High precision symplectic integrators for the Solar System

Using a Newtonian model of the Solar System with all 8 planets, we perform extensive tests on various symplectic integrators of high orders, searching for the best splitting scheme for long term studies in the Solar System. These comparisons are made in Jacobi and heliocentric coordinates and the implementation of the algorithms is fully detailed for practical use. We conclude that high order integrators should be privileged, with a preference for the new (10, 6, 4) method of Blanes et al. (2013). © 2013 Springer Science+Business Media Dordrecht.This work was supported by GTSNext project. The work of SB, FC, JM and AM has been partially supported by Ministerio de Ciencia e Innovacion (Spain) under project MTM2010-18246-C03 (co-financed by FEDER Funds of the European Union).Farrés, A.; Laskar, J.; Blanes Zamora, S.; Casas Perez, F.; Makazaga, J.; Murua, A. (2013). High precision symplectic integrators for the Solar System. 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Primeros resultados de los trabajos arqueológicos en el lago Colhué Huapi (Chubut)

El objetivo general del proyecto de investigación, iniciado en 2005, es el estudio de los procesos de diversificación económica en poblaciones cazadoras recolectoras de Patagonia Central. Generalmente se considera que estos grupos basaron su economía casi exclusivamente en la caza del guanaco (Lama guanicoe); sin embargo, creemos que la economía de estos grupos pudo haber sido más diversificada en momentos y ambientes (o microambientes) particulares, como es el caso de los sistemas lacustres. (...)Fil: Moreno, Julian Eduardo. Universidad Nacional de la Patagonia ; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Nacional Patagónico; ArgentinaFil: Perez Ruiz, Hugo Gabriel. Universidad Nacional de la Patagonia ; ArgentinaFil: Ramirez Rozzi, Fernando. Centre National de la Recherche Scientifique; FranciaFil: Reyes, Mariano Rodolfo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Nacional Patagónico; ArgentinaFil: Svoboda, Ariadna. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Centro Nacional Patagónico. Instituto de Diversidad y Evolución Austral; ArgentinaFil: Peralta Gonzalez, Santiago. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Nacional Patagónico; ArgentinaFil: Herrera Santana, Misael. Universidad Nacional de la Patagonia ; Argentin

Epidemiological investigation of bovine tuberculosis herd breakdowns in Spain 2009/2011

We analyzed the most likely cause of 687 bovine tuberculosis (bTB) breakdowns detected in Spain between 2009 and 2011 (i.e., 22% of the total number of breakdowns detected during this period). Seven possible causes were considered: i) residual infection; ii) introduction of infected cattle from other herds; iii) sharing of pastures with infected herds; iv) contiguous spread from infected neighbor herds; v) presence of infected goats in the farm; vi) interaction with wildlife reservoirs and vii) contact with an infected human. For each possible cause a decision tree was developed and key questions were included in each of them. Answers to these key questions lead to different events within each decision tree. In order to assess the likelihood of occurrence of the different events a qualitative risk assessment approach was used. For this purpose, an expert opinion workshop was organized and ordinal values, ranging from 0 to 9 (i.e., null to very high likelihood of occurrence) were assigned. The analysis identified residual infection as the most frequent cause of bTB breakdowns (22.3%; 95%CI: 19.4-25.6), followed by interaction with wildlife reservoirs (13.1%; 95%CI: 10.8-15.8). The introduction of infected cattle, sharing of pastures and contiguous spread from infected neighbour herds were also identified as relevant causes. In 41.6% (95%CI: 38.0-45.4) of the breakdowns the origin of infection remained unknown. Veterinary officers conducting bTB breakdown investigations have to state their opinion about the possible cause of each breakdown. Comparison between the results of our analysis and the opinion from veterinary officers revealed a slight concordance. This slight agreement might reflect a lack of harmonized criteria to assess the most likely cause of bTB breakdowns as well as different perceptions about the importance of the possible causes. This is especially relevant in the case of the role of wildlife reservoirs

Community Strategy for Hepatitis B, C, and D Screening and Linkage to Care in Mongolians Living in Spain

