Quantum Oscillations in EuFe2As2 single crystals

Quantum oscillation measurements can provide important information about the Fermi surface (FS) properties of strongly correlated metals. Here, we report a Shubnikov-de Haas (SdH) effect study on the pnictide parent compounds EuFe$_{2}$As$_{2}$ (Eu122) and BaFe$_{2}$As$_{2}$ (Ba122) grown by In-flux. Although both members are isovalent compounds with approximately the same density of states at the Fermi level, our results reveal subtle changes in their fermiology. Eu122 displays a complex pattern in the Fourier spectrum, with band splitting, magnetic breakdown orbits, and effective masses sistematically larger when compared to Ba122, indicating that the former is a more correlated metal. Moreover, the observed pockets in Eu122 are more isotropic and 3D-like, suggesting an equal contribution from the Fe $3d$ orbitals to the FS. We speculate that these FS changes may be responsible for the higher spin-density wave ordering temperature in Eu122.Comment: 5 pages, 4 figure

How to Construct Perfect and Worse-than-Coin-Flip Spoofing Countermeasures: A Word of Warning on Shortcut Learning

Shortcut learning, or `Clever Hans effect` refers to situations where a learning agent (e.g., deep neural networks) learns spurious correlations present in data, resulting in biased models. We focus on finding shortcuts in deep learning based spoofing countermeasures (CMs) that predict whether a given utterance is spoofed or not. While prior work has addressed specific data artifacts, such as silence, no general normative framework has been explored for analyzing shortcut learning in CMs. In this study, we propose a generic approach to identifying shortcuts by introducing systematic interventions on the training and test sides, including the boundary cases of `near-perfect` and `worse than coin flip` (label flip). By using three different models, ranging from classic to state-of-the-art, we demonstrate the presence of shortcut learning in five simulated conditions. We analyze the results using a regression model to understand how biases affect the class-conditional score statistics.Comment: Interspeech 202

Perfil sociodemográfico y psicopatológico de los menores acogidos en Valencia

Removing a child from the biological family is the best option in cases of abuse, neglect or mistreatment, but this resource can be a new stressor, because of its possibility to cause imbalances in different areas. The aim of this study is to value how this situation impacts the children. In order to achieve our aim, we have carefully analyzed children’s sociodemographic and psychopathological characteristics, especially anxiety, depression and social stress. The study involved 116 children from Valencia, aged between two weeks and 18 years old received by foster families. Results, structured into three age levels, show that the foster care, although emerges as a temporary and preventive measure with the aim to return to the biological family, becomes as permanent. In addition, the child does not stabilize in a family and many of them are moved to a care-residency. Tutors consider higher levels of pathology in children under 12 years old than parents. However, between 13 and 18, this trend is reversed and the parents are who report higher levels of pathology, for both depression and anxiety.La separación de un menor de su familia biológica es la mejor opción en casos de abuso, negligencia o maltrato pero este recurso puede suponer en sí mismo un nuevo estresor capaz de provocar desajustes en diferentes áreas. El objetivo de este estudio es ver cómo afecta esta situación a los menores para lo cual hemos analizado detalladamente sus características sociodemográficas y psicopatológicas especialmente la ansiedad, depresión y estrés social. En el estudio han participado 116 menores de Valencia de edades comprendidas entre dos semanas y 18 años acogidos por familias educadoras. Los resultados, estructurados en tres niveles de edad, muestran que el acogimiento, aunque surge como una medida preventiva y temporal cuyo fin es el retorno con la familia biológica, se acaba cronificando. Además, el menor no se estabiliza en una familia, sino que se producen ceses y muchos pasan por residencias. Los tutores consideran niveles más altos de patología en los menores de 12 años que los padres. Sin embargo, entre los de 13 a 18, esta tendencia se invierte y son los padres los que reportan niveles más altos de patología, tanto para la depresión como para la ansiedad

