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This study analyzes the effect of spatial competition on public schools' efficiency in Chile, an extreme case of market-oriented reforms in the educational sector. To address this issue, we use a measure of competition that captures three major characteristics of market competition in a spatial context: the number of competitors, based on distance buffers; the size of competitors, measured by the enrollment of voucher schools; and the geographical distance among public schools and their competitors. To control for the potential endogeneity of our measure of spatial competition on public schools' efficiency, we use an instrumental variable based on the discontinuites generated by admissions municipality boundaries . We do not find evidence that public schools' efficiency increases or decreases as the result of the increment of voucher schools located near to public schools, an increase in the enrollment of existing voucher schools, or both factors simultaneously. This result is robust to: (1) the limit of education market or other measures of spatial competition; (2) the methodology used to compute the efficiency measures; and (3) whether we explain efficiency or educational performance.

Con el objetivo de estudiar la composición fenológica y química de 6 variedades de caña de azúcar para ser utilizadas en la alimentación animal se realizó un experimento en áreas del banco de semilla básica ubicado en el batey Espartaco en la provincia de Cienfuegos sobre un suelo Pardo con carbonato (cambisol eutrico), Se utilizó un diseño experimental de bloques al azar, con un modelo de clasificación simple. Cada variedad ocupó un área de 64 m2 (4 surcos de 10 m), en la cepa caña planta, con edades entre 12 y 14 meses de edad, se tomaron tres muestras al azar (réplicas) de cada variedad. Se calcularon los valores de las variables morfológicas peso fresco del tallo, cogollo y hojas secas por la metodología de Molina y Tuero. Para el estudio de la composición química se estudiaron las variables digestibilidad de la materia seca, contenido de fibra ácida detergente, lignina, proteína bruta. Se realizaron análisis de varianza y comparación de medias por la prueba de comparación múltiple de Newman Keuls con las variables fenológicas y químicas. Se confeccionó análisis de conglomerados con las variables, digestibilidad, fibra ácida detergente y lignina. Como resultado se encontraron diferencias significativas en la composición fenológica y química en las variedades estudiadas, el análisis de conglomerados definió 3 grupos lo que permitió recomendar los cultivares C05-307, C05-568, C08-386, para la alimentación animal.

(1) Background: Liver metastases (LM) are the leading cause of death in colorectal cancer (CRC) patients. Despite advancements, relapse rates remain high and current prognostic nomograms lack accuracy. Our objective is to develop an interpretable neoadjuvant algorithm based on mathematical models to accurately predict individual risk, ensuring mathematical transparency and auditability. (2) Methods: We retrospectively evaluated 86 CRC patients with LM treated with neoadjuvant systemic therapy followed by complete surgical resection. A comprehensive analysis of 155 individual patient variables was performed. Logistic regression (LR) was utilized to develop the predictive model for relapse risk through significance testing and ANOVA analysis. Due to data limitations, gradient boosting machine (GBM) and synthetic data were also used. (3) Results: The model was based on data from 74 patients (12 were excluded). After a median follow-up of 58 months, 5-year relapse-free survival (RFS) rate was 33% and 5-year overall survival (OS) rate was 60.7%. Fifteen key variables were used to train the GBM model, which showed promising accuracy (0.82), sensitivity (0.59), and specificity (0.96) in predicting relapse. Similar results were obtained when external validation was performed as well. (4) Conclusions: This model offers an alternative for predicting individual relapse risk, aiding in personalized adjuvant therapy and follow-up strategies.

