Identification of Linearized RMS-Voltage Dip Patterns Based on Clustering in Renewable Plants

[EN] Generation units connected to the grid are currently required to meet low-voltage ride-through (LVRT) requirements. In most developed countries, these requirements also apply to renewable sources, mainly wind power plants and photovoltaic installations connected to the grid. This study proposes an alternative characterisation solution to classify and visualise a large number of collected events in light of current limits and requirements. The authors' approach is based on linearised root-mean-square-(RMS)-voltage trajectories, taking into account LRVT requirements, and a clustering process to identify the most likely pattern trajectories. The proposed solution gives extensive information on an event's severity by providing a simple but complete visualisation of the linearised RMS-voltage patterns. In addition, these patterns are compared to current LVRT requirements to determine similarities or discrepancies. A large number of collected events can then be automatically classified and visualised for comparative purposes. Real disturbances collected from renewable sources in Spain are used to assess the proposed solution. Extensive results and discussions are also included in this study.The authors thank the financial support from the 'Ministerio de Economia y Competitividad' (Spain) and the European Union - ENE2016-78214-C2-2-R, Fulbright/Spanish Ministry of Education Visiting Scholar - PRX14/00694. This work was also supported by the US Department of Energy under contract no. DE-AC36-08-GO28308 with the National Renewable Energy LaboratoryGarcía-Sánchez, TM.; Gómez-Lázaro, E.; Muljadi, E.; Kessler, M.; Muñoz-Benavente, I.; Molina-García, A. (2018). Identification of Linearized RMS-Voltage Dip Patterns Based on Clustering in Renewable Plants. IET Generation Transmission & Distribution. 12(6):1256-1262. https://doi.org/10.1049/iet-gtd.2017.0474S12561262126Craciun B. Kerekes T. 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Enhancing Biopharmaceutical Attributes of Phospholipid Complex-loaded Nanostructured Lipidic Carriers of Mangiferin: Systematic Development, Characterization and Evaluation

Mangiferin (Mgf), largely expressed out from the leaves and stem bark of Mango, is a potent antioxidant. However, its in vivo activity gets tremendously reduced owing to poor aqueous solubility and inconsistent gastrointestinal absorption, high hepatic first-pass metabolism and high P-gp efflux. The current research work, therefore, was undertaken to overcome the biopharmaceutical hiccups by developing the Mgf-phospholipid complex (PLCs) loaded in nanostructured lipidic carriers (NLCs). The PLCs and NLCs were prepared using refluxing, solvent evaporation and hot emulsification technique, respectively with various molar ratios of Mgf and Phospholipon 90 G, i.e., 1:1; 1:2; and 1:3. The complex was evaluated for various physicochemical parameters like drug content (96.57%), aqueous solubility (25-fold improved) and oil-water partition coefficient (10-fold enhanced). Diverse studies on the prepared complex using FTIR, DSC, PXRD and SEM studies ratified the formation of PLCs at 1:1 ratio. The PLCs were further incorporated onto NLCs, which were systematically optimized employing a face centered cubic design (FCCD), while evaluating for particle size, zeta potential, encapsulation efficiency and in vitro drug release as the CQAs. Caco-2 cell line indicated insignificant cytotoxicity, and P-gp efflux, bi-directional permeability model and in situ perfusion studies specified enhanced intestinal permeation parameters. In vivo pharmacokinetic studies revealed notable increase in the values of Cmax (4.7-fold) and AUC (2.1-fold), respectively, from PLCs-loaded NLCs vis-à-vis Mgf solution. In a nutshell, the promising results observed from the present research work signified boosted biopharmaceutical potential of the optimized PLCs-loaded NLCs for potentially augmenting the therapeutic efficacy of Mgf

Transcriptomic analysis of lignocellulosic biomass degradation by the anaerobic fungal isolate Orpinomyces sp. strain C1A

