Information flow through a model of the C. elegans klinotaxis circuit

Understanding how information about external stimuli is transformed into behavior is one of the central goals of neuroscience. Here we characterize the information flow through a complete sensorimotor circuit: from stimulus, to sensory neurons, to interneurons, to motor neurons, to muscles, to motion. Specifically, we apply a recently developed framework for quantifying information flow to a previously published ensemble of models of salt klinotaxis in the nematode worm C. elegans. The models are grounded in the neuroanatomy and currently known neurophysiology of the worm. The unknown model parameters were optimized to reproduce the worm's behavior. Information flow analysis reveals several key principles underlying how the models operate: (1) Interneuron class AIY is responsible for integrating information about positive and negative changes in concentration, and exhibits a strong left/right information asymmetry. (2) Gap junctions play a crucial role in the transfer of information responsible for the information symmetry observed in interneuron class AIZ. (3) Neck motor neuron class SMB implements an information gating mechanism that underlies the circuit's state-dependent response. (4) The neck carries non-uniform distribution about changes in concentration. Thus, not all directions of movement are equally informative. Each of these findings corresponds to an experimental prediction that could be tested in the worm to greatly refine our understanding of the neural circuit underlying klinotaxis. Information flow analysis also allows us to explore how information flow relates to underlying electrophysiology. Despite large variations in the neural parameters of individual circuits, the overall information flow architecture circuit is remarkably consistent across the ensemble, suggesting that information flow analysis captures general principles of operation for the klinotaxis circuit

Decentralized Cooperative Metaheuristic for the Dynamic Berth Allocation Problem

The increasing demand of maritime transport and the great competition among port terminals force their managers to reduce costs by exploiting its resources accurately. In this environment, the Berth Allocation Problem, which aims to allocate and schedule incoming vessels along the quay, plays a relevant role in improving the overall terminal productivity. In order to address this problem, we propose Decentralized Cooperative Metaheuristic (DCM), which is a population-based approach that exploits the concepts of communication and grouping. In DCM, the individuals are organized into groups, where each individual shares information with its group partners. This grouping strategy allows to diversify as well as intensify the search in some regions by means of information shared among the individuals of each group. Moreover, the constrained relation for sharing information among individuals through the proposed grouping strategy allows to reduce computational resources in comparison to the `all to all' communication strategy. The computational experiments for this problem reveal that DCM reports high-quality solutions and identifies promising regions within the search space in short computational times

Psychometric properties of a revised Spanish 20-item Toronto Alexithymia Scale adaptation in multiple sclerosis patients

There have been a small number of investigations of alexithymia in multiple sclerosis (MS) using the 20-item Toronto Alexithymia Scale (TAS-20). However, the TAS-20 factor structure has not yet been evaluated in a MS patient sample, and earlier Spanish translations of this instrument require some improvement. We aimed to evaluate the factorial validity and reliability of an improved Spanish translation of the TAS-20 (the TAS-20-S). The TAS-20-S was completed by 221 MS patients. Confirmatory factor analysis was used to compare the fit of six different factor models. Internal consistency and retest reliability coefficients were also computed. The correlated three-factor model and the higher-order factor model made up of Difficulty Identifying Feelings, Difficulty Describing Feelings, and Externally Oriented Thinking achieved the best fit. Alpha coefficients ranged between .87 and .67; mean inter-item correlations ranged between .48 and .20; and retest correlations after 6 months ranged between .61 and .52. A high degree of alexithymia was present in 18.1% of the sample. Reliability and the traditional three-factor structure were demonstrated for the TAS-20-S, which can now be recommended for assessing an aspect of emotional processing in MS patients.En la esclerosis múltiple (EM) son escasas las investigaciones centradas en evaluar la alexitimia con la Escala de Alexitimia de Toronto (TAS-20). A pesar de ello, no se ha evaluado aún su estructura factorial en dicha población y, además, las anteriores traducciones al español necesitan modificaciones. Los objetivos del presente estudio fueron evaluar la validez factorial y la fiabilidad de una traducción mejorada en español de la TAS-20 (la TAS-20-S), la cual fue administrada en una muestra de 221 pacientes con EM. Se realizaron análisis factoriales confirmatorios para comparar el ajuste de seis modelos factoriales. También se calcularon coeficientes de consistencia interna y de fiabilidad test-retest. Los modelos trifactorial correlacionado y el de orden superior conformados por Dificultad en Identificar Sentimientos, Dificultad en Describir Sentimientos y Pensamiento Externamente Orientado lograron el mejor ajuste. Los coeficientes alfa oscilaron entre 0,87 y 0,67; las correlaciones medias inter-ítem entre 0,48 y 0,20; y las correlaciones test-retest tras 6 meses oscilaron entre 0,61 y 0,52. El 18,10% de la muestra presentó niveles elevados de alexitimia. La TAS-20-S presentó una adecuada fiabilidad así como la tradicional estructura trifactorial, por lo que su uso es ahora recomendable para evaluar un aspecto del procesamiento emocional en EM.Ministerio de Educación, Cultura y Deporte de España Programa FPU (Formación del Profesorado Universitario

