Visual Rationalizations in Deep Reinforcement Learning for Atari Games

Due to the capability of deep learning to perform well in high dimensional problems, deep reinforcement learning agents perform well in challenging tasks such as Atari 2600 games. However, clearly explaining why a certain action is taken by the agent can be as important as the decision itself. Deep reinforcement learning models, as other deep learning models, tend to be opaque in their decision-making process. In this work, we propose to make deep reinforcement learning more transparent by visualizing the evidence on which the agent bases its decision. In this work, we emphasize the importance of producing a justification for an observed action, which could be applied to a black-box decision agent.Comment: presented as oral talk at BNAIC 201

Dry and starchy orange-fleshed sweetpotato farmer varieties: Implications for fighting vitamin A defiency in East and Central Africa.

Sweetpotato is a major staple and co-staple root crop for millions of the rural people in Africa. Recently, it has been demonstrated to be of human health importance by combating vitamin A deficiency. This paper is a summary review of recent findings on the orange-fleshed sweetpotato (OFSP) farmer varieties (FV) from East Africa (EA) and their potential contribution to combat vitamin A deficiency (VAD) in Africa. Between 2000 and 2006, scientists from East and Central Africa collected several OFSP varieties from farmers' fields together with the white- and creamfleshed sweetpotato (WFSP) farmer varieties. Subsequent characterization studies using selected EA and exotic germplasm revealed critical findings for the future use of OFSP FV in Africa. Overall, molecular characterization showed that EA germplasm is distinct from non-African germplasm. It also showed that OFSP FV and WFSP FV from EA are very closely related. The two findings address suspicions that OFSP FV are of exotic origin. The OFSP FV differed from exotic OFSP on root dry matter (DM), starch and sucrose properties. Whereas the exotic OFSP are characteristically 'sweet and moist' (DM ≈ 25.0%, starch ≈50.0% and sucrose ≈ 10.3%), OFSP FV had characteristically high DM (≈33.0%), high starch (≈ 65.0%) and similar to the WFSP FV. It is these qualities that make sweetpotato a staple crop in Africa. However, root â-carotene content (BC) of some OFSP FV ['Ejumula', 240pmm; 'Carrot C', 259 ppm; 'Mayai', 264 ppm; and 'Zambezi', 233 ppm] nearly equaled that of 'Resisto' (271ppm), one of the popular OFSP cultivars in USA. These were shown to meet ≥400% of recommended daily allowance (RDA) with 250 g serving to a 5-8 year old child Other light orange-fleshed FV like 'ARA244 Shinyanga', 'K-118', 'K-134', 'K-46', 'PAL161', 'Sowola6', 'SRT52', and 'Sudan' had lower root BC than 'Resisto' and were shown to meet between 50-90% RDA of the child. In conclusion, OFSP FV from EA might show similar adaptation to sub- Sahara African environments as their sister WFSP and have a big potential to alleviate VAD. Also, breeding for acceptable high DM and high starch OFSP varieties for African consumers seems possibl

Diseño de un plan de gestión de mantenimiento para mejorar la disponibilidad de los equipos de bombeo en una planta minera

El objetivo de la tesis fue diseñar un plan de gestión de mantenimiento para mejorar la disponibilidad de los equipos de bombeo en una planta minera, para ello se establecieron objetivos específicos que fueron; realizar un diagnóstico actual de los equipos del sistema de bombeo, elaborar el plan de gestión de mantenimiento, realizar el análisis de las mejoras en la disponibilidad de los equipos y realizar la viabilidad económica del plan. La investigación fue aplicada, explicativa, cuantitativa y no experimental. El problema con mayor impacto en la planta es la baja disponibilidad de los equipos debido a un inadecuado plan de mantenimiento, la disponibilidad actual es 73% en promedio. El plan de gestión de mantenimiento de los equipos del sistema de bombeo consiste en la elaboración de las políticas de mantenimiento, formato para reporte de fallas, check list, el procedimiento estándar de trabajo para el mantenimiento de bombas y la ficha de control de parámetros de operación y funcionamiento. La disponibilidad de los equipos de bombeo con el plan de mantenimiento se incrementó en 13%. Este plan tiene un VAN de 267 176 dólares, TIR es 100.53% y la relación B/C es 0.71. por lo tanto, el proyecto es viable económicamente y representa altos ahorros para la empresa minera