Background: Anaerobic fungi reside in the rumen and alimentary tract of herbivores where they play an important role in the digestion of ingested plant biomass. The anaerobic fungal isolate Orpinomyces sp. strain C1A is an efficient biomass degrader, capable of simultaneous saccharification and fermentation of the cellulosic and hemicellulosic fractions in multiple types of lignocellulosic biomass. To understand the mechanistic and regulatory basis of biomass deconstruction in anaerobic fungi, we analyzed the transcriptomic profiles of C1A when grown on four different types of lignocellulosic biomass (alfalfa, energy cane, corn stover, and sorghum) versus a soluble sugar monomer (glucose).Results: A total of 468.2 million reads (70.2 Gb) were generated and assembled into 27,506 distinct transcripts. CAZyme transcripts identified included 385, 246, and 44 transcripts belonging to 44, 13, and 8 different glycoside hydrolases (GH), carbohydrate esterases, and polysaccharide lyases families, respectively. Examination of CAZyme transcriptional patterns indicates that strain C1A constitutively transcribes a high baseline level of CAZyme transcripts on glucose. Although growth on lignocellulosic biomass substrates was associated with a significant increase in transcriptional levels in few GH families, including the highly transcribed GH1 B-glucosidase, GH6 cellobiohydrolase, and GH9 endoglucanase, the transcriptional levels of the majority of CAZyme families and transcripts were not significantly altered in glucose-grown versus lignocellulosic biomass-grown cultures. Further, strain C1A co-transcribes multiple functionally redundant enzymes for cellulose and hemicellulose saccharification that are mechanistically and structurally distinct. Analysis of fungal dockerin domain-containing transcripts strongly suggests that anaerobic fungal cellulosomes represent distinct catalytic units capable of independently attacking and converting intact plant fibers to sugar monomers.Conclusions: Collectively, these results demonstrate that strain C1A achieves fast, effective biomass degradation by the simultaneous employment of a wide array of constitutively-transcribed cellulosome-bound and free enzymes with considerable functional overlap. We argue that the utilization of this indiscriminate strategy could be justified by the evolutionary history of anaerobic fungi, as well as their functional role within their natural habitat in the herbivorous gut.Peer reviewedMicrobiology and Molecular Genetic

Improvement of cooperation skills of middle school children in games in a pre-school educational institution

