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Presents a study which proposed a transient security dispatch which optimizes the transient behavior of a set of contingencies related to electric power systems. Development of an algorithm for transient security dispatch for multiple contingencies; Test results of feasibility of the proposal.

Deals with a study on the development of a non-linear programming methodology for evaluating corrective actions to improve the dynamic security of power systems when transient instability is detected. Representation of the proposed Unified Power Flow Controllers; Corrective control architecture of the emergency control system; Methods in mathematical formulation.

Evaluates the Marxian concept on industrial reserve army on increase economic. Discussions on the survey for the labor market; Effects of liberation to international trade; Increase availability on the laborforce from labor market population.

The high penetration of renewable energy sources, combined with a limited possibility to expand the transmission infrastructure, stretches the system stability in the case of faults. For this reason, operators are calling for additional control flexibility in the grid. In this paper, we propose the deployment of switchable reactors and capacitors distributed on the grid as a control resource for securing operations during severe contingencies and avoiding potential blackouts. According to the operating principles, the line reactance varies by switching on or off a certain number of distributed series reactors and capacitors and, therefore, the stabilizing control rule is based on a stepwise time-discrete control action. A control strategy, based on dynamic optimization, is proposed and tested on a realistic-sized transmission system. [ABSTRACT FROM AUTHOR]

Power system decarbonization will be one of the main challenges confronting society over the next twenty to thirty years. Renewable energy sources (RES), such as wind and solar, will be the main resources supplying the power grid. Given their volatility, their integration into the grid necessitates planning and utilizing new flexibility options. Energy storage systems (ESS), multi-energy systems and active consumer involvement are three solutions attracting the scientific community's attention. Data centers (DCs) provide a very high degree of flexibility for consumers. They can be utilized to support system operators or integrate power generated by locally installed renewable energy source generators in the DC's network. This study is intended to contribute by developing a methodology for planning new flexibility options in DCs. The methodology developed treats DCs as active multi-energy systems. Control strategies were also developed. The technical and economic performance of the solutions implemented was evaluated. [ABSTRACT FROM AUTHOR]

In this this paper, the optimal sizing of electric and thermal storage is applied to the novel definition of a net zero multi energy system (NZEMS). A NZMES is based on producing electricity exclusively from renewable energy sources (RES) and converting it into other energy forms to satisfy multiple energy needs of a community. Due to the intermittent nature of RES, storage resources are needed to increase the self-sufficiency of the system. Possible storage sizing choices are examined considering, on an annual basis, the solution of a predictive control problem aimed at optimizing daily operation. For each day of the year, a predictive control problem is formulated and solved, aimed at minimizing operating costs. Electric, thermal, and (electric) transportation daily curves and expected RES production are assessed by means of a model that includes environmental parameters. Test results, based on the energy model of a small rural village, show expected technical-economic performance of different planning solutions, highlighting how the renewable energy mix influences the choice of both thermal and electric storage, and how self-sufficiency can affect the overall cost of energy. [ABSTRACT FROM AUTHOR]

The paper describes the methodology used for developing an electric load microforecasting module to be integrated in the Energy Management System (EMS) architecture designed and tested within the "Energy Router" (ER) project. This Italian R&D project is aimed at providing non-industrial active customers and prosumers with a monitoring and control device that would enable demand response through optimization of their own distributed energy resources (DERs). The optimal control of resources is organized with a hierarchical control structure and performed in two stages. A cloud-based computation platform provides global control functions based on model predictive control whereas a closed-loop local device manages actual monitoring and control of field components. In this architecture, load forecasts on a small scale (a single residential or tertiary building) are needed as inputs of the predictive control problem. The microforecasting module aimed at providing such inputs was designed to be flexible, adaptive, and able to treat data with low time resolution. The module includes alternative forecasting techniques, such as autoregressive integrated moving average (ARIMA), neural networks, and exponential smoothing, allowing the application of the right forecasting strategy each time. The presented test results are based on a dataset acquired during a monitoring campaign in two pilot systems, installed during the ER Project in public buildings. [ABSTRACT FROM AUTHOR]

