On the role of soft gluons in collinear parton densities

The role of soft (non-perturbative) gluons in collinear parton densities is investigated with the Parton Branching method as a solution of the DGLAP evolution equations. It is found that soft gluons contribute significantly to collinear parton densities. Within the Parton Branching frame, the Sudakov form factor can be split into a perturbative and non-perturbative part. The non-perturbative part can be calculated analytically under certain conditions. It is shown that the inclusion of soft (non-perturbative) gluons to the parton density evolution is essential for the proper cancellation of divergent terms. It is argued that the non-perturbative part of the Sudakov form factor has its correspondence in Transverse Momentum Dependent parton distributions. Within the Parton Branching approach, this non-perturbative Sudakov form factor is constrained by fits of inclusive, collinear parton densities. We show that the non-perturbative Sudakov form factor and soft gluon emissions are essential for inclusive distributions (collinear parton densities and Drell-Yan transverse momentum spectra), while those soft gluons play essentially no role in final state hadron spectra.Comment: Significantly updated including studies on parton shower and hadronizatio

Global emergency remote education in secondary schools during the COVID-19 pandemic: A systematic review

The worldwide shift to emergency remote education in 2020 as a result of the COVID-19 pandemic impacted billions of students and teachers. A range of teaching and learning strategies were employed by schools as a result, despite confusing and sometimes contradictory government guidance, with systemic issues such as equity and access impacting heavily on disadvantaged students. In light of the findings of a recent IPPO evidence snapshot and roundtable event, and in order to gain further insight into how emergency remote education was experienced by secondary school students, parents and educators, a systematic review was conducted that collates and synthesises primary empirical studies across five key research questions focusing on student engagement, online assessment, peer collaboration, parent engagement, and future directions for online learning. Studies were searched for in May 2021 using Web of Science, Scopus, ERIC, Microsoft Academic Graph, ResearchGate and the COVID-19 living map, and were included if they focused on teaching and learning using blended or online approaches in secondary schools during the pandemic, that were published in English. Following quality assessment on scope and methodological rigour, 81 studies were included for narrative synthesis. The research studies were conducted in 38 countries, with 37% of studies from low or lower-middle income countries, and 63% from upper-middle income or high-income countries. Most of the evidence came from students (64%), followed by teachers (53%), with very few studies exploring the perceptions and experiences of parents (6%) or school leaders (5%). Findings reveal that self-regulation and understanding were the most frequently reported indicators of student engagement, with online assessment tools, learning management systems with collaborative tools, live synchronous lessons with peer and teacher interaction, and teacher-made videos considered particularly engaging. Social isolation was the most frequently reported indicator of disengagement, characterised by poor attendance in live lessons, a lack of opportunities to seek help with challenges and difficulties facilitating peer collaboration. Although many articles reported that assessment online was particularly challenging, 21 different types of online assessments strategies were identified, with online quizzes and formative online feedback the most frequently used. Live marking or recorded feedback and assessment were found to be particularly beneficial, as providing feedback during live lessons was sometimes challenging. Peer collaboration was facilitated through peer assessment, inquiry-based group work and experiments, aided by the use of collaborative software and combining multiple applications. Parental involvement and support contributed to student learning, although issues of equity impacted the extent to which they could engage with their children's learning, alongside gaps in family content knowledge and technological skills. Numerous implications for future policy relating to online and blended learning are provided

Characteristics of Liver Transplantation in Argentina: A Multicenter Study

Introduction: There is a lack of information regarding outcomes after liver transplant in Latin America. Objectives: This study sought to describe outcomes after liver transplant in adult patients from Argentina. Methods: We performed an ambispective cohort study of adult patients transplanted between June 2010 and October 2012 in 6 centers from Argentina. Only patients who survived after the first 48 hours postransplantation were included. Pretransplantation and posttransplantation data were collected. Results: A total of 200 patients were included in the study. Median age at time of transplant was 50 (interquartile range [IQR] 26 to 54) years. In total, 173 (86%) patients had cirrhosis, and the most frequent etiology in these patients was hepatitis C (32%). A total of 35 (17%) patients were transplanted with hepatocellular carcinoma. In patients with cirrhosis, the median Model for End-Stage Liver Disease (MELD) score at time of liver transplant was 25 (IQR 19 to 30). Median time on the waiting list for elective patients was 101 (IQR 27 to 295) days, and 3 (IQR 2 to 4) days for urgent patients. Almost 40% of the patients were readmitted during the first 6 months after liver transplant. Acute rejection occurred in 27% of the patients. Biliary and vascular complications were reported in 39 (19%) and 19 (9%) patients, respectively. Renal failure, diabetes, and dyslipidemia were present in 40 (26%), 87 (57%), and 77 (50%) at 2 years, respectively. Conclusions: We believe the information contained in this article might be of value for reviewing current practices and developing local policies.Fil: Haddad, L.. Instituto Universitario del Hospital Italiano de Buenos Aires; ArgentinaFil: Marciano, S.. Instituto Universitario del Hospital Italiano de Buenos Aires; ArgentinaFil: Cleres, M.. Fundación Favaloro; ArgentinaFil: Zerega, A.. Sanatorio Allende; ArgentinaFil: Piñero, F.. Hospital Universitario Austral; ArgentinaFil: Orozco, F.. Hospital Aleman; ArgentinaFil: Braslavsky, G.. Hospital General de Agudos Cosme Argerich; ArgentinaFil: Mendizabal, M.. Hospital Universitario Austral; ArgentinaFil: Gondolesi, Gabriel Eduardo. Fundación Favaloro; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Medicina Traslacional, Trasplante y Bioingeniería. Fundación Favaloro. Instituto de Medicina Traslacional, Trasplante y Bioingeniería; ArgentinaFil: Gil, O.. Sanatorio Allende; ArgentinaFil: Silva, M.. Hospital Universitario Austral; ArgentinaFil: Mastai, Ricardo. Hospital Aleman; ArgentinaFil: Imvertaza, O.. Hospital General de Agudos Cosme Argerich; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Medicina Traslacional, Trasplante y Bioingeniería. Fundación Favaloro. Instituto de Medicina Traslacional, Trasplante y Bioingeniería; ArgentinaFil: Descalzi, V.. Fundación Favaloro; ArgentinaFil: Gadano, A.. Instituto Universitario del Hospital Italiano de Buenos Aires; Argentin