Mongolian community; Community program; Viral hepatitis screeningComunidad mongola; Programa comunitario; Cribado de hepatitis viralComunitat mongol; Programa comunitari; Cribatge de hepatitis viralMongolia has one of the highest viral hepatitis infection (B, C, and D) rates in the world. The aims of this study were to increase awareness of this disease and promote viral hepatitis screening in the Mongolian community living in Spain. Through a native community worker, Mongolian adults were invited to a community program consisting of an educational activity, an epidemiological questionnaire, and rapid point-of-care testing for hepatitis B and C. In those testing positive, blood extraction was performed to determine serological and virological parameters. In total, 280 Mongolians were invited to the program and 222 (79%) attended the event: 139 were women (63%), mean age was 42 years, and 78 (35%) had viral hepatitis risk factors. Testing found 13 (5.8%) anti-HCV-positive individuals, 1 with detectable HCV RNA (0.5%), 8 HBsAg-positive (3.6%), and 7 with detectable HBV DNA (3.1%). One additional individual had HBV/HCV co-infection with detectable HBV DNA and HCV RNA. Two subjects had hepatitis B/D co-infection (0.9%). The knowledge questionnaire showed a 1.64/8-point (20.5%) increase in correct answers after the educational activity. In summary, a viral hepatitis community program was feasible and widely accepted. It increased awareness of this condition in the Mongolian community in Spain and led to linkage to care in 22 participants, 50% of whom were unaware of their infection.This project was funded by GILEAD SCIENCES (GLD21/00139)

The challenge of the laboratory diagnosis in a confirmed congenital Zika virus syndrome in utero: A case report

Zika virus; Diagnosis; Infection in uteroVirus Zika; Diagnòstic; Infecció uterinaVirus Zika; Diagnóstico; Infección uterinaINTRODUCTION: Zika virus (ZIKV) has caused one of the most challenging global infectious epidemics in recent years because of its causal association with severe microcephaly and other congenital malformations. The diagnosis of viral infections usually relies on the detection of virus proteins or genetic material in clinical samples as well as on the infected host immune responses. Serial serologic testing is required for the diagnosis of congenital infection when diagnostic molecular biology is not possible. PATIENT CONCERNS: A 2-year-old girl, born to a mother with confirmed ZIKV infection during pregnancy, with a confirmed ZIKV infection in utero, showed at birth a severe microcephaly and clinical characteristics of fetal brain disruption sequence compatible with a congenital ZIKV syndrome (CZS). DIAGNOSIS: ZIKV-RNA and ZIKV-IgM serological response performed at birth and during the follow-up time tested always negative. Serial serologic ZIKV-IgG tests were performed to assess the laboratory ZIKV diagnosis, ZIKV-IgG seroreversion was observed at 21 months of age. ZIKV diagnosis of this baby had to be relied on her clinical and radiological characteristics that were compatible with a CZS. INTERVENTIONS: The patient was followed-up as per protocol at approximately 1, 4, 9, 12, 18-21, and 24 months of age. Neurological, radiological, audiological, and ophthalmological assessment were performed during this period of time. Prompt rehabilitation was initiated to prevent potential adverse long-term neurological outcomes. OUTCOMES: The growth of this girl showed a great restriction at 24 months of age with a weight of 8.5 kg (-2.5 z-score) and a head circumference of 40.5 cm (-4.8 z-score). She also had a great neurodevelopmental delay at the time of this report. CONCLUSION: We presume that as a consequence of prenatal ZIKV infection, the fetal brain and other organs are damaged before birth through direct injury. Following this, active infection ends during intrauterine life, and as a consequence the immune system of the infant is unable to build up a consistent immune response thereafter. Further understanding of the mechanisms taking part in the pathogenesis of ZIKV congenital infection is needed. This finding might change our paradigm regarding serological response in the ZIKV congenital infection

Allogeneic Hematopoietic Stem Cell Transplantation in Transformed Follicular Lymphoma (tFL): Results of a Retrospective Multicenter Study from GELTAMO/GETH-TC Spanish Groups

