectrons and a single hole. The AEM works well when the separation between electron and hole confinement planes, h, is larger than the magnetic length l. In the framework of the AEM an exciton possesses momentum k and two internal quantum numbers, one of which can be chosen as the angular momentum, L, of the k=0 state. Existence of the internal degrees of freedom results in the multiple branch energy spectrum, crater-like electron density shape and 120 degrees density correlations for k=0 excitons, and the splitting of the electron shell into bunches for non-zero k excitons. For h larger than 2l the bottom states obey the superselection rule L=3m (m are integers starting from 2), all of them are hard core states. For h nearly 2l there is one-to-one correspondence between the low-energy spectra found for the AEM and the many- electron exciton spectra of the nu=2/3 IQL, whereas some states are absent from the many-electron spectra of the nu=1/3 IQL. We argue that this striking difference in the spectra originates from the different populational statistics of the quasielectrons of charge conjugate IQL's and show that the proper account of the statistical requirements eliminates excessive states from the spectrum. Apparently, this phenomenon is the first manifestation of the exclusion statistics in the anyon bound states.Comment: 26 pages with 9 figures, typos correcte

Female Sexual Function Index Short Version: A MsFLASH Item Response Analysis

The Female Sexual Function Index (FSFI) is a psychometrically sound and popular 19-item self-report measure, but its length may preclude its use in studies with multiple outcome measures, especially when sexual function is not a primary endpoint. Only one attempt has been made to create a shorter scale, resulting in the Italian FSFI-6, later translated into Spanish and Korean without further psychometric analysis. Our study evaluated whether a subset of items on the 19-item English-language FSFI would perform as well as the full-length FSFI in peri- and post-menopausal women. We used baseline data from 898 peri- and post-menopausal women recruited from multiple communities, ages 42–62 years, and enrolled in randomized controlled trials for vasomotor symptom management. Goals were to (1) create a psychometrically sound, shorter version of the FSFI for use in peri- and post-menopausal women as a continuous measure and (2) compare it to the Italian FSFI-6. Results indicated that a 9-item scale provided more information than the FSFI-6 across a spectrum of sexual functioning, was able to capture sample variability, and showed sufficient range without floor or ceiling effects. All but one of the items from the Italian 6-item version were included in the 9-item version. Most omitted FSFI items focused on frequency of events or experiences. When assessment of sexual function is a secondary endpoint and subject burden related to questionnaire length is a priority, the 9-item FSFI may provide important information about sexual function in English-speaking peri- and post-menopausal women