Time representation in reinforcement learning models of the basal ganglia

Reinforcement learning (RL) models have been influential in understanding many aspects of basal ganglia function, from reward prediction to action selection. Time plays an important role in these models, but there is still no theoretical consensus about what kind of time representation is used by the basal ganglia. We review several theoretical accounts and their supporting evidence. We then discuss the relationship between RL models and the timing mechanisms that have been attributed to the basal ganglia. We hypothesize that a single computational system may underlie both RL and interval timing—the perception of duration in the range of seconds to hours. This hypothesis, which extends earlier models by incorporating a time-sensitive action selection mechanism, may have important implications for understanding disorders like Parkinson's disease in which both decision making and timing are impaired

An intergenerational programme delays health impairment in nursing home residents: the Duplo project

Purpose To analyse whether an intergenerational programme in which students interacted with institutionalised older persons had any impact on the older persons’ functional status. Methods Each academic year, a group of older adults living in nursing homes were divided into two arms. For the next four months, the first group received daily visits from a group of students during which they followed a pre-established activity plan, whilst the other arm proceeded with their normal activity. After 4 months, the groups crossed over, and the second arm received the student visits, whilst the first group returned to their normal activity. A battery of tests was performed at inception, crossover and the end of the second period. The tests explored mobility (Timed Up-and-Go), cognition (Mini-Mental Examination), executive function (Frontal Assessment Battery) and mood (Geriatric Depression Scale). A dichotomous aggregate “significant impairment” variable was deemed to be present when there was at least a 20% loss of function (compared to the value at the beginning of the period) in any of the aforementioned tests. Results The study included 289 older adults who visited with 91 students. Subjects in the active phase had a lower incidence of significant impairment than those in the control phase (O.R. 0.90, p < 0.01). There were no significant differences in the individual variables.post-print900 K

Análisis de necesidades formativas de gerentes del sector turístico: una aproximación cualitativa

Las organizaciones de servicios de naturaleza turística son de suma importancia para la economía española y en concreto también para el desarrollo socioeconómico de la Comunidad Valenciana. Los usuarios de estos servicios exigen de forma creciente mayores estándares de calidad, lo que obliga al negocio turístico a realizar un importante esfuerzo de adecuación, modernización y especialización. En este contexto, la figura del gerente de las organizaciones turísticas resulta de suma importancia para el funcionamiento de la empresa, de ahí la necesidad de que su formación sea adecuada para desempeñar su puesto de trabajo y responder eficazmente a las exigencias de calidad del servicio y satisfacción de los usuarios. Sin embargo, la formación de los gerentes no es siempre la adecuada y, en muchas ocasiones, no se analiza exactamente qué actividades formativas necesitan estos gerentes para desempeñar adecuadamente su puesto de trabajo y ofrecer un servicio de calidad. Por ello, el objetivo de este trabajo es analizar las necesidades de formación de los gerentes del sector turístico de la Comunidad Valenciana. Se ha utilizado como metodología el análisis cualitativo de la información obtenida en cuatro grupos de discusión, conformados por expertos del sector y gerentes de hoteles y restaurantes. Los resultados ponen de manifiesto la existencia de importantes necesidades de formación en los gerentes, tanto para realizar adecuadamente las tareas de su puesto actual, como para afrontar de forma óptima los cambios que pueden darse en dicho puesto en el futuro. Este estudio presenta como innovación el uso de una metodología cualitativa como herramienta útil para diagnosticar necesidades formativas a distintos niveles de análisis

Métodos objetivos de estimación del contenido de azúcares añadidos en alimentos, para su declaración en la Información Nutricional Obligatoria y etiquetado frontal en Argentina

A partir de la exigencia de etiquetado frontal y declaración del contenido de azúcares totales y añadidos en la información nutricional obligatoria de alimentos envasados y bebidas analcohólicas, se torna necesario disponer de las herramientas analíticas adecuadas para la determinación de los azúcares añadidos a los mismos, tanto para su declaración por los elaboradores, como para uso de los organismos de control. Ya que los métodos analíticos, tanto químicos como instrumentales no permiten discriminar entre azúcares naturales y añadidos, el objetivo del trabajo es ofrecer una metodología adecuada para la estimación del contenido de azúcares añadidos, según la definición de la reglamentación vigente argentina, que permita obtener resultados seguros, confiables y dentro del margen de tolerancias establecido. Para su logro, se propone el uso de cálculos de balances de materia basados en el contenido de azúcares totales y otros parámetros determinados analíticamente y en tablas de composición que discriminen contenido de azúcares para frutas y hortalizas. Los métodos propuestos resultan aplicables en conservas de frutas, yogur y otras leches fermentadas, confituras como mermeladas, dulces, frutas en almíbar y confitadas, etc., y dulce de leche

Differentiation of Symbiotic Cells and Endosymbionts in Medicago truncatula Nodulation Are Coupled to Two Transcriptome-Switches