Simple Summary Follicular lymphoma (FL) is the most prevalent subtype of indolent lymphoma, accounting for 70% of all cases. The estimated risk of histological transformation (tFL), such as diffuse large B cell lymphoma (DLBCL), varies from 2-3% per year to 7-8% at 10 years in different series. Treatment after transformation is not clearly established. Allogeneic hematopoietic stem cell transplantation (alloSCT) could be an option for these patients, but it has not been widely explored. We analyze the efficacy and toxicity of alloSCT in 43 patients from 14 Spanish centers. We observed long-term survival in around one third of the patients, especially those who developed chronic graft versus host disease, indicating that alloSCT continues to be a potentially curative option for patients with tFL, mainly due to the graft versus lymphoma effect. Background: Transformation of follicular lymphoma into an aggressive lymphoma (tFL) worsens the prognosis and the standard treatment is not completely defined. Allogeneic hematopoietic stem cell transplantation (alloSCT) could be a potentially curative option for these patients, but it has not been widely explored. Methods: We designed a retrospective multicenter study to analyze the efficacy and toxicity of alloSCT in tFL patients and potential prognostic factors of survival. Results: A total of 43 patients diagnosed with tFL who underwent alloSCT in 14 Spanish centers between January 2000 and January 2019 were included. Median age was 44 (31-67) years. After a median follow-up of 58 months, estimated 5-year overall survival (OS) and progression-free survival (PFS) were both 35%. Estimated 100-day and 1-year non-relapse mortality (NRM) were 20% and 34%, respectively. The type of conditioning regimen (3-year OS of 52% vs. 20%, respectively, for reduced-intensity vs. myeloablative conditioning) and development of chronic graft versus host disease (cGVHD) (3-year OS of 75% vs. 40%) were the only factors significantly associated with OS. The only variable with an independent association with OS was cGVHD (HR, 3.4; 95% CI, 1.2-9.6). Conclusions: Our results indicate that alloSCT continues to be a potentially curative option for patients with tFL

Implantació i Millora de l'European Project Semester (EPS) a l'EPSEVG

L'EPSEVG de la UPC va implantar l’European Project Semester (EPS) un programa formatiu innovador que respon a les demandes plantejades per la societat i l’Espai Europeu d’Ensenyament Superior (EEES) durant el curs 2007‐2008. L’EPS permet cobrir la demanda d’estudiants estrangers que volen venir a estudiar a l’escola, demanda, que, a nivell de grau en enginyeria no esta coberta en cap universitat catalana.L’EPS també és una oportunitat per augmentar el compromís de l’EPSEVG vers la sostenibilitat. El programa s’ha ambientalitzat d’acord amb les directrius del Pla UPC Sostenible 2015 essent la sostenibilitat un dels eixos transversals que li dona contingut i que identifica a tots els projectes desenvolupats. A més de la sostenibilitat, el programa inclou altres matèries transversals (com ara, la innovació, la gestió de projectes, l’accessibilitat...). L’EPS utilitza el model d’aprenentatge basat en projectes (Project Based Learning), i hi introdueix dos components nous: la docència en anglès i la interculturalitat dins de l’aula. Les noves tecnologies s’utilitzen tant per dinamitzar el treball dels grups com per facilitar el seu aprenentatge, doncs l’EPS inclou tallers i seminaris en la modalitat semipresencial.Peer Reviewe

Characteristics of 24 SARS-CoV-2-Sequenced Reinfection Cases in a Tertiary Hospital in Spain

SARS-CoV-2; Clinical features; ReinfectionSARS-CoV-2; Características clínicas; ReinfecciónSARS-CoV-2; Característiques clíniques; ReinfeccióBackground: Since the emergence of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), the main concern is whether reinfections are possible, and which are the associated risk factors. This study aims to describe the clinical and molecular characteristics of 24 sequence-confirmed reinfection SARS-CoV-2 cases over 1 year in Barcelona (Catalonia, Spain). Methods: Patients with > 45 days between two positive PCR tests regardless of symptoms and negative tests between episodes were initially considered as suspected reinfection cases from November 2020 to May 2021. Whole-genome sequencing (WGS) was performed to confirm genetic differences between consensus sequences and for phylogenetic studies based on PANGOLIN nomenclature. Reinfections were confirmed by the number of mutations, change in lineage, or epidemiological criteria. Results: From 39 reported suspected reinfection cases, complete viral genomes could be sequenced from both episodes of 24 patients, all were confirmed as true reinfections. With a median age of 44 years (interquartile range [IQR] 32–65), 66% were women and 58% were healthcare workers (HCWs). The median days between episodes were 122 (IQR 72–199), occurring one-third within 3 months. Reinfection episodes were frequently asymptomatic and less severe than primary infections. The absence of seroconversion was associated with symptomatic reinfections. Only one case was reinfected with a variant of concern (VOC). Conclusion: Severe acute respiratory syndrome coronavirus 2 reinfections can occur in a shorter time than previously reported and are mainly found in immunocompetent patients. Surveillance through WGS is useful to identify viral mutations associated with immune evasion.This research was supported by CIBER -Consorcio Centro de Investigación Biomédica en Red- (CB 2021), Instituto de Salud Carlos III, Ministerio de Ciencia e Innovación and Unión Europea – NextGenerationEU