Resumen: Introducción: La aplicación de la inteligencia artificial y en particular de algoritmos de aprendizaje automático o «machine learning» (ML) constituye un desafío y al mismo tiempo una gran oportunidad en diversas disciplinas científicas, técnicas y clínicas. Las aplicaciones específicas en el estudio de la esclerosis múltiple (EM) no han sido una excepción mostrando un creciente interés en los últimos años. Objetivo: Realizar una revisión sistemática de la aplicación de algoritmos de ML en la EM. Material y métodos: Empleando el motor de búsqueda de libre acceso PubMed que accede a la base de datos MEDLINE, se seleccionaron aquellos estudios que incluyeran simultáneamente los dos siguientes conceptos de búsqueda: «machine learning» y «multiple sclerosis». Se rechazaron aquellos estudios que fueran revisiones, estuvieran en otro idioma que no fuera el castellano o el inglés, y aquellos trabajos que tuvieran un carácter técnico y no fueran aplicados para la EM. Se seleccionaron como válidos 76 artículos y fueron rechazados 38. Conclusiones: Tras la revisión de los estudios seleccionados, se pudo observar que la aplicación del ML en la EM se concentró en cuatro categorías: 1) clasificación de subtipos de pacientes dentro de la enfermedad; 2) diagnóstico del paciente frente a controles sanos u otras enfermedades; 3) predicción de la evolución o de la respuesta a intervenciones terapéuticas y por último 4) otros enfoques. Los resultados hallados hasta la fecha muestran que los diferentes algoritmos de ML pueden ser un gran apoyo para el profesional sanitario tanto en la clínica como en la investigación de la EM. Abstract: Introduction: The applications of artificial intelligence, and in particular automatic learning or “machine learning” (ML), constitute both a challenge and a great opportunity in numerous scientific, technical, and clinical disciplines. Specific applications in the study of multiple sclerosis (MS) have been no exception, and constitute an area of increasing interest in recent years. Objective: We present a systematic review of the application of ML algorithms in MS. Materials and methods: We used the PubMed search engine, which allows free access to the MEDLINE medical database, to identify studies including the keywords “machine learning” and “multiple sclerosis.” We excluded review articles, studies written in languages other than English or Spanish, and studies that were mainly technical and did not specifically apply to MS. The final selection included 76 articles, and 38 were rejected. Conclusions: After the review process, we established 4 main applications of ML in MS: 1) classifying MS subtypes; 2) distinguishing patients with MS from healthy controls and individuals with other diseases; 3) predicting progression and response to therapeutic interventions; and 4) other applications. Results found to date have shown that ML algorithms may offer great support for health professionals both in clinical settings and in research into MS.

Abstract There is an increasing demand to enhance infrastructure asset management within the drinking water sector. A key factor for achieving this is improving the accuracy of pipe failure prediction models. Machine learning-based models have emerged as a powerful tool in enhancing the predictive capabilities of water distribution network models. Extensive research has been conducted to explore the role of explanatory variables in optimizing model outputs. However, the underlying mechanisms of incorporating explanatory variable data into the models still need to be better understood. This review aims to expand our understanding of explanatory variables and their relationship with existing models through a comprehensive investigation of the explanatory variables employed in models over the past 15 years. The review underscores the importance of obtaining a substantial and reliable dataset directly from Water Utilities databases. Only with a sizeable dataset containing high-quality data can we better understand how all the variables interact, a crucial prerequisite before assessing the performance of pipe failure rate prediction models.

En este artículo se presentan los resultados de una investigación que analizó los desafíos de la democracia en la sociedad colombiana contemporánea a través de las prácticas de participación ciudadana en línea. Se llevó a cabo un estudio descriptivo transversal, con uso de técnicas de recolección cuantitativas y cualitativas orientadas a analizar las prácticas de participación ciudadana de jóvenes universitarios en la ciudad de Cali-Colombia. De una población de 1.233, se tomó una muestra representativa de 740 estudiantes a quienes se aplicó un cuestionario electrónico y, posteriormente, mediante un muestreo intencional, se desarrollaron grupos de discusión con 42 participantes. Se propusieron tres ejes a partir de los principios generales de la democracia digital (E-democracy): Consulta, control político y participación transformadora. Como resultado se encontró que las prácticas de ciudadanía en línea no se complementan con las prácticas ciudadanas fuera de línea, situación que se describe como un desafío para la democracia digital que se ve masificada en la información y altamente restringida en la acción. Por tanto, se concluye que la democracia digital no ha significado un mayor compromiso con la transformación socio-política de la sociedad por parte de los jóvenes que ejercen mecanismo de participación ciudadana en línea.