Medical Students Using Cadavers for Procedural Simulation Education

Background: Cadaver dissection remains integrated into the curriculum of numerous medical schools. Aspiring physicians acquire the opportunity to work directly with the human body, which is intricate and tangible, yet have minimal exposure to certain procedural skills applicable­­ to patient care during the first year of their medical training. Our aim was to incorporate the cadaver as part of a process to introduce procedures to a class of first year medical students in order to improve their confidence and skill in performing these procedures in patients. Methods: During medical gross anatomy at Wayne State University School of Medicine, three workshops involving common procedures performed in the emergency department were integrated into the cadaver dissection laboratory. Each educational workshop began with a short demonstration or a short step-by-step informational video on the focused procedure. The educators consisted of emergency medicine residents, third and fourth year medical student mentors, and emergency medicine attendings. Educators directed the hands-on procedure practice on the cadavers and provided real time feedback. Students completed pre and post questionnaires with scales ranging from one to five to assess the impact of the workshop on their abilities and confidence for the specified procedures. The three sessions included intraosseous (IO) line placement, joint aspiration, and chest tube placement. Results: A total of 108 students participated in the IO line training workshop, 143 students in the arthrocentesis simulation and 79 students in the chest tube session. Prior to the hands on sessions, 0 students (0%) had performed an IO line on a simulated patient, 2 students (1.4%) had performed an arthrocentesis on a simulated patient, and 4 students (5.1%) had performed a chest tube on a simulated patient. The Likert scales were viewed as ordinal variables (categorical variables) and thus the data was analyzed by Wilcoxon signed-rank test (non-parametric paired t-test). The student’s confidence in performing the specified procedure improved with a statistically significant difference in the IO, arthrocentesis and chest tube workshops (p = \u3c0.0001). There was a statistically significant increase in the perception of adequate training in all three sessions (p = \u3c 0.0001). The self-perceived skill in performing the described procedures had a statistically significant improvement for post training session in students participating in the IO, arthrocentesis and chest tube workshops (p = \u3c 0.0001). Lastly, after the hands-on educational sessions, a median of 4.5 out of 5 and mode of 5 out of 5 recommended other medical students participate in the IO simulation activity, and a median and mode of 5 out of 5 recommended the arthrocentesis and chest tube workshops. Conclusion: Workshops introducing procedural simulation in the cadaver to first year medical students improved confidence levels, perception of being adequately trained, and self-evaluated skill. Cadavers are effective models for training medical students in common emergency medical procedures. Integrating workshops into existing medical gross anatomy courses may translate into higher procedural success rates in the clinical setting, as well as stimulate interest in understanding normal anatomy and common variants encountered in practice

La hiperresistència del norovirus

Sent una de les malalties més comunes entre la població, la gastroenteritis aguda (GEA) es relaciona habitualment amb els norovirus. Un grup de virus que pot afectar l'estómac i els intestins, i fàcilment transmissibles en espais tancats o per contacte personal, el que explica que habitualment es donin brots epidèmics durant els creuers. Destaquen per la seva capacitat de resistència a pràctiques higièniques o ambients extrems, per la qual cosa es converteixen en una de les primeres causes de malaltia gastrointestinal. Així doncs, el següent article presenta un estudi comparat de les taxes d'afectació per Salmonella i norovirus a Catalunya durant un període de 12 mesos. Els resultats atribueixen a aquest últim una major incidència d'atac i una clara propensió a l'epidèmia, en comparació amb altres agents infecciosos. Per això, proposen unes mesures higienistes més exhaustives.Siendo una de las enfermedades más comunes entre la población, la gastroenteritis aguda (GEA) se relaciona habitualmente con los norovirus. Un grupo de virus que pueden afectar el estómago y los intestinos, y fácilmente transmisibles en espacios cerrados o por contacto personal, lo que explica que habitualmente se den brotes epidémicos durante los cruceros. Destacan por su capacidad de resistencia a prácticas higiénicas o ambientes extremos, por lo que se convierten en una de las primeras causas de enfermedad gastrointestinal. Así pues, el siguiente artículo presenta un estudio comparado de las tasas de afectación por Salmonella y norovirus en Cataluña durante un periodo de 12 meses. Los resultados atribuyen a éste último una mayor incidencia de ataque y una clara propensión a la epidemia, en comparación con otros agentes infecciosos. Por ello, proponen unas medidas higienistas más exhaustivas y dedicar especial atención a los que siempre son los más débiles: ancianos y niños.Acute gastroenteritis (AGE), often related to noroviruses, is one of the most common diseases suffered by the population. Noroviruses affect the stomach and intestines and are easily transmissible through human contact or in enclosed spaces, which would explain why they appear relatively frequently during cruise trips. This group of viruses stands out for its ability to resist good hygiene habits or extreme environments and is one of the main causes of gastrointestinal diseases. The following article presents a comparative study of the index of Salmonella and norovirus cases in Catalonia over a twelve month period. The results show that there is a higher incidence of norovirus attacks and a clear predisposition to cause epidemics when compared to other infectious agencies. Researchers thus propose establishing more exhaustive hygiene measures and that special attention be given to those who always suffer the most: the elderly and children