Análisis de fallas y confiabilidad de sellos mecánicos en bombas de lodos: una revisión sistemática

RESUMEN Para la optimización del sistema de bombeo es necesario analizar las fallas en los sellos mecánicos; es ahí donde se presenta la mayor cantidad de problemas en las bombas de lodos. Las fallas se presentan constantemente en los sellos mecánicos y afectan a los equipos empleados en el sistema de bombeo, generando reducción de producción y pérdida de tiempo, lo cual se traduce en pérdidas económicas, pero con un adecuado análisis de fallas se evitarían dichas pérdidas generando mayor rentabilidad. El objetivo fue analizar teóricamente la optimización del sistema de bombeo mediante el análisis de fallas en sellos mecánicos en bombas de lodos, en los últimos 5 años: se usó las bases de datos Redalyc y Ebsco. Los términos de inclusión fueron optimización del sistema de bombeo, reducción de fallas y rendimiento de sellos mecánicos. Se sintetizaron 21 estudios centrados en optimización de sistema de bombeo en plantas mineras. En los estudios teóricos se especificó que las fallas están en la instalación, en el diseño de los sellos y/o en la contaminación del líquido. Los documentos encontrados mayormente pertenecen al 2017. Los estudios encontrados fuera del país se enfocaron en el diseño de sellos mecánicos descritas por las empresas fabricadoras. PALABRAS CLAVES: .Optimización, fallas, sellos mecánicos, sistema de bombeo

Towards a sustainable and equitable blue economy

The global rush to develop the \u2018blue economy\u2019 risks harming both the marine environment and human wellbeing. Bold policies and actions are urgently needed. We identify five priorities to chart a course towards an environmentally sustainable and socially equitable blue economy

Default policies for global optimisation of noisy functions with severe noise

Global optimisation of unknown noisy functions is a daunting task that appears in domains ranging from games to control problems to meta-parameter optimisation for machine learning. We show how to incorporate heuristics to Stochastic Simultaneous Optimistic Optimization (STOSOO), a global optimisation algorithm that has very weak requirements from the function. In our case, heuristics come in the form of Covariance Matrix Adaptation Evolution Strategy (CMA-ES). The new algorithm, termed Guided STOSOO (STOSOO-G), combines the ability of CMA-ES for fast local convergence (due to the algorithm following the “natural” gradient) and the global optimisation abilities of STOSOO. We compare all three algorithms in the “harder” parts of the Comparing Continuous Optimisers on Black-Box Optimization Benchmarking benchmark suite, which provides a default set of functions for testing. We show that our approach keeps the best of both worlds, i.e. the almost optimal exploration/exploitation of STOSOO with the local optimisation strength of CMA-ES

The contribution of emission sources to the future air pollution disease burden in China

Air pollution exposure is a leading public health problem in China. Despite recent air quality improvements, fine particulate matter (PM2.5) exposure remains large, the associated disease burden is substantial, and population ageing is projected to increase the susceptibility to disease. Here, we used emulators of a regional chemical transport model to quantify the impacts of future emission scenarios on air pollution exposure in China. We estimated how key emission sectors contribute to these future health impacts from air pollution exposure. We found that PM2.5 exposure declines in all scenarios across China over 2020–2050, with reductions of 15% under current air quality legislation, 36% when exploiting the full potential of air pollutant emission reduction technologies, and 39% when that technical mitigation potential is combined with emission controls for climate mitigation. However, population ageing means that the PM2.5 disease burden under current legislation (CLE) increases by 17% in 2050 relative to 2020. In comparison to CLE in 2050, the application of the best air pollution technologies provides substantial health benefits, reducing the PM2.5 disease burden by 16%, avoiding 536 600 (95% uncertainty interval, 95UI: 497 800–573 300) premature deaths per year. These public health benefits are mainly due to reductions in industrial (43%) and residential (30%) emissions. Climate mitigation efforts combined with the best air pollution technologies leads to an additional 2% reduction in the PM2.5 disease burden, avoiding 57 000 (95UI: 52 800–61 100) premature deaths per year. Up to 90% of the 2020–2050 reductions in PM2.5 exposure are already achieved by 2030, assuming efficient implementation and enforcement of currently committed air quality policies in key sectors. Achieving reductions in PM2.5 exposure and the associated disease burden after 2030 will require further tightening of emission limits for regulated sectors, addressing other sources including agriculture and waste management, and international coordinated action to mitigate air pollution across Asia