In this paper, correlation between uncertainties related to loads is addressed in transmission network expansion planning (TNEP). The TNEP problem is formulated in a multi-objective form with objective functions of minimum investment cost, minimum congestion cost, and minimum risk cost. Load correlation is modeled using unscented transformation method and compared to a simulation method. Initially, the impact of load correlation on congestion cost and risk cost is shown. Then, using the Pareto solutions of this multi-objective TNEP problem, impact of load correlation on the TNEP solutions is illustrated. The Pareto solutions are obtained using the Non-dominated Sorting Genetic Algorithm II (NSGA II) that is capable in handling non-convex and non-linear problems with mixed integer structures. Test results are provided for the IEEE 24-bus Reliability Test System (RTS) and a representation of the actual Iranian 400 kV transmission network. [ABSTRACT FROM AUTHOR]

Equisetum hyemale is used in traditional medicine as an anti-inflammatory, antioxidant, diuretic and anticancer agent. Recent studies have observed antiproliferative activity of this species in some tumor cell lines. The aim of this study was to evaluate the antiproliferative activity of the ethanol extract of E. hyemale and its partitions in oral squamous carcinoma cell lines, the death pathways induced by the most active partition, the acute toxicity and therapeutic activity, and the identification of the main compounds. The ethanol crude extract was prepared from the stems of E. hyemale and partitions were obtained from this extract with n -hexane, dichloromethane and ethyl acetate. Cytotoxicity assays were performed using MTT on human oral tumor lines SCC-9, SCC4 and SCC-25, and normal primary fibroblasts. The main pathways of programmed cell death were analyzed. Acute toxicity in mice was performed using the most active partition, ethyl acetate. Antitumor activity was accessed in xenotransplants grafts of SCC-9 cells in Balb/nude mice. Phytochemical analysis was performed using UHPLC-MS/MS and dereplication was done using Global Natural Product Social Molecular Networking (GNPS) analysis. Ethanol extract, n -hexane and ethyl acetate partitions showed dose-dependent activity and selectivity towards oral tumor cells, with the ethyl acetate being the most bioactive. This medium polarity partition was shown to induce tumor cell death through apoptosis due to the presence of activated caspase 3/7, DNA fragmentation, chromatin condensation and phosphatidylserine exposure. The ethyl acetate partition also produced low toxicity in mice, provoking mild hepatic changes, but without causing necrosis and significantly reduced tumors volume and weight in xenotransplants of SCC-9 cells. Phytochemical analysis allowed identification of kaempferol glycosides and cinnamic acid derivatives previously described for E. hyemale. In addition it was possible to identify 6 new non-glycolyzed flavonoids 5-Hydroxy-3′,4′,7,8-tetramethoxyflavone (14), 5,4′-Dihydroxy-7,8,3′-trimethoxyflavone (15), 5,7-Dihydroxy-3′,4′-dimethoxyflavone (16), 3′,4,5,7-Tretramethoxyflavone (17), 5-Hydroxy-3′4′,7-trimethoxyflavone (18), and 5,4′-Dihydroxy-3′-7′-dimethoxyflavone (19); besides 5 compounds already determined to be cytotoxic in other species, Isoferulic acid (1), Ferulic acid (2), Atractylenolide III (6), Dihydroxy-3′,4′-dimethoxyflavone (16), and 5-Hydroxy-3′4 ′,7-trimethoxyflavone (18). The results indicate that the E. hyemale extract and partitions inhibited 3 different cell lines of OSCC in a highly selective nontoxic way by inducing apoptosis of the cells. We identified 6 new non-glycosylated flavonoids and 5 other substances in this species. [Display omitted] • Equisetum hyemale extract show high cytotoxicity and selectivity toward cancer cells. • E. hyemale dichloromethane partition induces cell death via apoptosis. • Significant reduction in tumor growth in mice induced by E. hyemale partition. • Several substances being identified for the first time in this species. [ABSTRACT FROM AUTHOR]

