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Summary: This paper presents a new robust distributed approach for the energy management of rural multi‐microgrids communities in Chile. These rural communities are often geographically isolated and have a poor connection to the main electricity grid. Operating them as individual microgrids allows the community to connect to the grid or behave as a stand‐alone system (islanded). Connecting and coordinating the operation of the microgrids can improve the system's robustness to energy and demand uncertainty, as well as reducing the dependency on the main grid. However, this coordination can be challenging because the communication between the different microgrids can sometimes deteriorate, moreover, both load and local generation profiles are challenging to predict. For these reasons, in this paper, a new robust distributed hierarchical Energy Management System (EMS) for coordination of multiple microgrids (multi‐microgrids) is introduced, which uses robust distributed Model Predictive Control (MPC). Distributed optimisation permits improving reliability in the presence of poor or lack of communications between microgrids. To consider the uncertainty associated with renewable energy generation and load consumption, fuzzy prediction interval models are included in the MPC design. The proposed method is compared with robust centralised MPC and deterministic distributed MPC to assess its performance. Simulation results are presented using data representative of a rural community in coastal Chile applied to the robust MPC design. The outcomes of this work demonstrate that the proposed robust distributed EMS can improve the power supply, apply peak shaving, and can successfully operate when there is a loss of communication between microgrids. The use of decreasing fuzzy intervals allows an accurate prediction of both load and renewable energy generation, making the system robust to uncertainty in the available resources. Moreover, results show that in absence of communication, the power supply obtained under different scenarios with the distributed EMS is better than the equivalent centralised EMS. [ABSTRACT FROM AUTHOR]

This paper designs and implements a methodology to model the evolution of the COVID-19 pandemic, produced by the SARS-CoV-2 virus, in what was called the first wave in Chile, which lasted from March 2 to 31 October 2020. The models are based on sigmoidal growth curves and can be used to predict the number of daily infections and deaths in future days, making them a useful tool for sanitary authorities to manage an epidemic. The methodology is applied to the entire country and to each of its most affected regions. In addition, the dynamics of these models allow it to be nurtured with the new information that is being produced and forecast a tentative date on which there would be some control over the pandemic. Moreover, these models allow for predicting the total number of infected and deceased people at the time the pandemic is under control. However, the simplicity of these models, which consider only the accumulated data of those infected and deceased, does not contemplate an intervention analysis such as vaccinations, which, as is known, are being effective in controlling the pandemic. [ABSTRACT FROM AUTHOR]

Providing care for older people who have support needs is mainly a familial and female responsibility in Chile. Despite Chile's development level, the participation of females in the workforce lags behind (at around 50%), and 72% of female carers of an older relative are not in the labour force. This paper explores the reasons why in Latin America adult children remain out of the labour force while caring for an older parent or parent‐in‐law who has support needs. It draws on 30 in‐depth interviews of family carers from low‐ to high‐income households. The interviews were carried out in Chile in 2017, and were analysed using an inductive thematic analysis to identify core themes related to the subjects' reasons for remaining out of the labour force. Four factors hinder the combination of paid work and caring for a parent or parent‐in‐law with support needs: (a) externalised care was too expensive; (b) finding non‐precarious, flexible work was difficult; (c) their perception of femininity or womanhood conflicted with the idea of combining care and paid work; and (d) they experienced a lack of public and/or social support. [ABSTRACT FROM AUTHOR]

Energy consumption in the world is mainly dependent on fossil energy, and oil is one of the main energy sources. Accurate prediction of oil consumption can provide an important basis for national energy security, which can provide reference and early warning for the implementation of the environmental strategy developed by the government. According to the nonlinearity of the energy system, this paper uses the principle of the grey nonlinear prediction model NGBM(1,1) to improve the background value of the model, and by the simulated annealing algorithm, we put forward the optimized grey nonlinear model ONGBM(1,1). At the same time, the model is applied to the oil consumption of China, Chile, Mexico, and Japan. Based on the validity analysis of the existing data of the four countries, the model ONGBM(1,1) is basically superior to the other six grey forecast models. Finally, ONGBM(1,1) is used to predict the oil consumption of the four countries in the next five years, which can provide effective information for energy economic policy. [ABSTRACT FROM AUTHOR]

Our knowledge about the diversity of land planarians (Platyhelminthes: Geoplanidae) from the Andean‐Patagonian Forests is scarce compared with other forested biomes. These cold‐temperate forests are located in southern Chile and western Patagonia in Argentina, at the southern end of South America. Many species of land planarians from this region are known from descriptions based on a single or only a few specimens. Therefore, the finding of new material can reveal cryptic species, as well as anatomical or histological differences among specimens due to different maturation stages, physiological states, or intraspecific variation. In this paper, we focus on two geoplaninid species, Geoplana valdiviana and Amaga ruca, with the main goal of offering detailed re‐descriptions of both species (previously known from Chilean Patagonia) from new material recently found in Argentinean Patagonia. In this contribution, we added new information on histological and anatomical features of these species. After assessing taxonomically relevant anatomical characters together with DNA sequence data (mitochondrial COI gene and nuclear 18S rRNA gene), we took three taxonomic decisions: (a) G. valdiviana was removed from Geoplana and re‐allocated in the new genus Inakayalia; (b) Geoplana chanca and Geoplana tirua were also included in this new genus; and (c) A. ruca was split off from the genus Amaga and placed in the new monotypic genus Wallmapuplana. In addition, the known distribution of these planarian species was expanded to include the Argentinean portion of the Andean‐Patagonian Forests. [ABSTRACT FROM AUTHOR]

