bluuebunny/crossref_metadata_2025 huggingface dataset:
Modeling and Optimization of Gaseous Thermal Slip Flow in Rectangular Microducts Using a Particle Swarm Optimization Algorithm
Authors: Hamadneh Nawaf N. , Khan Waqar A. , Khan Ilyas , Alsagri Ali S.
Published: April 2019

In this study, pressure-driven flow in the slip regime is investigated in rectangular microducts. In this regime, the Knudsen number lies between 0.001 and 0.1. The duct aspect ratio is taken as 0 ≤ ε ≤ 1 . Rarefaction effects are introduced through the boundary conditions. The dimensionless governing equations are solved numerically using MAPLE and MATLAB is used for artificial neural network modeling. Using a MAPLE numerical solution, the shear stress and heat transfer rate are obtained. The numerical solution can be validated for the special cases when there is no slip (continuum flow), ε = 0 (parallel plates) and ε = 1 (square microducts). An artificial neural network is used to develop separate models for the shear stress and heat transfer rate. Both physical quantities are optimized using a particle swarm optimization algorithm. Using these results, the optimum values of both physical quantities are obtained in the slip regime. It is shown that the optimal values ensue for the square microducts at the beginning of the slip regime.
A New Topical Eye Drop Containing LyeTxI-b, A Synthetic Peptide Designed from A Lycosa erithrognata Venom Toxin, Was Effective to Treat Resistant Bacterial Keratitis
Authors: Silva Carolina Nunes da , Silva Flavia Rodrigues da , Dourado Lays Fernanda Nunes , Reis Pablo Victor Mendes dos , Silva Rummenigge Oliveira , Costa Bruna Lopes da , Nunes Paula Santos , Amaral Flávio Almeida , Santos Vera Lúcia dos , de Lima Maria Elena , Silva Cunha Júnior Armando da
Published: April 2019

Bacterial keratitis is an ocular infection that can lead to severe visual disability. Staphylococcus aureus is a major pathogen of the eye. We recently demonstrated the strong antimicrobial activity of LyeTxI-b, a synthetic peptide derived from a Lycosa erithrognatha toxin. Herein, we evaluated a topical formulation (eye drops) containing LyeTxI-b to treat resistant bacterial keratitis. Keratitis was induced with intrastromal injection of 4 × 105 cells (4 µL) in New Zealand female white rabbits. Minimum inhibitory concentration (MIC) and biofilm viability were determined. LyeTxI-b ocular toxicity was evaluated through chorioallantoic membrane and Draize tests. One drop of the formulation (LyeTxI-b 28.9 µmol/L +0.5% CMC in 0.9% NaCl) was instilled into each eye four times a day, for a week. Slit-lamp biomicroscopy analysis, corneal histopathological studies and cellular infiltrate quantification through myeloperoxidase (MPO) and N-acetylglucosaminidase (NAG) detection were performed. LyeTxI-b was very effective in the treatment of keratitis, with no signs of ocular toxicity. Planktonic bacteria MIC was 3.6 µmol/L and LyeTxI-b treatment reduced biofilm viability in 90%. LyeTxI-b eliminated bacteria and reduced inflammatory cellular activity in the eyes. Healthy and treated animals showed similar NAG and MPO levels. LyeTxI-b is a potent new drug to treat resistant bacterial keratitis, showing effective antimicrobial and anti-inflammatory activity.
Interpreting Viral Deep Sequencing Data with GLUE
Authors: Singer Joshua B. , Thomson Emma C. , Hughes Joseph , Aranday-Cortes Elihu , McLauchlan John , da Silva Filipe Ana , Tong Lily , Manso Carmen F. , Gifford Robert J. , Robertson David L. , Barnes Eleanor , Ansari M. Azim , Mbisa Jean L. , Bibby David F. , Bradshaw Daniel , Smith David
Published: April 2019

