3,180 research outputs found

    Broadband transverse susceptibility in multiferroic Y-type hexaferrite Ba0.5Sr1.5Zn2Fe12O22

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    Producción CientíficaNoncollinear spin systems with magnetically induced ferroelectricity from changes in spiral magnetic ordering have attracted significant interest in recent research due to their remarkable magnetoelectric effects with promising applications. Single phase multiferroics are of great interest for these new multifunctional devices, being Y-type hexaferrites good candidates, and among them the ZnY compounds due to their ordered magnetic behaviour over room temperature. Polycrystalline Y type hexaferrites with composition Ba0.5Sr1.5Zn2Fe2O22 (BSZFO) were sintered in 1050 °C–1250 °C temperature range. Transverse susceptibility measurements carried out on these BSZFO samples in the temperature range 80–350 K with DC fields up to ± 5000 Oe reveal different behaviour depending on the sintering temperature. Sample sintered at 1250 °C is qualitatively different, suggesting a mixed Y and Z phase like CoY hexaferrites. Sintering at lower temperatures produce single phase Y-type, but the transverse susceptibility behaviour of the sample sintered at 1150 °C is shifted at temperatures 15 K higher. Regarding the DC field sweeps the observed behaviour is a peak that shifts to lower values with increasing temperature, and the samples corresponding to single Y phase exhibit several maxima and minima in the 250 K–330 K range at low DC applied field as a result of the magnetic field induced spin transitions in this compound.Ministerio de Ciencia, Innovación y Universidades; Agencia Estatal de Investigación with FEDER (MAT2016-80784-P

    The central parsecs of M87: jet emission and an elusive accretion disc

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    We present the first simultaneous spectral energy distribution (SED) of M87 core at a scale of 0.4 arcsec (32pc\sim 32\, \rm{pc}) across the electromagnetic spectrum. Two separate, quiescent, and active states are sampled that are characterized by a similar featureless SED of power-law form, and that are thus remarkably different from that of a canonical active galactic nuclei (AGN) or a radiatively inefficient accretion source. We show that the emission from a jet gives an excellent representation of the core of M87 core covering ten orders of magnitude in frequency for both the active and the quiescent phases. The inferred total jet power is, however, one to two orders of magnitude lower than the jet mechanical power reported in the literature. The maximum luminosity of a thin accretion disc allowed by the data yields an accretion rate of <6×105Myr1< 6 \times 10^{-5}\, \rm{M_\odot \, yr^{-1}}, assuming 10% efficiency. This power suffices to explain M87 radiative luminosity at the jet-frame, it is however two to three order of magnitude below that required to account for the jet's kinetic power. The simplest explanation is variability, which requires the core power of M87 to have been two to three orders of magnitude higher in the last 200 yr. Alternatively, an extra source of power may derive from black hole spin. Based on the strict upper limit on the accretion rate, such spin power extraction requires an efficiency an order of magnitude higher than predicted from magnetohydrodynamic simulations, currently in the few hundred per cent range.Comment: 18 pages, 6 figures. Accepted for publication in MNRA

    Features of non-kinship foster care children with birth family contact in Andalusia

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    The aim of the presentation is to describe the personal features of non-kinship foster care children who have visits with their birth family in Málaga, Granada and Jaén (provinces of Andalusia, Spain). This study was funded by the research project Application of a psychoeducational intervention program to improve visits between foster children and their biological families (Reference EDU2016 77094-P). SPSS v.21.0 was used to carry out the descriptive and frequency analysis of socio-demographic information collected by the Child File Summary Form designed for this study. There are 212 non-kinship foster care children who have visits with their birth family. Their mean age is 8.09 years old (SD= 4.73). The more frequent types of foster care are both long-term and short-term placement (30.7%, respectively), followed by specialized long-term foster care (20.3%), urgency placement (10.8%) and specialized short-term foster care (7.5%). The period of time they have been into the Child Protection System is on average 4.08 years (SD= 3.88) and into the current placement is on average 2.53 (SD= 2.95). Thus, 44.8% of foster children were in residential care and 30.2% were in previous foster care. The latter could have been with the current foster care family. Also, 41.0% of foster children were placed at least with one sibling. It is important to know the features of foster children in order to apply the main principle of “the best interests of the child” to the whole decision-making process about the child’s protection and welfare. In our project, these decisions concern foster care placement and birth family contact to maintain and strengthen family affective bonds and child’s identity formation. Our findings contribute to develop: (a) initiatives to improve children’s well-being; (b) support and social resources required by families; and (c) socio-educative tools for the social workers.Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tech

    Chemotherapy-free treatments: are we ready for prime time?

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    Epithelial ovarian cancer (EOC) is most frequently diagnosed at an advanced stage and, despite high response rates to initial taxane-platinum-based chemotherapy, more than 70% of patients will develop recurrent disease and will receive several chemotherapy treatments. At present, the 5-year overall survival (OS) for women diagnosed with stage III–IV disease is 46% and patients with genetic impairments of DNA repair pathways [BRCA mutations and in general homologous recombination deficiency (HRD)] live longer and possibly will receive even more lines of chemotherapy

    Integrin Signaling Regulates Spindle Orientation in Drosophila to Preserve the Follicular-Epithelium Monolayer

