Domain configuration and magnetization switching in arrays of permalloy nanostripes

The proximity effect in the collective behavior of arrays of magnetic nanostripes is currently a subject of intensive research. The imperative of reducing the size and distances between elements in order to achieve higher storage capacity, faster access to the information as well as low energy consumption, brings consequences about the isolated behavior of the elements and devices. Parallel to each other permalloy nanostripes with high aspect ratio have been prepared by the nanolithography technique. The evolution of the closure domains and the magnetization direction in individual nanostructures has been imaged under applied magnetic fields using Variable Field Magnetic Force Microscopy. Moreover, the magnetostatic interactions between neighboring elements and the proximity effects in arrays of such nanostructures have been quantitatively analyzed by Magnetic Force Microscopy and micromagnetic simulations. The agreement between simulations and the experimental results allows us to conclude the relevance of those interactions depending on the geometry characteristics. In particular, results suggest that the magnetostatic coupling between adjacent nanostripes vanishes for separation distances higher than 500 nm

Energy Deposition around Swift Carbon-Ion Tracks in Liquid Water

Energetic carbon ions are promising projectiles used for cancer radiotherapy. A thorough knowledge of how the energy of these ions is deposited in biological media (mainly composed of liquid water) is required. This can be attained by means of detailed computer simulations, both macroscopically (relevant for appropriately delivering the dose) and at the nanoscale (important for determining the inflicted radiobiological damage). The energy lost per unit path length (i.e., the so-called stopping power) of carbon ions is here theoretically calculated within the dielectric formalism from the excitation spectrum of liquid water obtained from two complementary approaches (one relying on an optical-data model and the other exclusively on ab initio calculations). In addition, the energy carried at the nanometre scale by the generated secondary electrons around the ion's path is simulated by means of a detailed Monte Carlo code. For this purpose, we use the ion and electron cross sections calculated by means of state-of-the art approaches suited to take into account the condensed-phase nature of the liquid water target. As a result of these simulations, the radial dose around the ion's path is obtained, as well as the distributions of clustered events in nanometric volumes similar to the dimensions of DNA convolutions, contributing to the biological damage for carbon ions in a wide energy range, covering from the plateau to the maximum of the Bragg peak

Electronic excitation spectra of cerium oxides: from ab initio dielectric response functions to Monte Carlo electron transport simulations

Nanomaterials made of the cerium oxides CeO$_2$ and Ce$_2$O$_3$ have a broad range of applications, from catalysts in automotive, industrial or energy operations to promising materials to enhance hadrontherapy effectiveness in oncological treatments. To elucidate the physico-chemical mechanisms involved in these processes, it is of paramount importance to know the electronic excitation spectra of these oxides, which are obtained here through high-accuracy linear-response time-dependent density functional theory calculations. In particular, the macroscopic dielectric response functions $\bar\epsilon$ of both bulk CeO$_2$ and Ce$_2$O$_3$ are derived, which compare remarkably well with the available experimental data. These results stress the importance of appropriately accounting for local field effects to model the dielectric function of metal oxides. Furthermore, we reckon the materials energy loss functions \mbox{Im} (-1/\bar{\epsilon}), including the accurate evaluation of the momentum transfer dispersion from first-principles. In this respect, by using a Mermin-type parametrization we are able to model the contribution of different electronic excitations to the dielectric loss function. Finally, from the knowledge of the electron inelastic mean free path, together with the elastic mean free path provided by the relativistic Mott theory, we carry out statistical Monte Carlo (MC) charge transport simulations to reproduce the major features of the reported experimental reflection electron energy loss (REEL) spectra of cerium oxides. The good agreement with REEL experimental data strongly supports our approach based on MC modelling informed by ab initio calculated electronic excitation spectra in a broad range of momentum and energy transfers.Comment: 21 pages, 19 figure

From floodplain to aquatic sediments: Radiogeochronological fingerprints in a sediment core from the mining impacted Sancho Reservoir (SW Spain)