Novel population pharmacokinetic model for Linezolid in critically Ill patients and evaluation of the adequacy of the current dosing recommendation

Antimicrobial treatment in critically ill patients remains challenging. The aim of this study was to develop a population pharmacokinetic model for linezolid in critically ill patients and to evaluate the adequacy of current dosing recommendation (600 mg/12 h). Forty inpatients were included, 23 of whom were subjected to continuous renal replacement therapies (CRRT). Blood and effluent samples were drawn after linezolid administration at defined time points, and linezolid levels were measured. A population pharmacokinetic model was developed, using NONMEM 7.3. The percentage of patients that achieved the pharmacokinetic/pharmacodynamic (PK/PD) targets was calculated (AUC24/MIC > 80 and 100% T>MIC). A two-compartment model best described the pharmacokinetics of linezolid. Elimination was conditioned by the creatinine clearance and by the extra-corporeal clearance if the patient was subjected to CRRT. For most patients, the standard dose of linezolid did not cover infections caused by pathogens with MIC ≥ 2 mg/L. Continuous infusion may be an alternative, especially when renal function is preserved

Mapping pediatric palliative care development in the WHO-European Region: children living in low-middle income countries are less likely to access it

Context: Approximately 170,000 children in need of palliative care die every year in Europe without access to it. This field remains an evolving specialty with unexplored development. Objectives: To conduct the first regional assessment of pediatric palliative care (PPC) development and provision using data from the European Association for Palliative Care atlas of palliative care 2019. Methods: Two surveys were conducted. The first one included a single question regarding PPC service provision and was addressed by European Association for Palliative Care atlas informants. The second one included 10 specific indicators derived from an open-ended interview and rating process; a specific network of informants was enabled and used as respondents. Data were analyzed and presented in the map of the figure. Results: Data on PPC service provision were gathered from 51 of 54 (94%) European countries. Additional data were collected in 34 of 54 (62%) countries. A total of 680 PPC services were identified including 133 hospices, 385 home care services, and 162 hospital services. Nineteen countries had specific standards and norms for the provision of PPC. Twenty-two countries had a national association, and 14 countries offered education for either pediatric doctors or nurses. In seven countries, specific neonatal palliative care referral services were identified. Conclusion: PPC provision is flourishing across the region; however, development is less accentuated in low-to-middle-income countries. Efforts need to be devoted to the conceptualization and definition of the models of care used to respond to the unmet need of PPC in Europe. The question whether specialized services are required or not should be further explored. Strategies to regulate and cover patients in need should be adapted to each national health system

A stochastic neuronal model predicts random search behaviors at multiple spatial scales in C. elegans