Kvalifikācijas darba autors: Renāte Lopesa Darba nosaukums: “Vidējā pirmsskolas vecuma bērnu sadarbības prasmju pilnveidošana rotaļās pirmsskolas izglītības iestādē” Darba mērķis: teorētiski analizēt un praktiski pētīt vidējā pirmsskolas vecuma bērnu sadarbības prasmes un atbilstošu rotaļu ietekmi uz šo spēju pilnveidi. Darbs sastāv no ievada, teorētiskās daļas, kurā tiek analizētas pedagoģijas un psiholoģijas zinātnieku atziņas par sadarbības prasmju nozīmi un vidējā pirmsskolas vecuma bērnu sadarbības prasmju īpatnības, kā arī teorētiski pamatots, vai un kāpēc rotaļas ir atbilstošs instruments sadarbības prasmju pilnveidošanai vidējā pirmsskolas vecuma bērniem, raksturojot atbilstoši piemeklētās rotaļas, un pētījuma empīriskās daļas. Empīriskajā daļā tika veikts praktiskais pētījums X pirmsskolas izglītības iestādes vidējā pirmsskolas vecuma grupā 17 bērnu sastāvā. Sākotnēji kopā ar diviem dotās grupas pirmsskolas skolotājiem tika veikts bērnu raksturojums un definēto sadarbības prasmju izvērtējums pētījuma sākumā. Pēc tam viena mēneša garumā šajā grupā tika mērķtiecīgi izmantotas atbilstoši piemeklētās spēles un rotaļas, kas vērstas uz dažādu sadarbības prasmju pilnveidošanu pirmsskolas izglītības iestādē. Pētījuma noslēgumā tika veikts atkārtots prasmju izvērtējums, kas ļāva secināt, ka izvirzītā hipotēze tiek apstiprināta, un pirmsskolas izglītības iestādē mērķtiecīgi izmantojot atbilstoši piemeklētas rotaļas, ir iespējams pilnveidot vidējā pirmsskolas vecuma bērnu sadarbības prasmes. Darbs izstrādāts uz 42 lapaspusēm, tajā ievietoti 5 attēli, 3 tabulas, izmantoti 35 literatūras un citi avoti. Atslēgas vārdi: vidējais pirmsskolas vecums; sadarbības prasmes; caurvijas; rotaļas; rotaļnodarbības.Author of the qualification paper: Renate Lopesa Title of the paper: “Improvement of cooperation skills of middle preschool age children in games in pre-school educational institution” Aim of the research: to theoretically analyze and practically study the cooperation skills of middle preschool age children and the influence of appropriate games on the development of these abilities. Research consists of: introduction, theoretical part which analyzes the findings of pedagogical and psychological scientists on the importance of cooperation skills and the peculiarities of cooperation skills of middle preschool age children, as well as theoretically substantiated whether and why games are an appropriate tool for developing cooperation skills in middle preschool age children, describing the appropriately selected games, and the empirical part of the study. In the empirical part, a practical study was performed in the middle preschool age group of X pre-school educational institution with 17 children. Initially, characteristics of the children were defined and assessment of the particular cooperation skills at the beginning of the study was performed together with the two pre-school teachers of the group. After that, various appropriately selected games, aimed at improving different cooperation skills in the preschool educational institution, were purposefully used in everyday life of this group for one month. At the end of the study, a re-assessment of initial skills was performed, which allowed to conclude that the hypothesis is confirmed, and using appropriately selected games in preschool education institutions purposefully can improve the cooperation skills of middle preschool age children. The paper contains 42 pages, 5 figures and 3 tables, 35 literature and other sources. Keywords: middle preschool age children; cooperation skills; games; play

Resources and technologies in Social Occupational Therapy: actions with the poor youth in town

The METUIA team from the Occupational Therapy Department of the Federal University of Sao Carlos – UFSCar has been elaborating procedures and resources, which have produced contributions to the action of occupational therapy based on a local and communal dimension, aiming at a locally rooted technical contribution and directed to face the challenges of the social field. The territory notion adopted presupposes historical, economic, social and cultural dimensions that contextualize a given geographical area where the therapeutic and occupational action is developed. We have been dealing with questions related to the poor urban youth and working in the production of social technologies (understood as products, techniques or replicable methodologies developed in interaction with the community, and that represent alternatives for social transformation), which have been able to foster new possibilities of action, integrating and articulating actions of macro and micro social scope. This article presents discussions on Workshops of Dynamics, Activities and Projects; Individual and Territorial Follow-up; Articulation of Resources in the Social Field; and Dynamization of the Social Care Network. We support a continuous and critical reflection on the labor process, assuming the technical, ethical and political dimensions that comprise the professional qualification of occupational therapists. We also advocate that the practical and conceptual existence of these technologies promotes actions associated with the social question of the lives of these young individuals, seeking the expansion of equality, recognition of differences, and their space in the public sphere, so that more participation can be produced with more freedom, autonomy and solidarity

Boletín del Servicio Meteorológico Español: Año XXXVII Número 257 - 1929 Septiembre 13

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Model-Preserving, Scalable Runtime Patches

Abstract. We consider a methodology for flexible software design, runtime programming, defined by recurrent, incremental software modifications to a program at runtime, called runtime patches. The principles we consider for runtime programming are model preservation, ensuring the model in place for programs is preserved whilst allowing for runtime patches, and scalability, understanding how program compilation can appropriately scale in proportion to the change induced by a runtime patch. In accordance, a runtime patch is proposed as a modelpreserving operation, working as a correct instantaneous transition between programs, and one that can be incrementally compiled for scalability. We put the formulation in perspective through a case-study instantiation over a language for distributed hard real-time systems, the Hierarchical Timing Language (HTL).