On 25 January 2019, Córrego do Feijão's tailing dam at Brumadinho city (Minas Gerais, Brazil) breached, leaving over 250 people dead. At least 12 million cubic meters of ore tailing were spread into Paraopeba River and the surrounding area. To evaluate the short-term impacts of the Brumadinho dam rupture on the environment, we performed biogeochemical, microbiological and ecotoxicological analyses across 464 km of the Paraopeba River in the week following the disaster (1 February 2019) and four months latter (27–29 May 2019). Immediately after the disaster, the water turbidity was 3000 NTU, 30 times greater than the standard recommended by the Brazilian Resolution for Water Quality (CONAMA 357). Up to a 60-fold increase in iron tolerant microbial colony forming unities was observed up to 115 km downstream of the dam failure in May 2019 (compared with February 2019), suggesting changes in microbial metabolic profiles. In the second sampling (May 2019), the ecotoxicological analyses indicate higher zebrafish embryo mortality (up to ~85% embryo mortality) rates in Retiro Baixo (304 km from dam failure location). However, increased zebrafish mortality in Retiro Baixo and Três Marias reservoirs may not be related exclusively to the dam failure. The causal nexus of mortality may be associated with other factors (e.g. local sewage pollution). Our study suggests that independent monitoring programs are needed to quantify the extent of potential impacts caused by the anthropogenic use of the river and to promote the recovery of the impacted area. Unlabelled Image • At least 12 million m3 of ore tailing were spread into Paraopeba River. • High water turbidity, metal and nutrient levels were found after the disaster. • Increase Iron in Angueretá, 242 km downstream from the Brumadinho dam failure • Increase in iron tolerant bacteria in May 2019 • High zebrafish embryo mortality (up to 75%) in May 2019 [ABSTRACT FROM AUTHOR]

Objective: To assess the complications in patients with severe slipped capital femoral epiphysis treated with the Dunn or modified Dunn procedure from 2012 to 2018 at the Institute of Orthopedics and Traumatology, Medical School, Universidade de São Paulo., Methods: Analysis of medical records, preoperative and postoperative radiographs with at least one year of radiographic follow-up of patients with severe slipped capital femoral epiphysis., Results: We reviewed the complications in 19 operated cases from 2012 to 2018, out of which 36.8% had osteonecrosis of the femoral head, one patient had chondrolysis, and another had postoperative infection., Conclusion: The osteonecrosis rate observed in this series of cases is similar to that described in other orthopedic facilities. We assessed factors that could potentially influence this outcome, including other characteristics of the patient (obesity, endocrine diseases, and history of sports activities) and of the health system. Level of Evidence III, Restropective Case Series. , Competing Interests: All authors declare no potential conflict of interest related to this article.

We aimed to characterize the age of onset of training, age at menarche, menstrual periodicity, and performance perception during the menstrual cycle and examined the impact of these reproductive variables on body composition, morphology, and body weight satisfaction in Brazilian elite futsal players. The study consisted of 115 female Brazilian elite futsal players from the top national teams. Data were collected during the twentieth Women's Brazil Futsal Cup. Players were interviewed and self-reported their age of onset of training, age at menarche, menstrual periodicity, and the menstrual period, where they performed best. We also asked for what they considered to be their ideal body weight as well as information related to their training (i.e., volume and frequency). Subsequently, anthropometric measurements (i.e., body mass, height, circumferences, diameters, and skinfold thickness) were performed to estimate the body composition and determine morphological characteristics (e.g., somatotype). Fifty-nine (53.2%) players were postmenarche-trained and 52 (46.8%) were premenarche-trained. Eighteen (16.2%), 65 (58.6%), and 28 (25.2%) were classified as early, normal, and late menarche, respectively. Only 11 (9.6%) and 1 (0.9%) had irregular menstrual cycles and were amenorrheic, respectively. Seventy-three (69.5%), 23 (21.9%), and 9 (8.6%) reported that their game performance was the best at the follicular phase, menses, and luteal phase of the menstrual cycle, respectively. No associations between the four reproductive-related variables were found. Postmenarche-trained players had significant lower age at menarche and higher percentage body fat. The somatotype profile registered lower ectomorphy rate for the postmenarche-trained participants after controlling for covariates. Early menarche group presented higher sum of six skinfold thickness and endomorphy rate compared to normal and late menarche groups. No differences were found when menstrual periodicity groups and best performance groups were compared, except for higher femur width in the regular menstrual cycle group compared to the irregular one. The association between body weight satisfaction and the four reproductive-related variables were not observed. Premenarche-trained Brazilian elite futsal players had the menarche later than the postmenarche-trained athletes. Most of the participants had menarche age classified as "normal," presented "regular" menstrual cycles and perceived to perform better during the follicular phase of the menstrual cycle., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2021 Queiroga, da Silva, Ferreira, Weber, Fernandes, Cavazzotto, Portela, Tartaruga, Nascimento and Vieira.)