The forms of citizen participation have been reconfigured in recent years. The presence of social networks and digital media in general have favored multiple modes of access to information, expression of ideas and social participation. A necessary reflection to think about a sustainable future requires an assessment of communicative practices in digital media and the challenges in citizen education that globalization entails. This research focused on the analysis of citizen participation practices of university students in digital media and its implications for global citizenship. A mixed investigation with a quantitative-qualitative sequence was proposed. In the first phase, a cross-sectional descriptive study was developed with 740 students from a Colombian university, to whom an electronic questionnaire was applied. In the second qualitative phase, discussion groups were held with 42 students, with the purpose of discussing the findings of the questionnaire from the perspective of the participants. It was found that the practices conducted by the students focus mostly on basic and intermediate levels of citizenship represented in the consultation of online information and expression of the ideological positions in social networks, with high limitations towards higher levels of citizenship referred to concrete actions to impact reality. It is evident that this difficulty in contributing to social changes in the world is due to the lack of education for critical global citizenship. Therefore, critical literacy for the use of digital media is proposed as a citizen educational strategy, considering that it contributes to the construction of a more hopeful vision of the future.

BackgroundUp to one-fifth of patients continue to have poor quality of life after transcatheter aortic valve implantation (TAVI), with an additional similar proportion not surviving 1 year after the procedure. We aimed to assess the value of a new method based on an integrated analysis of left ventricular outflow tract flow velocity and aortic pressure to predict objective functional improvement and prognosis after TAVI.MethodsIn a cohort of consecutive patients undergoing TAVI, flow velocity–pressure integrated analysis was obtained from simultaneous pressure recordings in the ascending aorta and flow velocity recordings in the left ventricular outflow tract by echocardiography. Objective functional improvement 6 months after TAVI was assessed through changes in a 6-min walk test and NT-proBNP levels. A clinical follow-up was conducted at 2 years.ResultsOf the 102 patients studied, 82 (80.4%) showed objective functional improvement. The 2-year mortality of these patients was significantly lower (9% vs. 44%, p = 0.001). In multivariate analysis, parameter “(Pressure at Vmax − Pressure at Vo)/Vmax” was found to be an independent predictor for objective improvement. The C-statistic was 0.70 in the overall population and 0.78 in the low-gradient subgroup. All echocardiographic parameters and the valvuloarterial impedance showed a C-statistic of

Resumen: Introducción: Comprender las alteraciones en la anatomía y función del cerebro en los procesos cognitivos para las enfermedades neurodegenerativas es aún un desafío para la neurociencia actual. Desde la neurociencia experimental algunos test computarizados han sido desarrollados para mejorar nuestro conocimiento de las redes neurales involucradas en la cognición. El Attention Network Test (ANT) permite medir la activad de las 3 redes atencionales (alerta, orientación y función ejecutiva). Objetivos: El principal objetivo de esta revisión fue describir todas las alteraciones anatómicas y funcionales encontradas en diversas enfermedades neurológicas usando el ANT. Material y métodos: Un protocolo de revisión fue aplicado seleccionando estudios desde 2010 en la base de datos PubMed, que involucraban al ATN en diferentes enfermedades neurológicas. Se obtuvieron 32 artículos para esclerosis múltiple, epilepsia o Parkinson entre otras enfermedades. Conclusiones: Se confirman algunas de las estructuras anatómicas propuestas para el modelo de 3 grandes redes atencionales. Las estructuras más relevantes para la red de alerta son la corteza prefrontal, las regiones parietales, el tálamo y el cerebelo. El tálamo es también relevante para la red de orientación, junto a regiones parietales posteriores. Respecto a la red ejecutiva no depende exclusivamente de la corteza prefrontal y corteza cingulada anterior, sino también de estructuras subcorticales como los ganglios basales y el cerebelo y sus proyecciones hacia toda la corteza. Abstract: Introduction: Understanding alterations to brain anatomy and cognitive function associated with neurodegenerative diseases remains a challenge for neuroscience today. In experimental neuroscience, several computerised tests have been developed to contribute to our understanding of neural networks involved in cognition. The Attention Network Test (ANT) enables us to measure the activity of 3 attentional networks (alertness, orienting, and executive function). Objectives: The main aim of this review is to describe all the anatomical and functional alterations found in diverse neurological diseases using the ANT. Material and methods: We collected studies published since 2010 in the PubMed database that employed the ANT in different neurological diseases. Thirty-two articles were obtained, addressing multiple sclerosis, epilepsy, and Parkinson's disease, among other disorders. Conclusions: Some of the anatomical structures proposed in the 3 attentional networks model were confirmed. The most relevant structures in the alertness network are the prefrontal cortex, parietal region, thalamus, and cerebellum. The thalamus is also relevant in the orienting network, together with posterior parietal regions. The executive network does not depend exclusively on the prefrontal cortex and anterior cingulate cortex, but also involves such subcortical structures as the basal ganglia and cerebellum and their projections towards the entire cortex.