A year living with SARS-CoV-2: an epidemiological overview of viral lineage circulation by whole-genome sequencing in Barcelona city (Catalonia, Spain)

Catalonia; SARS-CoV-2; Molecular epidemiologyCataluña; SARS-CoV-2; Epidemiología molecularCatalunya; SARS-CoV-2; Epidemiologia molecularHerein, we describe the genetic diversity of circulating SARS-CoV-2 viruses by whole-genome sequencing (WGS) in Barcelona city (Catalonia, Spain) throughout the first four pandemic waves. From weeks 11/2020–24/2021, SARS-CoV-2-positive respiratory samples were randomly selected per clinical setting (80% from primary care or 20% from the hospital), age group, and week. WGS was performed following the ARTICv3 protocol on MiSeq or NextSeq2000 Illumina platforms. Nearly complete consensus sequences were used for genetic characterization based on GISAID and PANGOLIN nomenclatures. From 2475 samples, 2166 (87%) were fully sequenced (78% from primary care and 22% from hospital settings). Multiple genetic lineages were co-circulating, but four were predominant at different periods. While B.1.5 (50.68%) and B.1.1 (32.88%) were the major lineages during the first pandemic wave, B.1.177 (66.85%) and B.1.1.7 (83.80%) were predominant during the second, third, and fourth waves, respectively. Almost all (96.4%) were carrying D614G mutation in the S protein, with additional mutations that define lineages or variants. But some mutations of concern, such as E484K from B.1.351 and P.1 lineages are currently under monitoring, together with those observed in the receptor-binding domain or N-terminal domain, such as L452R and T478K from B.1.617.2 lineage. The fact that a predominant lineage was observed in each pandemic wave suggests advantageous properties over other contemporary co-circulating variants. This genetic variability should be monitored, especially when a massive vaccination campaign is ongoing because the potential selection and emergence of novel antigenic SARS-CoV-2 strains related to immunological escapement events.This work was supported by Spanish Network for the Research in Infectious Diseases: [Grant Number REIPI RD16/0016/0003]; Centro para el Desarrollo Tecnológico Industrial (CDTI) from the Spanish Ministry of Economy and Business [Grant Number IDI-20200297]; Direcció General de Recerca i Innovació en Salut (DGRIS); European Development Regional Fund (ERDF) “A way to achieve Europe” by Spanish Network for Research in Infectious Diseases [REIPI RD16/0016/0003]

Allogeneic Stem Cell Transplantation in Mantle Cell Lymphoma; Insights into Its Potential Role in the Era of New Immunotherapeutic and Targeted Therapies: The GETH/GELTAMO Experience

Allo-SCT is a curative option for selected patients with relapsed/refractory (R/R) MCL, but with significant NRM. We present the long-term results of patients receiving allo-SCT in Spain from March 1995 to February 2020. The primary endpoints were EFS, OS, and cumulative incidence (CI) of NRM, relapse, and GVHD. We included 135 patients, most (85%) receiving RIC. After a median follow-up of 68 months, 5-year EFS and OS were 47 and 50%, respectively. Overall and CR rates were 86 and 80%. The CI of relapse at 1 and 3 years were 7 and 12%. NRM at day 100 and 1 year were 17 and 32%. Previous ASCT and Grade 3-4 aGVHD were associated with a higher NRM. Grade 3-4 aGVHD, donor type (mismatch non-related), and the time-period 2006-2020 were independently related to worse EFS. Patients from 1995-2005 were younger, most from HLA-identical sibling donors, and were pretreated less. Our data confirmed that allo-SCT may be a curative option in R/R MCL with low a CI of relapse, although NRM is still high, being mainly secondary to aGVHD. The arrival of new, highly effective and low toxic immunotherapeutic or targeted therapies inevitably will relegate allo-SCT to those fit patients who fail these therapies, far away from the optimal timing of treatment