Prediction of brain clozapine and norclozapine concentrations in humans from a scaled pharmacokinetic model for rat brain and plasma pharmacokinetics

BACKGROUND: Clozapine is highly effective in treatment-resistant schizophrenia, although, there remains significant variability in the response to this drug. To better understand this variability, the objective of this study was to predict brain extracellular fluid (ECF) concentrations and receptor occupancy of clozapine and norclozapine in human central nervous system by translating plasma and brain ECF pharmacokinetic (PK) relationships in the rat and coupling these with known human disposition of clozapine in the plasma. METHODS: Unbound concentrations of clozapine and norclozapine were measured in rat brain ECF using quantitative microdialysis after subcutaneous administration of a 10 mg/kg single dose of clozapine or norclozapine. These data were linked with plasma concentrations obtained in the same rats to develop a plasma-brain ECF compartmental model. Parameters describing brain ECF disposition were then allometrically scaled and linked with published human plasma PK to predict human ECF concentrations. Subsequently, prediction of human receptor occupancy at several CNS receptors was based on an effect model that related the predicted ECF concentrations to published concentration-driven receptor occupancy parameters. RESULTS: A one compartment model with first order absorption and elimination best described clozapine and norclozapine plasma concentrations in rats. A delay in the transfer of clozapine and norclozapine from plasma to the brain ECF compartment was captured using a transit compartment model approach. Human clozapine and norclozapine concentrations in brain ECF were simulated, and from these the median percentage of receptor occupancy of dopamine-2, serotonin-2A, muscarinic-1, alpha-1 adrenergic, alpha-2 adrenergic and histamine-1 for clozapine, and dopamine-2 for norclozapine were consistent with values reported in the literature. CONCLUSIONS: A PK model that relates clozapine and norclozapine disposition in rat plasma and brain, including blood-brain barrier transport, was developed. Using allometry and published human plasma PK, the model was successfully translated to predict clozapine and norclozapine concentrations and accordant receptor occupancy of both agents in human brain. These predicted exposure and occupancy measures at several receptors that bind clozapine may be employed to extend our understanding of clozapine's complex behavioral effects in humans

Identification of Proteins Associated with the Formation of Oral Biofilms

Objective: To identify proteins associated with the formation of Streptococcus gordonii and Fusobacterium nucleatum biofilms. Material and Methods: Biofilms composed of two bacterial species, S. gordonii and F. nucleatum, were cultured for 1, 4, 7, and 10 days. The presence of both species was confirmed via amplification of the srtA and radD genes using real-time PCR. The concentrations of proteins associated with the biofilms and individual species were quantified using Western blotting. Results: The protein profiles of S. gordonii and F. nucleatum from individual cultures determined using one-dimensional electrophoresis revealed proteins found in S. gordonii and in F. nucleatum. Ct and reciprocal Ct values were determined for the exposed S. gordonii and F. nucleatum biofilms. Glyceraldehyde 3-phosphate dehydrogenase (GAPDH) protein was detected in biofilms and F. nucleatum, whereas HSP40 protein was present only in biofilms after 7 and 10 days of formation. Conclusion: HSP40 was detected only in the formed biofilms; thus, HSP40 is an essential proteins for adhesion

Metodología de análisis de complejidad de Procedimientos de Operación de Emergencia de Centrales Nucleares