Introduction: Understanding alterations to brain anatomy and cognitive function associated with neurodegenerative diseases remains a challenge for neuroscience today. In experimental neuroscience, several computerised tests have been developed to contribute to our understanding of neural networks involved in cognition. The Attention Network Test (ANT) enables us to measure the activity of 3 attentional networks (alertness, orienting, and executive function). Objectives: The main aim of this review is to describe all the anatomical and functional alterations found in diverse neurological diseases using the ANT. Material and methods: We collected studies published since 2010 in the PubMed database that employed the ANT in different neurological diseases. Thirty-two articles were obtained, addressing multiple sclerosis, epilepsy, and Parkinson’s disease, among other disorders. Conclusions: Some of the anatomical structures proposed in the 3 attentional networks model were confirmed. The most relevant structures in the alertness network are the prefrontal cortex, parietal region, thalamus, and cerebellum. The thalamus is also relevant in the orienting network, together with posterior parietal regions. The executive network does not depend exclusively on the prefrontal cortex and anterior cingulate cortex, but also involves such subcortical structures as the basal ganglia and cerebellum and their projections towards the entire cortex. Resumen: Introducción: Comprender las alteraciones en la anatomía y función del cerebro en los procesos cognitivos para las enfermedades neurodegenerativas es aún un desafío para la neurociencia actual. Desde la neurociencia experimental, algunos tests computarizados han sido desarrollados para mejorar nuestro conocimiento de las redes neurales involucradas en la cognición. El Attention Network Test (ANT) permite medir la activad de las tres redes atencionales (alerta, orientación y función ejecutiva). Objetivos: El principal objetivo de esta revisión fue describir todas las alteraciones anatómicas y funcionales encontradas en diversas enfermedades neurológicas usando el ANT. Material y métodos: Un protocolo de revisión fue aplicado seleccionando estudios desde 2010 en la base de datos PubMed que involucraban al Attention Network Test en diferentes enfermedades neurológicas. Se obtuvieron treinta y dos artículos para esclerosis múltiple, epilepsia o Parkinson entre otras patologías. Conclusiones: Se confirman algunas de las estructuras anatómicas propuestas para el modelo de tres grandes redes atencionales. Las estructuras más relevantes para la red de alerta son la corteza prefrontal, regiones parietales, tálamo y el cerebelo. El tálamo es también relevante para la red de orientación, junto a regiones parietales posteriores. Respecto a la red ejecutiva, no depende exclusivamente de la corteza prefrontal y corteza cingulada anterior, sino también de estructuras subcorticales como los ganglios basales y el cerebelo y sus proyecciones hacia toda la corteza.

Despite the huge availability of software to estimate cross-sectional spatial models, there are only few functions to estimate models dealing with spatial limited dependent variable. This paper fills this gap introducing the new R package spldv. The package is based on generalized methods of moment (GMM) estimators and includes a series of one- and two-step estimators based on different choices of the weighting matrix for the moments conditions in the first step, and different estimators for the variance-covariance matrix of the estimated coefficients. An important feature of spldv is that users can estimate the spatial Durbin model and compute the direct, indirect, and total effects in a friendly and flexible way.

