Emergency remote teaching and students' academic performance in higher education during the COVID-19 pandemic: A case study.

The COVID-19 pandemic has caused a massive disruption in the way traditional higher education institutions deliver their courses. Unlike transitions from face-to-face teaching to blended, online or flipped classroom in the past, changes in emergency remote teaching -a temporary shift of instructional delivery to an alternate remote delivery mode due to crisis circumstances- happen suddenly and in an unplanned way. This study analyzes the move to emergency remote teaching at the School of Telecommunication Engineering (Universidad Politécnica de Madrid), and the impact of organizational aspects related to unplanned change, instruction-related variables -class size, synchronous/asynchronous delivery- and use of digital supporting technologies, on students' academic performance. Using quantitative data of academic records across all (N = 43) courses of a bachelor's degree programme in Telecommunication Engineering and qualitative data from a questionnaire delivered to all (N = 43) course coordinators, the research also compares the academic results of students during the COVID-19 pandemic with those of previous years. The results of this case study show an increase in students' academic performance in emergency remote teaching, and support the idea that organizational factors may contribute to successful implementation of emergency remote teaching; the analysis does not find differences across courses with different class sizes or delivery modes. The study further explores possible explanations for the results of the analysis, considering organizational, individual and instruction-related aspects.

The search process: Integrating the investigation and identification of missing and unidentified persons.

The effective search for the missing and identification of persons, alive or dead, are core components in the prevention and in resolving the issue of Missing Persons. Despite the growing literature on this topic, there is still a lack of publications describing the Search as a process that includes different phases inherently composed of forensic investigative and identification principles for both living and deceased missing persons. This paper is the result of discussions between the Forensic Unit of the International Committee of the Red Cross (ICRC) and members of its external Forensic Advisory Board. It aims to present the Search process as an overarching concept that includes the investigation and identification phases of the missing in any state (dead or alive), in any scenario (with or without bodies), with an integrated, multidisciplinary, and multiagency approach for implementation by all actors involved in the investigation and identification phases of missing persons.

Recomendaciones de expertos en la mejora de la prevención efectiva del ictus isquémico en la fibrilación auricular no valvular: papel del rivaroxabán / Expert recommendations on improving effective ischemic stroke prevention in nonvalvular atrial fibrillation: the role of rivaroxaban

La fibrilación auricular aumenta de manera marcada el riesgo de ictus isquémico. A pesar de que los antagonistas de la vitamina K (AVK) reducen ese riesgo, tienen una eficacia limitada y numerosos inconvenientes que han hecho que durante años hubiese una proporción importante de pacientes con fibrilación auricular no anticoagulados. En cambio, no solo los ensayos clínicos, sino también los estudios en práctica clínica real y últimamente los estudios poblacionales, han demostrado que los anticoagulantes orales de acción directa (ACOD) tienen más eficacia y seguridad y un mejor beneficio clínico neto que los AVK. De hecho, en las regiones donde la prescripción de ACOD es mayor, está disminuyendo la incidencia de ictus isquémico, además de los costes generales asociados con la fibrilación auricular. A pesar de que en los últimos años ha aumentado la prescripción de ACOD, España es de los países con menores tasas de prescripción de toda Europa, lo que podría asociarse con mayores tasas de ictus isquémico. A pesar de que todas las guías posicionan los ACOD como de primera elección frente a los AVK para los pacientes con fibrilación auricular no valvular, en España, debido a las restricciones impuestas por el informe de posicionamiento terapéutico, con necesidad de visado, y también por la inercia terapéutica, es mayor la prescripción de AVK. Son necesarias medidas inmediatas para corregir esta situación, y así mejorar el pronóstico de nuestros pacientes