Using deep sequencing technologies such as Illumina’s platform, it is possible to obtain reads from the viral RNA population revealing the viral genome diversity within a single host. A range of software tools and pipelines can transform raw deep sequencing reads into Sequence Alignment Mapping (SAM) files. We propose that interpretation tools should process these SAM files, directly translating individual reads to amino acids in order to extract statistics of interest such as the proportion of different amino acid residues at specific sites. This preserves per-read linkage between nucleotide variants at different positions within a codon location. The samReporter is a subsystem of the GLUE software toolkit which follows this direct read translation approach in its processing of SAM files. We test samReporter on a deep sequencing dataset obtained from a cohort of 241 UK HCV patients for whom prior treatment with direct-acting antivirals has failed; deep sequencing and resistance testing have been suggested to be of clinical use in this context. We compared the polymorphism interpretation results of the samReporter against an approach that does not preserve per-read linkage. We found that the samReporter was able to properly interpret the sequence data at resistance-associated locations in nine patients where the alternative approach was equivocal. In three cases, the samReporter confirmed that resistance or an atypical substitution was present at NS5A position 30. In three further cases, it confirmed that the sofosbuvir-resistant NS5B substitution S282T was absent. This suggests the direct read translation approach implemented is of value for interpreting viral deep sequencing data.
Characterization of the RNA Transcription Profile of Bombyx mori Bidensovirus
Authors: Li Rui , Chang Pengfei , Lü Peng , Hu Zhaoyang , Chen Keping , Yao Qin , Yu Qian
Published: April 2019

Bombyx mori bidensovirus (BmBDV) is a single-stranded DNA (ssDNA) virus from the genus Bidensovirus of the Bidnaviridae family, which, thus far, solely infects insects. It has a unique genome that contains bipartite DNA molecules (VD1 and VD2). In this study, we explored the detailed transcription mapping of the complete BmBDV genome (VD1 and VD2) by rapid amplification of cDNA ends (RACE), reverse transcription quantitative real-time PCR (RT-qPCR), and luciferase assays. For the first time, we report the transcription map of VD2. Our mapping of the transcriptional start sites reveals that the NS genes in VD1 have separate transcripts that are derived from overlapping promoters, P5 and P5.5. Thus, our study provides a strategy for alternative promoter usage in the expression of BmBDV genes.
Mechanism of Inhibition of Ebola Virus RNA-Dependent RNA Polymerase by Remdesivir
Authors: Tchesnokov Egor P. , Feng Joy Y. , Porter Danielle P. , Götte Matthias
Published: April 2019

Remdesivir (GS-5734) is a 1′-cyano-substituted adenosine nucleotide analogue prodrug that shows broad-spectrum antiviral activity against several RNA viruses. This compound is currently under clinical development for the treatment of Ebola virus disease (EVD). While antiviral effects have been demonstrated in cell culture and in non-human primates, the mechanism of action of Ebola virus (EBOV) inhibition for remdesivir remains to be fully elucidated. The EBOV RNA-dependent RNA polymerase (RdRp) complex was recently expressed and purified, enabling biochemical studies with the relevant triphosphate (TP) form of remdesivir and its presumptive target. In this study, we confirmed that remdesivir-TP is able to compete for incorporation with adenosine triphosphate (ATP). Enzyme kinetics revealed that EBOV RdRp and respiratory syncytial virus (RSV) RdRp incorporate ATP and remdesivir-TP with similar efficiencies. The selectivity of ATP against remdesivir-TP is ~4 for EBOV RdRp and ~3 for RSV RdRp. In contrast, purified human mitochondrial RNA polymerase (h-mtRNAP) effectively discriminates against remdesivir-TP with a selectivity value of ~500-fold. For EBOV RdRp, the incorporated inhibitor at position i does not affect the ensuing nucleotide incorporation event at position i+1. For RSV RdRp, we measured a ~6-fold inhibition at position i+1 although RNA synthesis was not terminated. Chain termination was in both cases delayed and was seen predominantly at position i+5. This pattern is specific to remdesivir-TP and its 1′-cyano modification. Compounds with modifications at the 2′-position show different patterns of inhibition. While 2′-C-methyl-ATP is not incorporated, ara-ATP acts as a non-obligate chain terminator and prevents nucleotide incorporation at position i+1. Taken together, our biochemical data indicate that the major contribution to EBOV RNA synthesis inhibition by remdesivir can be ascribed to delayed chain termination. The long distance of five residues between the incorporated nucleotide analogue and its inhibitory effect warrant further investigation.
Hydraulic Oscillation and Instability of A Hydraulic System with Two Different Pump-Turbines in Turbine Operation
Authors: Palikhe Sunit , Zhou Jianxu , Bhattarai Khem Prasad
Published: April 2019