Impact of pump-signal overlap in S+C+L band discrete Raman amplifiers

We experimentally investigate the impact of pump-signal overlap in ultra-wideband (>13THz) Raman amplifiers and measure the transmission penalty on 30GBaud PM-QPSK signals due to adjacent Raman pumps in a 15dB gain, 150nm (∼18.8THz) S+C+L-band discrete Raman amplifier. We present an efficient numerical model to predict the performance penalty induced by crosstalk from Rayleigh backscattered light from backward-propagating Raman pumps showing good agreement with the experimental results. A 4nm guard-band must be retained around an overlapping Raman pump based on typical, commercial semiconductor laser pump diodes to ensure a negligible transmission penalty in S-ban

Laser cooling of a diatomic molecule

It has been roughly three decades since laser cooling techniques produced ultracold atoms, leading to rapid advances in a vast array of fields. Unfortunately laser cooling has not yet been extended to molecules because of their complex internal structure. However, this complexity makes molecules potentially useful for many applications. For example, heteronuclear molecules possess permanent electric dipole moments which lead to long-range, tunable, anisotropic dipole-dipole interactions. The combination of the dipole-dipole interaction and the precise control over molecular degrees of freedom possible at ultracold temperatures make ultracold molecules attractive candidates for use in quantum simulation of condensed matter systems and quantum computation. Also ultracold molecules may provide unique opportunities for studying chemical dynamics and for tests of fundamental symmetries. Here we experimentally demonstrate laser cooling of the molecule strontium monofluoride (SrF). Using an optical cycling scheme requiring only three lasers, we have observed both Sisyphus and Doppler cooling forces which have substantially reduced the transverse temperature of a SrF molecular beam. Currently the only technique for producing ultracold molecules is by binding together ultracold alkali atoms through Feshbach resonance or photoassociation. By contrast, different proposed applications for ultracold molecules require a variety of molecular energy-level structures. Our method provides a new route to ultracold temperatures for molecules. In particular it bridges the gap between ultracold temperatures and the ~1 K temperatures attainable with directly cooled molecules (e.g. cryogenic buffer gas cooling or decelerated supersonic beams). Ultimately our technique should enable the production of large samples of molecules at ultracold temperatures for species that are chemically distinct from bialkalis.Comment: 10 pages, 7 figure

Robust Voice Liveness Detection and Speaker Verification Using Throat Microphones

While having a wide range of applications, automatic speaker verification (ASV) systems are vulnerable to spoofing attacks, in particular, replay attacks that are effective and easy to implement. Most prior work on detecting replay attacks uses audio from a single acousticmicrophone only, leading to difficulties in detecting high-end replay attacks close to indistinguishable from live human speech. In this paper, we study the use of a special body-conducted sensor, throat microphone (TM), for combined voice liveness detection (VLD) and ASV in order to improve both robustness and security of ASV against replay attacks.We first investigate the possibility and methods of attacking a TM-based ASV system, followed by a pilot data collection. Second, we study the use of spectral features for VLD using both single-channel and dualchannel ASV systems. We carry out speaker verification experiments using Gaussian mixture model with universal background model (GMM-UBM) and i-vector based systems on a dataset of 38 speakers collected by us. We have achieved considerable improvement in recognition accuracy, with the use of dual-microphone setup. In experiments with noisy test speech, the false acceptance rate (FAR) of the dual-microphone GMM-UBM based system for recorded speech reduces from 69.69% to 18.75%. The FAR of replay condition further drops to 0% when this dual-channel ASV system is integrated with the new dual-channel voice liveness detector.</p