Atrial fibrillation markedly increases the risk of ischemic stroke. Although vitamin K antagonists (VKAs) reduce this risk, they have limited efficacy and several disadvantages, which has meant that over the years a substantial proportion of patients with atrial fibrillation have remained without anticoagulation. In contrast, clinical trials, studies in routine clinical practice and, more recently, population-based studies have all demonstrated that direct oral anticoagulants (DOACs) are more effective and safer than VKAs and also have a greater net clinical benefit. In fact, in regions where the DOAC prescription rate is high, the incidence of ischemic stroke has decreased, as have the overall costs associated with atrial fibrillation. Although the prescription of DOACs in Spain has increased in recent years, the country has one of the lowest prescription rates in Europe, which may be associated with a higher incidence of ischemic stroke. Despite clinical guidelines all recommending that DOACs should be used in preference to VKAs in patients with nonvalvular atrial fibrillation, more prescriptions are issued for VKAs in Spain, largely due to restrictions imposed by national statements on appropriate medicine use (including the need for approval), but also because of therapeutic inertia. Immediate action should be taken to correct this situation and to improve patients' prognoses

Observation of a topologically protected state in a magnetic domain wall stabilized by a ferromagnetic chemical barrier.

The precise control and stabilization of magnetic domain walls is key for the development of the next generation magnetic nano-devices. Among the multitude of magnetic configurations of a magnetic domain wall, topologically protected states are of particular interest due to their intrinsic stability. In this work, using XMCD-PEEM, we have observed a topologically protected magnetic domain wall in a ferromagnetic cylindrical nanowire. Its structure is stabilized by periodic sharp alterations of the chemical composition in the nanowire. The large stability of this topologically protected domain wall contrasts with the mobility of other non-protected and non-chiral states also present in the same nanowire. The micromagnetic simulations show the structure and the conditions required to find the topologically protected state. These results are relevant for the design of future spintronic devices such as domain wall based RF oscillators or magnetic memories.

¿Es suficiente el cribado actual para el virus de la inmunodeficiencia humana? A propósito de un caso de un control de calidad / Current human immunodeficiency virus screening: Is it enough? A quality control report case

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Dental age estimation in Spanish children.

The objective of this study was to apply the method for calculating dental age proposed by Demirjian et al. to a sample of Spanish children, followed by a comparison between their dental and chronological ages. This study also set out to create tables to convert specific dental age using the maturity data from our sample. This study was performed on a sample of 1010 orthopantograms taken of Spanish children (485 boys and 525 girls) aged 2-16. We found that the mean estimated dental age exceeded the mean chronological age in both boys and girls, with the mean difference being 0.87 and 0.55 years respectively. We adapted Demirjian's method to our study sample to obtain specific conversion tables and curves.

NOL11, implicated in the pathogenesis of North American Indian childhood cirrhosis, is required for pre-rRNA transcription and processing.

The fundamental process of ribosome biogenesis requires hundreds of factors and takes place in the nucleolus. This process has been most thoroughly characterized in baker's yeast and is generally well conserved from yeast to humans. However, some of the required proteins in yeast are not found in humans, raising the possibility that they have been replaced by functional analogs. Our objective was to identify non-conserved interaction partners for the human ribosome biogenesis factor, hUTP4/Cirhin, since the R565W mutation in the C-terminus of hUTP4/Cirhin was reported to cause North American Indian childhood cirrhosis (NAIC). By screening a yeast two-hybrid cDNA library derived from human liver, and through affinity purification followed by mass spectrometry, we identified an uncharacterized nucleolar protein, NOL11, as an interaction partner for hUTP4/Cirhin. Bioinformatic analysis revealed that NOL11 is conserved throughout metazoans and their immediate ancestors but is not found in any other phylogenetic groups. Co-immunoprecipitation experiments show that NOL11 is a component of the human ribosomal small subunit (SSU) processome. siRNA knockdown of NOL11 revealed that it is involved in the cleavage steps required to generate the mature 18S rRNA and is required for optimal rDNA transcription. Furthermore, abnormal nucleolar morphology results from the absence of NOL11. Finally, yeast two-hybrid analysis shows that NOL11 interacts with the C-terminus of hUTP4/Cirhin and that the R565W mutation partially disrupts this interaction. We have therefore identified NOL11 as a novel protein required for the early stages of ribosome biogenesis in humans. Our results further implicate a role for NOL11 in the pathogenesis of NAIC.

Permanent teeth development in a Spanish sample. Application to dental age estimation.