Background and objectivesIntermittent theta-burst stimulation (iTBS) is a patterned form of excitatory transcranial magnetic stimulation that has yielded encouraging results as an adjunctive therapeutic option to alleviate the emergence of clinical deficits in Parkinson’s disease (PD) patients. Although it has been demonstrated that iTBS influences dopamine-dependent corticostriatal plasticity, little research has examined the neurobiological mechanisms underlying iTBS-induced clinical enhancement. Here, our primary goal is to verify whether iTBS bilaterally delivered over the primary motor cortex (M1) is effective as an add-on treatment at reducing scores for both motor functional impairment and nonmotor symptoms in PD. We hypothesize that these clinical improvements following bilateral M1-iTBS could be driven by endogenous dopamine release, which may rebalance cortical excitability and restore compensatory striatal volume changes, resulting in increased striato-cortico-cerebellar functional connectivity and positively impacting neuroglia and neuroplasticity.MethodsA total of 24 PD patients will be assessed in a randomized, double-blind, sham-controlled crossover study involving the application of iTBS over the bilateral M1 (M1 iTBS). Patients on medication will be randomly assigned to receive real iTBS or control (sham) stimulation and will undergo 5 consecutive sessions (5 days) of iTBS over the bilateral M1 separated by a 3-month washout period. Motor evaluation will be performed at different follow-up visits along with a comprehensive neurocognitive assessment; evaluation of M1 excitability; combined structural magnetic resonance imaging (MRI), resting-state electroencephalography and functional MRI; and serum biomarker quantification of neuroaxonal damage, astrocytic reactivity, and neural plasticity prior to and after iTBS.DiscussionThe findings of this study will help to clarify the efficiency of M1 iTBS for the treatment of PD and further provide specific neurobiological insights into improvements in motor and nonmotor symptoms in these patients. This novel project aims to yield more detailed structural and functional brain evaluations than previous studies while using a noninvasive approach, with the potential to identify prognostic neuroprotective biomarkers and elucidate the structural and functional mechanisms of M1 iTBS-induced plasticity in the cortico-basal ganglia circuitry. Our approach may significantly optimize neuromodulation paradigms to ensure state-of-the-art and scalable rehabilitative treatment to alleviate motor and nonmotor symptoms of PD.

Motivation: For a number of neurological diseases, such as Alzheimer’s disease, amyotrophic lateral sclerosis, and many others, certain genes are known to be involved in the disease mechanism. A common question is whether a structural variant in any such gene may be related to drug response in clinical trials and how this relationship can contribute to the lifecycle of drug development.Results: To this end, we introduce VariantSurvival, a tool that identifies changes in survival relative to structural variants within target genes. VariantSurvival matches annotated structural variants with genes that are clinically relevant to neurological diseases. A Cox regression model determines the change in survival between the placebo and clinical trial groups with respect to the number of structural variants in the drug target genes. We demonstrate the functionality of our approach with the exemplary case of the SETX gene. VariantSurvival has a user-friendly and lightweight graphical user interface built on the shiny web application package.

Abstract Recent studies have suggested that nonphase-locked activity can reveal cognitive mechanisms that cannot be observed in phase-locked activity. In fact, we describe a concomitant decrease in nonphase-locked alpha activity (desynchronization) when stimuli were processed (alpha phase-locked modulation). This desynchronization may represent a reduction in “background activity” in the visual cortex that facilitates stimulus processing. Alternatively, nonphase-locked gamma activity has been hypothesized to be an index of shifts in attentional focus. In this study, our main aim was to confirm these potential roles for nonphase-locked alpha and gamma activities with a lateralized Go/NoGo paradigm. The results showed that nonphase-locked alpha modulation is bilaterally represented in the scalp compared to the contralateral distribution of the phase-locked response. This finding suggests that the decrease in background activity is not limited to neural areas directly involved in the visual processing of stimuli. Additionally, gamma activity showed a higher desynchronization of nonphase-locked activity in the ipsilateral hemisphere, where the phase-locked activity reached the minimum amplitude. This finding suggests that the possible functions of nonphase-locked gamma activity extend beyond shifts in attentional focus and could represent an attentional filter reducing the gamma representation in the visual area irrelevant to the task.