Hydraulic oscillation mainly reveals the undesirable pressure fluctuations which can cause catastrophic failure of any hydraulic system. The behavior of a hydraulic system equipped with two different pump-turbines was investigated through hydraulic oscillation analysis to demonstrate severe consequences induced in turbine operation, including S-shaped characteristics. The impedance of a pump-turbine has an essential role in the determination of the instability of the hydraulic system. The conventional way to determine the instability solely using the slope of a characteristic curve was improved, including the effect of guide vane opening in pump-turbine impedance, which consequently modified the instability expression. With this pump-turbine impedance, hydraulic oscillation analysis, including free oscillation analysis and frequency response analysis, was carried out. The free oscillation analysis entails the computation of complex natural frequencies and corresponding mode shapes of the system. These computations provided necessary information about the vulnerable position of vital hydraulic components and the scenario for self-excited oscillation. Further, the analysis illustrates the significant role of guide vane opening to prevent the system from becoming unstable. Lastly, frequency response analysis was performed for the system with an oscillating guide vane to obtain the frequency response spectrum, which revealed that the resonating frequencies are consistent with natural frequencies, and it supported free oscillation results.
Water-Worked Gravel Bed: State-of-the-Art Review
Authors: Padhi Ellora , Dey Subhasish , Desai Venkappayya R. , Penna Nadia , Gaudio Roberto
Published: April 2019

In a natural gravel-bed stream, the bed that has an organized roughness structure created by the streamflow is called the water-worked gravel bed (WGB). Such a bed is entirely different from that created in a laboratory by depositing and spreading gravels in the experimental flume, called the screeded gravel bed (SGB). In this paper, a review on the state-of-the-art research on WGBs is presented, highlighting the role of water-work in determining the bed topographical structures and the turbulence characteristics in the flow. In doing so, various methods used to analyze the bed topographical structures are described. Besides, the effects of the water-work on the turbulent flow characteristics, such as streamwise velocity, Reynolds and form-induced stresses, conditional turbulent events and secondary currents in WGBs are discussed. Further, the results form WGBs and SGBs are compared critically. The comparative study infers that a WGB exhibits a higher roughness than an SGB. Consequently, the former has a higher magnitude of turbulence parameters than the latter. Finally, as a future scope of research, laboratory experiments should be conducted in WGBs rather than in SGBs to have an appropriate representation of the flow field close to a natural stream.
A Review of Fouling Mechanisms, Control Strategies and Real-Time Fouling Monitoring Techniques in Forward Osmosis
Authors: Ibrar Ibrar , Naji Osamah , Sharif Adel , Malekizadeh Ali , Alhawari Alaa , Alanezi Adnan Alhathal , Altaee Ali
Published: April 2019

Forward osmosis has gained tremendous attention in the field of desalination and wastewater treatment. However, membrane fouling is an inevitable issue. Membrane fouling leads to flux decline, can cause operational problems and can result in negative consequences that can damage the membrane. Hereby, we attempt to review the different types of fouling in forward osmosis, cleaning and control strategies for fouling mitigation, and the impact of membrane hydrophilicity, charge and morphology on fouling. The fundamentals of biofouling, organic, colloidal and inorganic fouling are discussed with a focus on recent studies. We also review some of the in-situ real-time online fouling monitoring technologies for real-time fouling monitoring that can be applicable to future research on forward osmosis fouling studies. A brief discussion on critical flux and the coupled effects of fouling and concentration polarization is also provided.
SOFTWARE IMPLEMENTATION OF FINITE‐DIFFERENCE METHOD FOR PARAMETER IDENTIFICATION IN AGROECOLOGICAL MODELLING
Authors: Jushchenko N. , Denisov V.
Published: April 2019

A finite difference method for numerical solution of the inverse problem of heat transfer in a soil is described with an emphasis on algorithmic and software implementation issues. A mathematical package Matlab v.5.3 is chosen for the method implementation as it includes a number of matrix procedures with special measures for sparce matrices. Field experiments data obtained from the Lithuanian Institute of Agriculture are used to provide an input information and to calculate identification criteria at each iteration step. Typical numerical results of inverse problem solution and investigation of algorithm convergation process are presented and discussed in detail.
ON THE SELF-SIMILAR HEAT BOUNDARY LAYER PROBLEMS IN MAGNETOHYDRODYNAMICS
Authors: Kremenetsky V.
Published: April 2019