The purpose of this study is to clarify the chronology of different stages of dental development, according to Demirjian, in a sample of Spanish children, which will enable us to build a database that will be used as a reference in regard to the dental development of individuals of our socio-geographic environment. In the same studied sample, a calculation of the dental age according to Demirjian was carried out. This study was conducted in a final sample consisting of 1010 orthopantograms, corresponding to Spanish children (485 boys and 525 girls) ages 2-16. Comparing the age of onset of the different stages among the children, evidence was found that girls had an earlier general development than boys. These differences were only statistically significant in teeth and concrete stages. The canine teeth revealed greater gender dimorphism, with significant differences in all stages compared with the upper canines. The method proposed by Demirjian for dental age calculation resulted in a significant overestimation of dental age in relation to the chronological age in boys (average of 0.87 years) and girls (average of 0.55 years). Data from this study may be used as reference for dental maturity, as well as a standard for estimating age in Spanish children.

Replication timing of pseudo-NORs.

In mammalian cells, transcriptionally active ribosomal genes are replicated in the early S phase, and the silent ribosomal genes in the late S phase, though mechanisms of this timing remain unknown. UBF (Upstream Binding Factor), a DNA binding protein and component of the pol I transcription machinery, is considered to be responsible for the loose chromatin structure of the active rDNA. Here we question whether such structure alone can ensure early replication of DNA. We investigate this problem on the model of pseudo-NORs, the tandem arrays of heterologous DNA sequence with high affinity for UBF, introduced into human chromosomes. Such arrays are not transcribed, yet efficiently bind UBF and mimic the chromatin structure of active rDNA. In our study, a human derived stable cell line containing one pseudo-NOR on the chromosome 10 was transiently transfected with UBF-GFP and PCNA-RFP, which allowed us to observe in vivo the growth of pseudo-NORs resulted from their replication. We found that replication of pseudo-NORs is not restricted to the early S phase, but continues in the late S phase at a significant level. These results were confirmed in the experiments with incorporation of thymidin analog EdU and BrdU ChIP assay. Similar results were obtained with another cell line containing pseudo-NOR on the chromosome 7. Our data indicate that the specific loose structure of chromatin, produced by the architect protein UBF, is not sufficient for the early replication.

A novel small-subunit processome assembly intermediate that contains the U3 snoRNP, nucleolin, RRP5, and DBP4.

Eukaryotic 18S rRNA processing is mediated by the small subunit (SSU) processome, a machine comprised of the U3 small nucleolar RNP (U3 snoRNP), tUTP, bUTP, MPP10, and BMS1/RCL1 subcomplexes. We report that the human SSU processome is a dynamic structure with the recruitment and release of subcomplexes occurring during the early stages of ribosome biogenesis. A novel 50S U3 snoRNP accumulated when either pre-rRNA transcription was blocked or the tUTP proteins were depleted. This complex did not contain the tUTP, bUTP, MPP10, and BMS1/RCL1 subcomplexes but was associated with the RNA-binding proteins nucleolin and RRP5 and the RNA helicase DBP4. Our data suggest that the 50S U3 snoRNP is an SSU assembly intermediate that is likely recruited to the pre-rRNA through the RNA-binding proteins nucleolin and RRP5. We predict that nucleolin is only transiently associated with the SSU processome and likely leaves the complex not long after 50S U3 snoRNP recruitment. The nucleolin-binding site potentially overlaps that of several other key factors, and we propose that this protein must leave the SSU processome for pre-rRNA processing to occur.

La Antropología Forense en España desde la perspectiva de la medicina forense / Forensic anthropology in Spain from the forensic medicine perspective

mundo de forma diferente en respuesta a criterios específicosde cada país, especialmente en función de consideracioneshistóricas relativas al enfoque de las investigacionesforenses, su organización profesional, el papel queel antropólogo forense juega en ellas y los sistemas deformación existentes.En España, los problemas asociados a la identificaciónen el ámbito legal han estado invariablemente asociadosa la Medicina legal y Forense cuyo origen, en suetapa moderna, coincide con el de la propia Antropología,en la que médicos y naturalistas han tenido un impactosignificativo.A pesar del camino recorrido, la Antropología forensees una disciplina en desarrollo en España, como se evidenciapor el incremento de la demanda formativa y delos textos y artículos publicados, cada vez con mayor frecuenciaen los últimos años(AU)