Random search is a behavioral strategy used by organisms from bacteria to humans to locate food that is randomly distributed and undetectable at a distance. We investigated this behavior in the nematode Caenorhabditis elegans, an organism with a small, well-described nervous system. Here we formulate a mathematical model of random search abstracted from the C. elegans connectome and fit to a large-scale kinematic analysis of C. elegans behavior at submicron resolution. The model predicts behavioral effects of neuronal ablations and genetic perturbations, as well as unexpected aspects of wild type behavior. The predictive success of the model indicates that random search in C. elegans can be understood in terms of a neuronal flip-flop circuit involving reciprocal inhibition between two populations of stochastic neurons. Our findings establish a unified theoretical framework for understanding C. elegans locomotion and a testable neuronal model of random search that can be applied to other organisms

Trends analysis of specialized palliative care services in 51 countries of the WHO European region in the last 14 years

Background: Service provision is a key domain to assess national-level palliative care development. Three editions of the European Association for Palliative Care (EAPC) Atlas of Palliative Care monitored the changes in service provision across Europe since 2005. Aim: To study European trends of specialized service provision at home care teams, hospital support teams, and inpatient palliative care services between 2005 and 2019. Design: Secondary analysis was conducted drawing from databases on the number of specialized services in 2005, 2012, and 2019. Ratios of services per 100,000 inhabitants and increase rates on number of services for three periods were calculated. Analysis of variance (ANOVA) analyses were conducted to determine significant changes and chi-square to identify countries accounting for the variance. Income-level and sub-regional ANOVA analysis were undertaken. Setting: 51 countries. Results: Forty-two countries (82%) increased the number of specialized services between 2005 and 2019 with changes for home care teams (104% increase-rate), inpatient services (82%), and hospital support teams (48%). High-income countries showed significant increase in all types of services (p < 0.001), while low-to-middle-income countries showed significant increase only for inpatient services. Central–Eastern European countries showed significant improvement in home care teams and inpatient services, while Western countries showed significant improvement in hospital support and home care teams. Home care was the most prominent service in Western Europe. Conclusion: Specialized service provision increased throughout Europe, yet ratios per 100,000 inhabitants fell below the EAPC recommendations. Western Europe ratios’ achieved half of the suggested services, while Central–Eastern countries achieved only a fourth. High-income countries and Western European countries account for the major increase. Central–Eastern Europe and low-to-middle-income countries reported little increase on specialized service provision

Use of "ChemSensor" as an early discrimination tool of Iberian pig semen according to their freezability

Para favorecer el uso de dosis de inseminación de semen de porcino congelado-descongelado a nivel comercial, sería interesante conocer de antemano si el semen de verraco congelará bien o mal. El objetivo de este estudio fue evaluar el 'ChemSensor' (cromatógrafo de gases-masas unido a un software de análisis quimiométrico) como herramienta precoz de discriminación entre eyaculados según su congelabilidad. Para ello se utilizaron 33 eyaculados de verracos de raza Ibérica de los cuales se cogió una alícuota de 1 ml de semen y se analizó con el 'ChemSensor', el resto del eyaculado fue congelado-descongelado usando un protocolo estandarizado, para determinar su congelabilidad (buenos y malos congeladores) en función del porcentaje de espermatozoides con la membrana plasmática intacta y el porcentaje de espermatozoides móviles totales post-descongelación. Para el análisis con el 'ChemSensor', las muestras se volatilizaron e ionizaron descomponiéndolas en diferentes iones con un tamaño determinado, que se usaron como variables de discriminación, para separar los eyaculados en función de su congelabilidad. El 'ChemSensor' fue capaz de discriminar todos los eyaculados de los buenos congeladores; y dentro del grupo de los malos congeladores solamente una muestra fue clasificada erróneamente. Debido al reducido número de muestras, la distancia obtenida entre grupos (2,62), aunque no muy elevada, podría considerarse como significativa, aunque sería necesario un mayor número de muestras para poder crear un modelo matemático más robusto. En conclusión, el 'ChemSensor' es una posible herramienta adecuada para la discriminación precoz de eyaculados de cerdo Ibérico en función de su congelabilidad