Usually all self‐similar heat boundary layer problems in presence of magnetic field are solved neglecting the Joule heat, created by current, induced in fluid by interaction of velocity and magnetic field. But the analysis of this heat shows that its influence to the temperature field is very important. For vertical flows it is impossible to find self‐similar solution of boundary layer problems due to the Joule heat influence in temperature field. For horizontal flows only two self‐similar boundary layer problems can be formulated: flow near the critical point in magnetic field with the neutral point and in the transverse steady magnetic field.
MATHEMATICAL MODELING OF WOOD DRYING PROCESS
Authors: Čiegis R. , Starikovičius V.
Published: April 2019

This work focuses on the development of mathematical models describing moisture movement in wood, when the wood is considered as porous medium. Main moisture transport mechanisms are discussed. It is shown how the wood can be described as a two‐ or three‐phase system. Summaries of several multiphase flow models are presented in the hierarchical order: from the most general models to more simple examples. The approximation steps are described explicitly, and all assumptions are given in detail. It shown how models for specific applications in wood drying or saturation can be obtained.
PROJECTION METHODS FOR INTEGRAL EQUATIONS IN EPIDEMIC
Authors: Hacia L.
Published: April 2019

In this paper numerical methods for mixed integral equations are presented. Studied equations arise in the mathematical modeling of the spatio‐temporal development of an epidemic. The general theory of these equations is given and used in the projection methods. Projection methods lead to a system of algebraic equations or to a system of Volterra integral equations. The considered theory is illustrated by numerical examples.
CELLULAR AUTOMATA AND ENERGETICS SYSTEM FORMATION
Authors: Šiugždaite R. , Norvaišas S.
Published: April 2019

Modeling complex systems requires to reduce, to organize the system complexity and to describe suitable components. Complexity of the system can then be tackled with an agentoriented approach, where local interactions lead to a global behavior. This approach helps to understand how non‐deterministic behavior that is near self‐organized criticality (SOC) is used to explain natural and social phenomena can emerge from local interactions between agents.

The basis of our decision to develop cellular automata (CA) as a model for energetics system formation and development in restricted region is its hypothetical dependence on and origin from the “urban slice” which is basis for “energetics slice”. In the urban CA model there we introduce five types of cells representing empty area, roads, houses, water and forest. Some types of cells are introduced only for the model better correspondence to the real system and don't have essentially influence to the modeling results. We assign all cell types certain weight, which affects the probability of new “houses” cells appearance replacing “empty area” cells. Usually all cells except the empty ones have much bigger weight, therefore the dynamic of houses distribution in restricted area is organized in clusters.

A first step in model ‘reliability’ is an understanding how these systems behave over time. CA's are an alternative to differential equations on an attempt to model these systems. One of the most important features of CA models is its desirable capacity to capture quantitative micro‐level dynamics and relate them to qualitative macro‐level behavior.

Energetics system formation is dynamic process that directly depends on houses conglomerate formation, energy production and transferring prices, energy consumption factor etc. Dynamical CA model can be used to realize certain purposes of energetic policy and to make decisions about volume of production as well as prices of generation and transmission. These decisions, in one's turn, influence successive urban and energetics system dynamics. There is analyzed how various policies influence urban system development as well as its stability after the new capacity is installed and prices in generation and transmission as well as system administration are changed, etc [3]. Also there is explored how energetics system dynamics obtained with help of dynamic model corresponds with CA obtained dynamics.
TACIT KNOWLEDGE AND FIRM PERFORMANCE RELATIONSHIP. THE ROLE OF PRODUCT INNOVATION AND THE FIRM LEVEL CAPABILITIES
Authors: López-Cabarcos M. Ángeles , Srinivasan Suresh , Göttling-Oliveira-Monteiro Sérgio , Vázquez-Rodríguez Paula
Published: April 2019

Based on knowledge-based theory of organizational capabilities and dynamic capabilities theory, this paper tries to establish the linkages between tacit knowledge resources, its integration into firm level capabilities, product innovation and firm performance. In this way, the paper analyses the relationships between some of the most relevant variables to the organizations in order to remain competitive. The conceptual model is tested using a sample of organizations in the industrial sector, using SEM and hierarchical regression analysis. Results show a positive relationship between tacit knowledge and firm performance, tacit knowledge and product innovation, and product innovation and firm performance. A partial mediating effect of product innovation on the tacit knowledge firm performance relationship is established. Also, technical capabilities have a moderator effect on tacit knowledge firm performance relationship. At the end of the paper managerial implications are commented, as well directions for future studies.
Megafire effects on spotted owls: elucidation of a growing threat and a response to Hanson et al. (2018)
Authors: Jones Gavin , Gutierrez Ralph , Tempel Douglas , Berigan William , Whitmore Sheila , Peery Zachariah
Published: April 2019