Forensic anthropology has developed in differentways across the world in response to specific countrycriteria in approaches to forensic investigations, the rolethat the forensic anthropologist plays in these investigationsand their background and/or the type of training systemimplemented.In Spain, identification when dealing with livingsubjects and that of the deceased in the legal sphere, is anactivity clearly linked to legal and forensic medicine, usuallypractised inside the organisational system of forensicmedicine. Otherwise, the origin of modern forensicmedicine and anthropology, on which doctors andnaturalists had a significant impact, is coincident in time.In spite of the way covered, forensic anthropology isa growing scientific discipline in Spain, as evidenced by theincrease in specific courses, texts and articles published innational and international journals, becoming more andmore frequently in recent years(AU)

Pseudo-NORs: a novel model for studying nucleoli.

Nucleolar organiser regions (NORs) are comprised of tandem arrays of ribosomal gene (rDNA) repeats that are transcribed by RNA polymerase I (Pol I), ultimately resulting in formation of a nucleolus. Upstream binding factor (UBF), a DNA binding protein and component of the Pol I transcription machinery, binds extensively across the rDNA repeat in vivo. Pseudo-NORs are tandem arrays of a heterologous DNA sequence with high affinity for UBF introduced into human chromosomes. In this review we describe how analysis of pseudo-NORs has provided important insights into nucleolar formation. Pseudo-NORs mimic endogenous NORs in a number of important respects. On metaphase chromosomes both appear as secondary constrictions comprised of undercondensed chromatin. The transcriptional silence of pseudo-NORs provides a platform for studying the transcription independent recruitment of factors required for nucleolar formation by this specialised chromatin structure. During interphase, pseudo-NORs appear as distinct and novel sub-nuclear bodies. Analysis of these bodies and comparison to their endogenous counterpart has provided insights into nucleolar formation and structure.

Linfedema post-quirúrgico en paciente con insuficiencia renal crónica: presentación de un caso / Post-surgical lymphedema in a patient with chronic renal failure: a case presentation

Se presenta el caso de un paciente masculino con antecedentes de una piodermitis y síndrome nefrótico, que posteriormente realiza un síndrome rápidamente progresivo por lo que fue hospitalizado y tratado con anterioridad y que ingresó en esta ocasión con cuadro clínico de inflamación generalizada, decaimiento, palidez cutáneo-mucosa, lesiones residuales en piel. Se constata disfunción renal, se inicia tratamiento hemodialítico por lo que se hace necesario realizar acceso vascular permanente (Fístula Arteriovenosa) para continuar con tratamiento sustitutivo de la función renal (Hemodiálisis) y posteriormente a la realización del acceso vascular se produce un gran aumento de volumen a nivel del miembro superior derecho, compatible con gran Linfedema post-quirúrgico. Teniendo en cuenta lo interesante del caso decidimos realizar este trabajo (AU)

It is presented a masculine patient with antecendents of pyoderma and nephrotic syndrome,that later on presents a rapidly progressive syndrome by which he was hospitalized and treated before and who enter the hospital this time with a clinical picture of generalized inflammation, lassitude, cutaneo-mucous paleness, skin residual injuries. It is noticed renal malfunction, it is iniciated the hemodialytic treatment and that´s the reason why it is necessary to do permanent vascular access (arteriovenous fistula) to carry on with the substitute treatment of renal function (hemodialysis) and after the vascular access it is produced a great increase of volume in right superior member, compatible with post-surgical lymphedema. Taking into account how interesting is this topic, we decide to work on it (AU)

Recruitment of factors linking transcription and processing of pre-rRNA to NOR chromatin is UBF-dependent and occurs independent of transcription in human cells.