Summary: This paper presents a thermal power plant retrofitting approach focused on improvements in the operational flexibility of existing combined cycle power plants dedicated to providing thermal energy for medium and low‐temperature processes in copper mining facilities. The main motivation for this research was aimed at evaluating the operational flexibility of the electrical industry through sector coupling and its effect on solving the energy sector decarbonization issues. The research evaluates the advantages of hybridization systems for supporting the electrical and mining industries to better predict operations. The proposed approach is based on a dynamic simulation scheme that finds the optimal operating parameters of the combined heat and power (CHP) system, such as location, type, and arrangement of each component of the CHP system. The power plant dynamic simulation model was validated against data available in the literature; it was also characterized by real operational data of the San Isidro II power plant installed in Chile. Several alternatives for the cogeneration plant location, as well as the splitter system design, were investigated and then compared. A cogeneration plant design with two heating modules was selected based on the comparative study performed in this work and its CHP system was evaluated for a load reduction case study. The results were compared against a reference model. The proposed CHP system exhibited improved performance: a minimum of 15% of the exhaust gases are required to supply the thermal energy demand of the electrowinning process when a full load is considered. It was also found that an average decrease of 5% of the mechanical power at each steam turbine stage noted. Finally, the proposed CHP system's average thermodynamic efficiency is found to be 19% greater than the power plant average efficiency. Consequently, an average decrease of 32 500 tons of carbon dioxide emissions per year is predicted. [ABSTRACT FROM AUTHOR]

This paper describes PiMan, a CORBA-based system manager of the "Pi of the Sky" experiment, whose prototype consisting of two cameras on parallactic mount is running at Las Campanas Observatory in Chile. We discuss in detail all software components of the "Pi of the Sky" system, interactions between them, and the architecture of the PiMan system. PiMan extension and other system software that will control and monitor final system being under construction, consisting of two sites with 16 CCD cameras installed on three mounts per site, is also described in this paper. [ABSTRACT FROM AUTHOR]

Recently, a newcrossover technique for genetic algorithms has been proposed. The technique, called probabilistic adaptive crossover (PAX), includes the estimation of the probability distribution of the population, storing the information regarding the best and the worst solutions of the problem being solved in a probability vector. The use of the proposed technique to face Chilean wine classification based on chromatograms obtained froman HPLC is reported in this paper. PAX is used in the first stage as the feature selection method and then support vector machines (SVM) and linear discriminant analysis (LDA) are used as classifiers. The results are compared with those obtained using the uniform (discrete) crossover standard technique and a variant of PAX called mixed crossover. [ABSTRACT FROM AUTHOR]

Codner E, Soto N, Merino PM. Review of puberty, contraception, and pregnancy in adolescents with type 1 diabetes. Adolescence is a critical period for girls with type 1 diabetes mellitus (T1D). Reproductive issues, such as menstrual abnormalities, risk of an unplanned pregnancy, and contraception, should be addressed during this phase of life. This paper reviews several reproductive issues that are important in the care of adolescents, including pubertal development, menstrual abnormalities, ovulatory function, reproductive problems, the effects of hyperglycemia, contraception, and treatment of an unplanned pregnancy. A review of the literature was conducted. A MEDLINE search January 1966 to March 2011 was performed using the following MESH terms: puberty, menarche, ovary, polycystic ovary syndrome, menstruation, contraception, contraception-barrier, contraceptives-oral-hormonal, sex education, family planning services, and pregnancy in adolescence. This literature search was cross-referenced with an additional search on diabetes mellitus-type 1, diabetes complications, and pregnancy in diabetes. All published studies were searched regardless of the language of origin. Bibliographies were reviewed to extract additional relevant sources. [ABSTRACT FROM AUTHOR]

The paper deals with the major chemistry and stable isotopes (hydrogen, oxygen, carbon, sulfur, strontium) of waters and solutes from the Salar de Atacama basin (Rio Pedro, Honar Creek and Laguna Chaxa) and Andean Altiplano (Laguna Miñique and Laguna Miscanti). The water inflows of the Salar are chemically quite different, the Rio San Pedro being of Na-Cl type and the Honar Creek of Na-HCO3 type, in keeping with the sedimentary-evaporitic and volcanic nature of the catchment rocks respectively. The δ34S and δ18O values of sulfate and the 87Sr/86Sr ratio of strontium in the streams match those of drained rocks, whereas the δ13C values of dissolved carbonate are largely controlled by vegetation. The lagoons are evaporated meteoric water bodies, and the relative air humidity estimated from the slope of the isotopic evaporation line is in accordance with historical data on air humidity in the area. The Laguna Chaxa is Na-Cl rich, and its isotopic composition are consistent with a mixed sedimentary-volcanic provenance of sulfur and strontium solutes. The Laguna Miñique is Na-SO4 rich, and its sulfate δ34S is nearly identical to that of Laguna Chaxa. The δ13C(HCO3) values are quite different in the Laguna Chaxa and Laguna Miñique, with the former being notably enriched in 13C probably because of preferential uptake of 12C by the high biological productivity occurring in the lagoon. The limited set of new data is interpreted in the context of a much larger literature database. In particular, previous chemical data on inflows and brines in the Salar de Atacama were revisited, and compared with evaporation path models and mineral stability diagrams (boron, lithium and Mg-minerals) computed using updated software and thermodynamic databases. The modeling shows that the removal of boron and lithium from sulfate-rich brines possibly occurs, respectively, as ulexite and sulfate salts, and carnallite should be the final magnesium phase of the brine evolution. [ABSTRACT FROM AUTHOR]