Los Procedimientos de Operación de Emergencia (POE) establecen las etapas y contienen las acciones a ejecutar por parte de un operador para dar respuesta a una situación de emergencia. Actualmente se están desarrollando metodologías que permitan evaluar aspectos tales como la complejidad, la completitud y la vulnerabilidad de dichos procedimientos. En la presente ponencia se presenta una metodología para elaborar la red topológica de un POE y un análisis de la misma centrado en la complejidad como atributo fundamental.Martorell Aigües, P.; Martorell Alsina, SS.; Marton Lluch, I.; Pelayo, F.; Mendizabal, R. (2013). Metodología de análisis de complejidad de Procedimientos de Operación de Emergencia de Centrales Nucleares. Sociedad Nuclear Española. http://hdl.handle.net/10251/71614

Back-to-back azimuthal correlations in Z+jet events at high transverse momentum in the TMD parton branching method at next-to-leading order

Azimuthal correlations in Z+jet production at large transverse momenta are computed by matching Parton - Branching (PB) TMD parton distributions and showers with NLO calculations via MCatNLO. The predictions are compared with those for dijet production in the same kinematic range. The azimuthal correlations $\Delta\phi$ between the Z boson and the leading jet are steeper compared to those in dijet production at transverse momenta ${\cal O}(100)$ GeV , while they become similar for very high transverse momenta ${\cal O}(1000)$ GeV. The different patterns of Z+jet and dijet azimuthal correlations can be used to search for potential factorization - breaking effects in the back-to-back region, which depend on the different color and spin structure of the final states and their interferences with the initial states. In order to investigate these effects experimentally, we propose to measure the ratio of the distributions in $\Delta\phi$ for Z+jet - and multijet production at low and at high transverse momenta, and compare the results to predictions obtained assuming factorization. We examine the role of theoretical uncertainties by performing variations of the factorization scale, renormalization scale and matching scale. In particular, we present a comparative study of matching scale uncertainties in the cases of PB -TMD and collinear parton showers

Impact of metabolic comorbidity on the association between body mass index and heatlh-related quality of life: a Scotland-wide cross-sectional study of 5,608 participants

<p/>Background: The prevalence of obesity is rising in Scotland and globally. Overall, obesity is associated with increased morbidity, mortality and reduced health-related quality of life. Studies suggest that "healthy obesity" (obesity without metabolic comorbidity) may not be associated with morbidity or mortality. Its impact on health-related quality of life is unknown. <p/>Methods: We extracted data from the Scottish Health Survey on self-reported health-related quality of life, body mass index (BMI), demographic information and comorbidity. SF-12 responses were converted into an overall health utility score. Linear regression analyses were used to explore the association between BMI and health utility, stratified by the presence or absence of metabolic comorbidity (diabetes, hypertension, hypercholesterolemia or cardiovascular disease), and adjusted for potential confounders (age, sex and deprivation quintile). <p/>Results: Of the 5,608 individuals, 3,744 (66.8%) were either overweight or obese and 921 (16.4%) had metabolic comorbidity. There was an inverted U-shaped relationship whereby health utility was highest among overweight individuals and fell with increasing BMI. There was a significant interaction with metabolic comorbidity (p = 0.007). Individuals with metabolic comorbidty had lower utility scores and a steeper decline in utility with increasing BMI (morbidly obese, adjusted coefficient: -0.064, 95% CI -0.115, -0.012, p = 0.015 for metabolic comorbidity versus -0.042, 95% CI -0.067, -0.018, p = 0.001 for no metabolic comorbidity). <p/>Conclusions: The adverse impact of obesity on health-related quality of life is greater among individuals with metabolic comorbidity. However, increased BMI is associated with reduced health-related quality of life even in the absence of metabolic comorbidity, casting doubt on the notion of "healthy obesity"

Desarrollo y Aplicación de una Metodología CSAU para el Caso de un ATWS en un BWR utilizando Métodos de Teoría de la Información

Se ha desarrollado una metodología tipo CSAU utilizando herramientas de teoría de la información para evaluar la incertidumbre en los parámetros de entrada y de los modelos que pueden afectar al parámetro crítico de seguridad (PCS). Para ello se han desarrollado dos herramientas auxiliares los programas GEDIPA-V1 y UNTHERCO –V1, el primero averigua la distribución de un parámetro o parámetros utilizando teoría de la información y evalúa también los momentos de la distribución con sus intervalos de confianza a partir de los datos. Mientras que el segundo realiza el muestreo por MONTECARLO de los parámetros de entrada cuya importancia ha sido puesta de manifiesto previamente mediante el PIRT y el análisis de sensibilidad. En el caso de que la información sobre un parámetro sea incompleta se aplica el principio de la máxima entropía o el de la máxima entropía relativa para obtener su función de distribución. La metodología se ha aplicado a la C.N. de Cofrentes para determinar el valor del Parámetro Crítico de Seguridad de un ATWS con un 95/95 de cubrimiento y confianza.Muñoz-Cobo González, JL.; Escrivá Castells, FA.; Mendizabal, R.; Pelayo, F.; Melara San Román, J. (2013). Desarrollo y Aplicación de una Metodología CSAU para el Caso de un ATWS en un BWR utilizando Métodos de Teoría de la Información. Sociedad Nuclear Española. http://hdl.handle.net/10251/71591