The legume plant Medicago truncatula establishes a symbiosis with the nitrogen-fixing bacterium Sinorhizobium meliloti which takes place in root nodules. The formation of nodules employs a complex developmental program involving organogenesis, specific cellular differentiation of the host cells and the endosymbiotic bacteria, called bacteroids, as well as the specific activation of a large number of plant genes. By using a collection of plant and bacterial mutants inducing non-functional, Fix− nodules, we studied the differentiation processes of the symbiotic partners together with the nodule transcriptome, with the aim of unravelling links between cell differentiation and transcriptome activation. Two waves of transcriptional reprogramming involving the repression and the massive induction of hundreds of genes were observed during wild-type nodule formation. The dominant features of this “nodule-specific transcriptome” were the repression of plant defense-related genes, the transient activation of cell cycle and protein synthesis genes at the early stage of nodule development and the activation of the secretory pathway along with a large number of transmembrane and secretory proteins or peptides throughout organogenesis. The fifteen plant and bacterial mutants that were analyzed fell into four major categories. Members of the first category of mutants formed non-functional nodules although they had differentiated nodule cells and bacteroids. This group passed the two transcriptome switch-points similarly to the wild type. The second category, which formed nodules in which the plant cells were differentiated and infected but the bacteroids did not differentiate, passed the first transcriptome switch but not the second one. Nodules in the third category contained infection threads but were devoid of differentiated symbiotic cells and displayed a root-like transcriptome. Nodules in the fourth category were free of bacteria, devoid of differentiated symbiotic cells and also displayed a root-like transcriptome. A correlation thus exists between the differentiation of symbiotic nodule cells and the first wave of nodule specific gene activation and between differentiation of rhizobia to bacteroids and the second transcriptome wave in nodules. The differentiation of symbiotic cells and of bacteroids may therefore constitute signals for the execution of these transcriptome-switches

BRCA1 polymorphism in breast cancer patients from Argentina

Breast cancer is the most common type of cancer in females in Argentina, with an incidence rate similar to that in the USA. However, the contribution of the BRCA1 or BRCA2 mutation in breast cancer incidence has not yet been investigated in Argentina. In order to evaluate which BRCA1 polymorphisms or mutations characterize female breast cancer in Argentina, the current study enrolled 206 females with breast cancer from several hospitals from the southeast of Argentina. A buccal smear sample was obtained in duplicate from each patient and the DNA samples were processed for polymorphism analysis using the single-strand conformational polymorphism technique. The polymorphisms in BRCA1 were investigated using a combination of 15 primers to analyze exons 2, 3, 5, 20 and 11 (including the 11.1 to 11.12 regions). The BRCA1 mutations were confirmed by direct sequencing. Samples were successfully examined from 154 females and, among these, 16 mutations were identified in the BRCA1 gene representing 13.9% of the samples analyzed. One patient was identified with a polymorphism in exon 2 (0.86%), four in exon 20 (3.48%), four in exon 11.3 (3.48%), one in exon 11.7 (0.86%), two in exon 11.8 (1.74%), one in exon 11.10 (0.86%) and one in exon 11.11 (0.86%). The most prevalent alteration in BRCA1 was located in exon 11 (11 out of 16 patients; 68.75%). The objective of our next study is to evaluate the prevalence of mutations in the BRCA2 gene and analyze the BRCA1 gene in the healthy relatives of BRCA1 mutation carriers.Fil: Jaure, Omar David Argentino. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Bahía Blanca. Centro de Recursos Naturales Renovables de la Zona Semiárida. Universidad Nacional del Sur. Centro de Recursos Naturales Renovables de la Zona Semiárida; ArgentinaFil: Alonso, Eliana Noelia. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Bahía Blanca. Centro de Recursos Naturales Renovables de la Zona Semiárida. Universidad Nacional del Sur. Centro de Recursos Naturales Renovables de la Zona Semiárida; ArgentinaFil: Aguilera Braico, Diego Máximo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Bahía Blanca. Centro de Recursos Naturales Renovables de la Zona Semiárida. Universidad Nacional del Sur. Centro de Recursos Naturales Renovables de la Zona Semiárida; ArgentinaFil: Nieto, Alvaro. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Bahía Blanca. Centro de Recursos Naturales Renovables de la Zona Semiárida. Universidad Nacional del Sur. Centro de Recursos Naturales Renovables de la Zona Semiárida; ArgentinaFil: Orozco, Manuela. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Bahía Blanca. Centro de Recursos Naturales Renovables de la Zona Semiárida. Universidad Nacional del Sur. Centro de Recursos Naturales Renovables de la Zona Semiárida; ArgentinaFil: Morelli, Cecilia. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Bahía Blanca. Centro de Recursos Naturales Renovables de la Zona Semiárida. Universidad Nacional del Sur. Centro de Recursos Naturales Renovables de la Zona Semiárida; ArgentinaFil: Ferro, Alejandro M.. Hospital Italiano; ArgentinaFil: Barutta, Elena. Medifem; ArgentinaFil: Vincent, Esteban. Medifem; ArgentinaFil: Martínez, Domingo. Provincia de Buenos Aires. Ministerio de Salud. Hospital Municipal de Agudos Dr. Leónidas Lucero; ArgentinaFil: Martínez, Ignacio. Provincia de Buenos Aires. Ministerio de Salud. Hospital Municipal de Agudos Dr. Leónidas Lucero; ArgentinaFil: Maegli, Maria Ines. Provincia de Buenos Aires. Ministerio de Salud. Hospital Municipal de Agudos Dr. Leónidas Lucero; ArgentinaFil: Frizza, Alejandro. Medifem; ArgentinaFil: Kowalyzyn, Ruben. Clínica Viedma; ArgentinaFil: Salvadori, Marisa. Hospital Dr. Lucio Molas; ArgentinaFil: Ginestet, Paul. Provincia de Buenos Aires. Ministerio de Salud. Hospital y Maternidad Municipal Pigüé; ArgentinaFil: Gonzalez Donna, Maria L.. Hospital Italiano; ArgentinaFil: Balogh, Gabriela Andrea. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Bahía Blanca. Centro de Recursos Naturales Renovables de la Zona Semiárida. Universidad Nacional del Sur. Centro de Recursos Naturales Renovables de la Zona Semiárida; Argentin