The Sancho Reservoir (SW Spain) was built in 1962, about the time of maximum 137Cs fallout, and it has been affected by acid mine drainage (AMD) particularly since the mining cease in 2001. This is a unique scenario for studying the radiogeochronological fingerprints in AMD-affected sediments deposited over the former flood plain. A sediment core sampled in 2011 was analysed for bulk density, 137Cs, 239Pu, 240Pu, 210Pb, 226Ra, 228Ra, 234Th (238U) and 40K, and studied with various radiometric dating models. Bulk density revealed unsteady compaction and likely depositional events. The activity concentrations of 226Ra, 228Ra, 234Th (238U) and 40K were uniform down-core, but declining overall in the upper 0–25 cm, revealing changes in provenance except for 238U, which increased in the top 10 cm likely due to its supply by AMD. The AMD fingerprint was also found in the 239+240Pu/137Cs activity ratio, which increased in the top sediment layers. The 137Cs and 239+240Pu profiles show well defined peaks at the same depth, with inventories being about four times higher than the expected integrated atmospheric deposition in the area. The unsupported 210Pb (210Pbexc) showed a complex non-monotonic profile interrupted at several sections, particularly around the 137Cs peak. The whole dataset cannot be interpreted in terms of continuous sedimentation processes. Based upon correlated features in the bulk density and 210Pbexc profiles, a series of depositional events (likely linked to peaks in the rainfall records) have been identified in the core. These events date back to the period comprised since the construction of the dam until its increase in height in 1972, which likely displaced upstream the main depositional area of riverine loads, as inferred from sediment trap data. The CRS (with a reference date) and (a piecewise) CIC models have been used for complementing and discussing the chronology.Ministerio de Economia y Competitividad CTM2015-68628-

Human Papillomavirus (HPV) infection in pregnant women and mother-to-child transmission of genital HPV genotypes: a prospective study in Spain

Background: Studies on HPV infection in pregnant women and HPV transmission to the child have yielded inconsistent results. Methods: To estimate mother-to-child HPV transmission we carried out a prospective cohort study that included 66 HPV-positive and 77 HPV-negative pregnant women and their offspring attending a maternity hospital in Barcelona. To estimate HPV prevalence and genotype distribution in pregnancy we also carried out a related screening survey of cervical HPV-DNA detection among 828 pregnant women. Cervical cells from the mother were collected at pregnancy (mean of 31 weeks) and at the 6-week post-partum visit. Exfoliated cells from the mouth and external genitalia of the infants were collected around birth, at the 6-week post-partum visit, and around 3, 6, 12, and 24 months of age. All samples were tested for HPV using PCR. Associations between potential determinants of HPV infection in pregnant women and of HPV positivity in infants were also explored by logistic regression modelling. Results: Overall cervical HPV-DNA detection in pregnant women recruited in the HPV screening survey was 6.5% (54/828). Sexual behavior-related variables, previous histories of genital warts or sexually transmitted infections, and presence of cytological abnormalities were statistically significantly and positively associated with HPV DNA detection in pregnant women recruited in the cohort. At 418 infant visits and a mean follow-up time of 14 months, 19.7% of infants born to HPV-positive mothers and 16.9% of those born to HPV-negative mothers tested HPV positive at some point during infants' follow-up. The most frequently detected genotype both in infants and mothers was HPV-16, after excluding untyped HPV infections. We found a strong and statistically significant association between mother's and child's HPV status at the 6-week post-partum visit. Thus, children of mothers' who were HPV-positive at the post-partum visit were about 5 times more likely to test HPV-positive than children of corresponding HPV-negative mothers (p = 0.02). Conclusion: This study confirms that the risk of vertical transmission of HPV genotypes is relatively low. HPV persistence in infants is a rare event. These data also indicate that vertical transmission may not be the sole source of HPV infections in infants and provides partial evidence for horizontal mother-to-child HPV transmission

IAA : Información y actualidad astronómica (46)

Sumario: UPWARDS: ciencia nueva para un planeta viejo.-- La teoría del estado estacionario.-- Sorpresas en la nebulosa del Huevo Podrido.-- DECONSTRUCCIÓN Y otros ENSAYOS. Binarias de rayos X.-- Homenaje a Javier Gorosabel.-- EL “MOBY DICK” DE... Christina Thöne (IAA).-- CIENCIA EN HISTORIAS...Maria Mitchell.-- ACTUALIDAD.-- SALA LIMPIA.-- CIENCIA: PILARES E INCERTIDUMBRES. Mercurio.N