Experience of 10 years in routine trans operative endoscopy and calibration in fundoplication due to gastroesophageal reflux disease

Background: Endoscopy and intraoperative calibration in fundoplication for gastroesophageal reflux disease (GERD), confirm an adequate technique avoiding postoperative failure. Intraoperative changes and morbidity in routine use are unknown.Methods: Retrospective study in a single center, data were taken primarily from electronic archive medical records. A total of 899 who underwent fundoplication surgery with endoscopy and/or routine intraoperative calibration due to GERD met the required criteria between 1 January 2010 and 31 December 2020. The primary objective was to identify the number of calibration and intraoperative endoscopy findings. Also, the morbidity associated with its routine use was analyzed.Results: Over a 10-year study period, the most frequent calibration in the Nissen Fundoplication was 60Fr in 472 cases (61.4 %). The most used calibration in Toupet Fundoplication was 60Fr in 26 cases (21.1%). Endoscopy was performed in 786 patients (71.38%), of which; 3 patients (0.3%) required changes, secondary to fundoplication rotation in 2 patients (0.2%) and redundant gastric fundus in 1 patient (0.1%).Conclusions: Routine intraoperative calibration and endoscopy achieved excellent results in 96.8% of fundoplication’s, ensuring adequate esophageal position and corroborating an adequate intraoperative technique; decreasing the rate of failures and immediate postoperative dysphagia

Symptoms associated with victimization in patients with schizophrenia and related disorders

Background: Patients with psychoses have an increased risk of becoming victims of violence. Previous studies have suggested that higher symptom levels are associated with a raised risk of becoming a victim of physical violence. There has been, however, no evidence on the type of symptoms that are linked with an increased risk of recent victimization. Methods: Data was taken from two studies on involuntarily admitted patients, one national study in England and an international one in six other European countries. In the week following admission, trained interviewers asked patients whether they had been victims of physical violence in the year prior to admission, and assessed symptoms on the Brief Psychiatric Rating Scale (BPRS). Only patients with a diagnosis of schizophrenia or related disorders (ICD-10 F20–29) were included in the analysis which was conducted separately for the two samples. Symptom levels assessed on the BPRS subscales were tested as predictors of victimization. Univariable and multivariable logistic regression models were fitted to estimate adjusted odds ratios. Results: Data from 383 patients in the English sample and 543 patients in the European sample was analysed. Rates of victimization were 37.8% and 28.0% respectively. In multivariable models, the BPRS manic subscale was significantly associated with victimization in both samples. Conclusions: Higher levels of manic symptoms indicate a raised risk of being a victim of violence in involuntary patients with schizophrenia and related disorders. This might be explained by higher activity levels, impaired judgement or poorer self-control in patients with manic symptoms. Such symptoms should be specifically considered in risk assessments

Age, sex, and setting in the etiology of stroke study (ASSESS): Study design and protocol

RATIONALE: Stroke etiology and risk factors vary by age, sex, setting (hospital or community-based) and by region. Identifying these differences would improve our understanding of stroke etiology, diagnosis, and treatment. AIM: The Age, Sex and Setting in the Etiology of Stroke Study (ASSESS) is a multicenter cohort study to assess differences in stroke etiology. METHODS AND DESIGN: Data from all centers will be categorized according to age, sex, setting, stroke subtypes. Centers with extensive hospital- or community-based data regarding stroke from Argentina, Australia, Canada, India, Iran, Italy, Ghana, Nigeria, Thailand, the United Kingdom and the United States have agreed to participate so far. STUDY OUTCOMES: The primary outcome includes differences in stroke etiology in study centers. The secondary outcomes include stroke incidence, risk factors, preventive strategies, and short- and long-term outcomes. CONCLUSION: ASSESS will enable comparisons of data from different regions to determine the age and sex distribution of the most common causes of stroke in each setting. This will help clinicians to tailor the assessment and treatment of stroke patients on the basis of their specific local characteristics. It will also empower stroke epidemiologists to design preventive measures by targeting the specific characteristics of each population