Dynamics of African swine fever virus (ASFV) infection in domestic pigs infected with virulent, moderate virulent and attenuated genotype II ASFV European isolates

This study aimed to compare the infection dynamics of three genotype II African swine fever viruses (ASFV) circulating in Europe. Eighteen domestic pigs divided into three groups were infected intramuscularly or by direct contact with two haemadsorbent ASFVs (HAD) from Poland (Pol16/DP/ OUT21) and Estonia (Est16/WB/Viru8), and with the Latvian non-HAD ASFV (Lv17/WB/Rie1). Parameters, such as symptoms, pathogenicity, and distribution of the virus in tissues, humoral immune response, and dissemination of the virus by blood, oropharyngeal and rectal routes, were investigated. The Polish ASFV caused a case of rapidly developing fatal acute disease, while the Estonian ASFV caused acute to sub-acute infections and two animals survived. In contrast, animals infected with the ASFV from Latvia developed a more subtle, mild, or even subclinical disease. Oral excretion was sporadic or even absent in the attenuated group, whereas in animals that developed an acute or sub-acute form of ASF, oral excretion began at the same time the ASFV was detected in the blood, or even 3 days earlier, and persisted up to 22 days. Regardless of virulence, blood was the main route of transmission of ASFV and infectious virus was isolated from persistently infected animals for at least 19 days in the attenuated group and up to 44 days in the group of moderate virulence. Rectal excretion was limited to the acute phase of infection. In terms of diagnostics, the ASFV genome was detected in contact pigs from oropharyngeal samples earlier than in blood, independently of virulence. Together with blood, both samples could allow to detect ASFV infection for a longer period. The results presented here provide quantitative data on the spread and excretion of ASFV strains of different virulence among domestic pigs that can help to better focus surveillance activities and, thus, increase the ability to detect ASF introductions earlier.This study was supported by the INIA (Projects RTA2015-00033-C02-01, AT2015-002) and the European Union Reference laboratory for ASF (Grant no.: UE- LR PPA/03). We would like to thank all the staff at the INIA-CISA who worked in the animal facilities department.Peer reviewe

Dystrophinopathy Phenotypes and Modifying Factors in Exon 45-55 Deletion

Duchenne muscular dystrophy (DMD) exon 45-55 deletion (del45-55) has been postulated as a model that could treat up to 60% of DMD patients, but the associated clinical variability and complications require clarification. We aimed to understand the phenotypes and potential modifying factors of this dystrophinopathy subset. This cross-sectional, multicenter cohort study applied clinical and functional evaluation. Next generation sequencing was employed to identify intronic breakpoints and their impact on the Dp140 promotor, intronic long noncoding RNA, and regulatory splicing sequences. DMD modifiers (SPP1, LTBP4, ACTN3) and concomitant mutations were also assessed. Haplotypes were built using DMD single nucleotide polymorphisms. Dystrophin expression was evaluated via immunostaining, Western blotting, reverse transcription polymerase chain reaction (PCR), and droplet digital PCR in 9 muscle biopsies. The series comprised 57 subjects (23 index) expressing Becker phenotype (28%), isolated cardiopathy (19%), and asymptomatic features (53%). Cognitive impairment occurred in 90% of children. Patients were classified according to 10 distinct index-case breakpoints; 4 of them were recurrent due to founder events. A specific breakpoint (D5) was associated with severity, but no significant effect was appreciated due to the changes in intronic sequences. All biopsies showed dystrophin expression of >67% and traces of alternative del45-57 transcript that were not deemed pathogenically relevant. Only the LTBP4 haplotype appeared associated the presence of cardiopathy among the explored extragenic factors. We confirmed that del45-55 segregates a high proportion of benign phenotypes, severe cases, and isolated cardiac and cognitive presentations. Although some influence of the intronic breakpoint position and the LTBP4 modifier may exist, the pathomechanisms responsible for the phenotypic variability remain largely unresolved. ANN NEUROL 2022;92:793-80