Efficient ribosome biogenesis requires coordination of a highly complex series of events. Early events include pre-RNA transcription, processing, and modification. Analysis in yeast has demonstrated that t-UTPs, components of the U3 snoRNA-containing pre-rRNA processing complex, are required for efficient transcription of ribosomal genes (rDNA) by RNA polymerase I (pol I). Here, we characterize human t-UTPs and establish that their ability to link transcription and pre-rRNA processing is evolutionarily conserved. The pol I transcription factor UBF binds extensively across rDNA throughout the cell cycle, resulting in a specialized form of chromatin that is the hallmark of active nucleolar organizer regions (NORs). Transcriptionally silent pseudo-NORs are ectopic, chromosomally integrated, artificial arrays that mimic this specialized chromatin structure. Pseudo-NORs sequester t-UTPs and factors linking transcription with pre-rRNA modification (Nopp140 and Treacle). Recruitment is independent of transcription, the underlying DNA sequence, and location within the nucleolus. Previously, we have demonstrated that pseudo-NORs sequester every component of the pol I transcription machinery. Taken together, these results highlight the importance of the specialized chromatin structure at active NORs in coordinating early events in ribosome biogenesis and nucleolar formation.

A role for upstream binding factor in organizing ribosomal gene chromatin.

Human ribosomal genes are located in NORs (nucleolar organizer regions) on the short arms of acrocentric chromosomes. During metaphase, previously active NORs appear as prominent chromosomal features termed secondary constrictions, which are achromatic in chromosome banding and positive in silver staining. The architectural RNA polymerase I transcription factor UBF (upstream binding factor) binds extensively across the ribosomal gene repeat throughout the cell cycle. Evidence that UBF underpins NOR structure is provided by an examination of cell lines in which large arrays of a heterologous UBF binding sequences are integrated at ectopic sites on human chromosomes. These arrays efficiently recruit UBF even to sites outside the nucleolus, and during metaphase form novel silver-stainable secondary constrictions, termed pseudo-NORs, that are morphologically similar to NORs.

Light echoes from ancient supernovae in the Large Magellanic Cloud.

The light from historical supernovae could in principle still be visible as scattered-light echoes centuries after the explosion. The detection of light echoes could allow us to pinpoint the supernova event both in position and age and, most importantly, permit the acquisition of spectra to determine the 'type' of the supernova centuries after the direct light from the explosion first reached Earth. Although echoes have been discovered around some nearby extragalactic supernovae, targeted searches have not found any echoes in the regions of historical Galactic supernovae. Here we report three faint variable-surface-brightness complexes with high apparent proper motions pointing back to three of the six smallest (and probably youngest) previously catalogued supernova remnants in the Large Magellanic Cloud, which are believed to have been thermonuclear (type Ia) supernovae. Using the distance and apparent proper motions of these echo arcs, we estimate ages of 610 and 410 years for two of them.

UBF-binding site arrays form pseudo-NORs and sequester the RNA polymerase I transcription machinery.

Human ribosomal genes (rDNA) are located in nucleolar organizer regions (NORs) on the short arms of acrocentric chromosomes. Metaphase NORs that were transcriptionally active in the previous cell cycle appear as prominent chromosomal features termed secondary constrictions that are achromatic in chromosome banding and positive in silver staining. The architectural RNA polymerase I (pol I) transcription factor UBF binds extensively across rDNA throughout the cell cycle. To determine if UBF binding underpins NOR structure, we integrated large arrays of heterologous UBF-binding sequences at ectopic sites on human chromosomes. These arrays efficiently recruit UBF even to sites outside the nucleolus and, during metaphase, form novel silver stainable secondary constrictions, termed pseudo-NORs, morphologically similar to NORs. We demonstrate for the first time that in addition to UBF the other components of the pol I machinery are found associated with sequences across the entire human rDNA repeat. Remarkably, a significant fraction of these same pol I factors are sequestered by pseudo-NORs independent of both transcription and nucleoli. Because of the heterologous nature of the sequence employed, we infer that sequestration is mediated primarily by protein-protein interactions with UBF. These results suggest that extensive binding of UBF is responsible for formation and maintenance of the secondary constriction at active NORs. Furthermore, we propose that UBF mediates recruitment of the pol I machinery to nucleoli independently of promoter elements.