Background: Sedentary behavior is a risk factor for several diseases, while physically active lifestyles and physical fitness contribute to the promotion and maintenance of health., Objective: To establish the level of physical activity of university administrative employees and investigate its relationship with muscle strength indicators and morphological characteristics., Methods: The sample comprised 44 university administrative employees. Data on body mass (BM) and height were collected to calculate the body mass index. The participants' level of physical activity was established based on the International Physical Activity Questionnaire (IPAQ). The participants were subjected to four muscle strength tests: right hand grip (RHG), left hand grip (LHG), lumbar traction (LT) and lower limb traction (LLT). Relative muscle strength (%MS) was calculated dividing absolute muscle strength (AMS=RHG+LHG+LT+LLT) by BM., Results: The insufficiently active participants exhibited significant higher BM, lower LT, LLT, AMS and %MS, and spent more time in sedentary activities on weekends., Conclusion: Physical inactivity was associated with poorer muscle strength indicators and higher BM among university administrative employees, pointing to harms inherent to sedentary behavior.

Unplanned oil spills during offshore production are a serious problem for the industry and the marine environment. Here, we present the genome sequence analysis of three novel hydrocarbon-degrading bacteria, namely, " Candidatus Colwellia aromaticivorans" sp. nov., " Candidatus Halocyntiibacter alkanivorans" sp. nov., and " Candidatus Ulvibacter alkanivorans" sp. nov., (Copyright © 2019 Campeão et al.)

Objective: To retrospectively evaluate the preliminary postoperative results of modified Dega-type acetabular osteotomy to treat developmental dysplasia of the hip, confirming the efficacy and reproducibility of this technique., Methods: This retrospective study included patients older than 18 months. A total of 19 hips underwent modified Dega osteotomy., Results: Satisfactory results were obtained, with an average decrease of the acetabular index from 39.2 to 20.6 degrees. The final average center edge angle was 29.6 degrees. Hip joint congruence was reestablished in all cases, and as of this writing, only one case developed necrosis in the femoral head during follow-up., Conclusion: Modified Dega osteotomy demonstrated good initial results, as well as the potential for use in treating developmental dysplasia of the hip. Level of Evidence IV; Case series., Competing Interests: All authors declare no potential conflict of interest related to this article.

Objective: : This retrospective study evaluated treatment with individually contoured molded bracing at early stages of the disease., Methods: : We evaluated the medical records of patients undergoing treatment of Blount's disease with molded orthoses for medial decompression between 2010 and 2014. The deformity angle (Drennan's metaphyseal-diaphyseal angle) and Langenskiöld classification were measured before and after treatment by a pediatric orthopedic surgeon with over 5 years of practice, blinded for the study and patients., Results: : The mean age was 2.57 years old. Four patients were female and six male. Half of the total sample had bilateral disease. The average deformity angle showed a statistically significant reduction after treatment (p <0.001). Gender and laterality did not statistically influence the change of the deformity angle after treatment (p> 0.05)., Conclusion: : The nightly use of molded orthoses for medial decompression was effective in reducing the metaphyseal-diaphyseal angle in Blount's disease in children under 3 years of age, regardless of gender and bilateral disease. Patients over 3 years old did not benefit from bracing. Level of Evidence IV, Case Series.

Objective: : To investigate the slope influence on the maximal subtalar pronation in submaximal running speeds., Methods: : Sixteen endurance runners participated of a running economy (RE) test in a treadmill with different slopes (+1%, +5%, +10%, +15%). For each slope a 4-minute run was performed with no rest break for the purpose of measuring the magnitude of kinematic variables by means of a high frequency video camera positioned in a frontal-posterior plane of the individual., Results: : No significant differences were verified in maximal subtalar pronation between legs and between the slopes adopted, showing that changes of running technique due to modifications of slope aren't enough to modify the behavior of maximum subtalar pronation., Conclusion: : The subtalar pronation is independent of slope, which may be influenced by other intervening variables. Level of Evidence II, Diagnostic Study.

Vibrio campbellii PEL22A was isolated from open ocean water in the Abrolhos Bank. The genome of PEL22A consists of 6,788,038 bp (the GC content is 45%). The number of coding sequences (CDS) is 6,359, as determined according to the Rapid Annotation using Subsystem Technology (RAST) server. The number of ribosomal genes is 80, of which 68 are tRNAs and 12 are rRNAs. V. campbellii PEL22A contains genes related to virulence and fitness, including a complete proteorhodopsin cluster, complete type II and III secretion systems, incomplete type I, IV, and VI secretion systems, a hemolysin, and CTXΦ.