The CMS Event Builder

The data acquisition system of the CMS experiment at the Large Hadron Collider will employ an event builder which will combine data from about 500 data sources into full events at an aggregate throughput of 100 GByte/s. Several architectures and switch technologies have been evaluated for the DAQ Technical Design Report by measurements with test benches and by simulation. This paper describes studies of an EVB test-bench based on 64 PCs acting as data sources and data consumers and employing both Gigabit Ethernet and Myrinet technologies as the interconnect. In the case of Ethernet, protocols based on Layer-2 frames and on TCP/IP are evaluated. Results from ongoing studies, including measurements on throughput and scaling are presented. The architecture of the baseline CMS event builder will be outlined. The event builder is organised into two stages with intelligent buffers in between. The first stage contains 64 switches performing a first level of data concentration by building super-fragments from fragments of 8 data sources. The second stage combines the 64 super-fragments into full events. This architecture allows installation of the second stage of the event builder in steps, with the overall throughput scaling linearly with the number of switches in the second stage. Possible implementations of the components of the event builder are discussed and the expected performance of the full event builder is outlined.Comment: Conference CHEP0

Electrodeposited amorphous CoP multilayers with high permeability

Multilayer films composed of Co_(x)P_(1-x) ferromagnetic layers with different composition (0.74 < x < 0.86) have been obtained by varying the electrolytic current during the deposition process. These samples exhibit planar anisotropy, high permeability and a very low coercive force (similar to 5 A/m). The magnetic properties of these samples have been compared with the properties of Co_(x)P_(1-x) multilayers consisting of magnetic and non-magnetic (x < 0.7) layers

Real-life outcomes in biotypes of psychotic disorders based on neurocognitive performance

Producción CientíficaAiming at discerning potential biotypes within the psychotic syndrome, we have recently reported the possible existence of two clusters or biotypes across schizophrenia and bipolar disorder characterized by their cognitive performance using the Brief Assessment of Cognition in Schizophrenia (BACS) instrument and validated with independent biological and clinical indexes (Fernández-Linsenbarth et al. in Schizophr Res 229:102–111, 2021). In this previous work, the group with larger cognitive deficits (N = 93, including 69 chronic schizophrenia, 17 first episodes (FE) of schizophrenia and 7 bipolar disorder patients) showed smaller thalamus and hippocampus volume and hyper-synchronic electroencephalogram than the group with milder deficits (N = 105, including 58 chronic schizophrenia, 25 FE and 22 bipolar disorder patients). We predicted that if these biotypes indeed corresponded to different cognitive and biological substrates, their adaptation to real life would be different. To this end, in the present work we have followed up the patients’ population included in that work at 1st and 3rd years after the date of inclusion in the 2021 study and we report on the statistical comparisons of each clinical and real-life outcomes between them. The first cluster, with larger cognitive deficits and more severe biological alterations, showed during that period a decreased capacity for job tenure (1st and 3rd years), more admissions to a psychiatric ward (1st year) and a higher likelihood for quitting psychiatric follow-up (3rd year). Patients in the second cluster, with moderate cognitive deficits, were less compliant with prescribed treatment at the 3rd year. The differences in real-life outcomes may give additional external validity to that yielded by biological measurements to the described biotypes based on neurocognition.Instituto de Salud Carlos III (grant ID PI18/00178)Dirección Regional de Salud de Castilla y León (grant ID GRS 2121/A/2020)Junta de Castilla y León - predoctoral grants from the Consejería de Educación and the European Social Fund (grant IDs VA-183-18 to IFL and VA- 223-19 to RMBRS)Publicación en abierto financiada por el Consorcio de Bibliotecas Universitarias de Castilla y León (BUCLE), con cargo al Programa Operativo 2014ES16RFOP009 FEDER 2014-2020 DE CASTILLA Y LEÓN, Actuación:20007-CL - Apoyo Consorcio BUCL