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    SummaryEpithelia act as important physiological barriers and as structural components of tissues and organs. In the Drosophila ovary, follicle cells envelop the germline cysts to form a monolayer epithelium. During division, the orientation of the mitotic spindle in follicle cells is such that both daughter cells remain within the same plane, and the simple structure of the follicular epithelium is thus preserved. Here we show that integrins, heterodimeric transmembrane receptors that connect the extracellular matrix to the cell's cytoskeleton [1, 2], are required for maintaining the ovarian monolayer epithelium in Drosophila. Mosaic egg chambers containing integrin mutant follicle cells develop stratified epithelia at both poles. This stratification is due neither to abnormal cell proliferation nor to defects in the apical-basal polarity of the mutant cells. Instead, integrin function is required for the correct orientation of the mitotic apparatus both in mutant cells and in their immediately adjacent wild-type neighbors. We further demonstrate that integrin-mediated signaling, rather than adhesion, is sufficient for maintaining the integrity of the follicular epithelium. The above data show that integrins are necessary for preserving the simple organization of a specialized epithelium and link integrin-mediated signaling to the correct orientation of the mitotic spindle in this epithelial cell type

    A dark energy multiverse

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    We present cosmic solutions corresponding to universes filled with dark and phantom energy, all having a negative cosmological constant. All such solutions contain infinite singularities, successively and equally distributed along time, which can be either big bang/crunchs or big rips singularities. Classicaly these solutions can be regarded as associated with multiverse scenarios, being those corresponding to phantom energy that may describe the current accelerating universe

    When A Nonnative Accent Lets You Spot All the Errors: Examining the Syntactic Interlanguage Benefit

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    Published August 01 2022In our continuously globalizing world, cross-cultural and cross-linguistic communications are far from exceptional. A wealth of research has indicated that the processing of nonnative-accented speech can be challenging for native listeners, both at the level of phonology. However, few online studies have examined the underpinnings of accented speech recognition from the perspective of the nonnative listener, even though behavioral studies indicate that accented input may be easier to process for such individuals (i.e., the interlanguage speech intelligibility benefit. The current EEG study first examined the phonological and syntactic analysis of nonnative-accented speech among nonnative listeners. As such, 30 English learners of Spanish listened to syntactically correct and incorrect Spanish sentences produced in native and nonnative-accented Spanish. The violation in the incorrect sentences was caused by errors that are typical (i.e., gender errors; *la color) or atypical (i.e., number errors; *los color) for English learners of Spanish. Results indicated that nonnative listeners elicit a phonological mismatch negativity (PMN) when attending to speech produced by a native Spanish speaker. Furthermore, the nonnative listeners showed a P600 for all grammatical violations, indicating that they repair all errors regardless of their typicality or the accent in which they are produced. Follow-up analyses compared our novel data to the data of native listeners from the methodologically identical precursor study. These analyses showed that native and nonnative listeners exhibit directionally opposite PMN effects; whereas natives exhibited a larger PMN for English-accented Spanish, nonnatives displayed a larger PMN in response to native Spanish utterances (a classic interlanguage speech intelligibility benefit). An additional difference was observed at the syntactic level: Whereas natives repaired only atypical number errors when they were English-accented, nonnative participants exhibited a P600 in response to all English-accented syntactic errors, regardless of their typicality (a syntactic interlanguage speech intelligibility benefit). Altogether, these results suggest that accented speech is not inherently difficult to process; in fact, nonnatives may benefit from the presence of a nonnative accent. Thus, our data provide some of the first electrophysiological evidence supporting the existence of the classic interlanguage speech intelligibility benefit and its novel syntactic counterpartThis international collaboration was made possible by a Globalink Research Abroad Award (https://dx.doi.org/10 .13039/501100004489) conferred to the first author. The research was supported by the Spanish Ministry of Economy and Competitiveness (CEX2020-001010-S to the BCBL; PID2020-113926GB-I00 to C. D. M.), the Basque government (PIBA18_29 to C. D. M.). This project has received funding from the European Research Council (ERC) under the European Union’s Horizon 2020 research and innovation program (https://dx.doi.org/10.13039 /100010663), grant number: 819093 to C. D. M., the European Union’s Horizon 2020 research and innovation programme under Marie Sklodowska-Curie (https://dx.doi .org/10.13039/100010663), grant number: 837228 (H2020- MSCA-IF-2018-837228) and the Rita Levi Montalcini fellowship to S. C

    Detección específica de Arcobacter Butzleri en carne de pollo mediante una técnica de PCR

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    En este trabajo se describe el desarrollo de una técnica de PCR para la detección específica de Arcobacter butzleri en carne fresca de pollo empleando cebadores específicos de especie diseñados en gen 16S ARN ribosómico. Los cebadores seleccionados amplifican un fragmento de 195 pb en A. butzleri, sin producir señal de amplificación en otras especies de Arcobacter, Campylobacter, Helicobacter, ni en otros microorganismos presentes en los alimentos. La técnica de PCR se ha aplicado al análisis de 42 muestras comerciales de carne fresca de pollo adquiridas en diversos comercios minoristas. Tras un pre enriquecimiento selectivo durante 18 h a 30ºC, A. butzleri se detectó en un 85,7% de las muestras analizadas. Se observó una total concordancia entre los resultados obtenidos por PCR y el método convencional de recuento en placas de agar selectivo.A PCR technique was developed for the specific detection of Arcobacter butzleri in fresh chicken meat using species-specific primers designed on the 16S ribosomal ARN gene. The selected primers amplify a 195 bp fragment from A. butzleri whereas no PCR product is generated for other Arcobacter, Campylobacter, Helicobacter species, and other food bacteria. The PCR technique was used to screen 42 retail-purchased chicken samples for the presence of A. butzleri. Following a selective enrichment for 18 h at 30ºC, A butzleri was detected in 85.7% of the analyzed samples, showing a total concordance between the PCR results and the conventional selective plating method
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