The extent to which wildfire adversely affects spotted owls (Strixoccidentalis) is a key consideration for ecosystem restoration efforts in seasonally dry forests of the western United States. Recently, Jones et al. (2016) demonstrated that the 2014 King Fire (a “megafire”) adversely affected a population of individually-marked California spotted owls (S.o.occidentalis) monitored as part of a long-term demographic study in the Sierra Nevada, California, USA because territory occupancy declined substantially at territories burned at high-severity and GPS-tagged spotted owls avoided large patches of high-severity fire. Hanson et al. (2018) attempted to reassess changes in territory occupancy of the Jones et al. (2016) study population and claimed that occupancy declined as a result of post-fire salvage logging not fire per se and suggested that the avoidance of GPS-marked owls from areas that burned at high-severity was due to post-fire logging rather than a response to high-severity fire. Here, we demonstrate that Hanson et al. (2018) used erroneous data, inadequate statistical analyses and faulty inferences to reach their conclusion that the King Fire did not affect spotted owls and, more broadly, that large, high-severity fires do not pose risks to spotted owls in western North American dry forest ecosystems. We also provide further evidence indicating that the King Fire exerted a clear and significant negative effect on our marked study population of spotted owls. Collectively, the additional evidence presented here and in Jones et al. (2016) suggests that large, high-severity fires can pose a threat to spotted owls and that restoration of natural low- to mixed-severity frequent fire regimes would likely benefit both old-forest species and dry forest ecosystems in this era of climate change. Meeting these dual objectives of species conservation and forest restoration will be complex but it is made more challenging by faulty science that does not acknowledge the full range of wildfire effects on spotted owls.
ENHANCED DYNAMIC THRESHOLD ALGORITHM OF QRS COMPLEX DETECTION
Authors: Liu Xiangyu , Wan Xiangkui , Xu Jun , Li Fengcong , Xu Zhengwang , Xiang Dingcheng
Published: April 2019

The dynamic threshold algorithm (DTA) presented by Pan Tompkins is a popular QRS detection method, and it has high sensitivity and specificity. However, the accuracy of this algorithm would be compromised if its sensitivity is increased. In this study, an enhanced dynamic threshold algorithm (EDTA) based on dynamic threshold rules is proposed, which add a compensation scheme to reduce the rate of misdetection and missed detection of R wave in low signal-to-noise ratio condition, sensitivity and detection error rate are calculated on simulated and clinical data to compare the performance between EDTA and DTA, and EDTA yields a competitive results. For the clinical data, the average accuracy rate of EDTA is 99.24%, which is higher than that of DTA at 95.98%. Further compared experiments among EDTA and the two other popular algorithms are conducted and the results of their validation over a public database are given and discussed, which prove our superiority.
A Novel Approach for the Customer Segmentation Using Clustering Through Self-Organizing Map
Authors: Barman Debaditya , Chowdhury Nirmalya
Published: April 2019

Customer segmentation is the process of forming smaller groups of customers according to their characteristics. Now companies can develop proper marketing strategies for each group to get the desired results. This type of direct marketing is practiced by most organizations from the size of smallest start-up to the Fortune 500 leaders. Clustering is the ideal data mining technique for customer segmentation. In this article, the authors have proposed a clustering algorithm based on the self-organizing map and minimum spanning tree for customer segmentation. The authors have used several synthetic and real-life datasets to evaluate the clustering performance of their approach. To demonstrate the effectiveness of the authors' proposed approach, they have trained few classifiers with the groups extracted from a direct marketing campaign of a Portuguese banking institution and show that the classification accuracy is better compared to the results obtained in some previous work where the full dataset has been used to train the same classifiers.
Knowledge Generation Using Sentiment Classification Involving Machine Learning on E-Commerce
Authors: Ghosh Swarup Kr , Dey Sowvik , Ghosh Anupam
Published: April 2019

Sentiment analysis manages the computational treatment of conclusion, notion, and content subjectivity. In this article, three sentiment classes such as positive, negative and neutral emotions have been demonstrated by appropriate features from raw unstructured data followed by data preprocessing steps. Applying best in class social analytics methodology to examine the sentiments embedded with purchaser remarks, encourages both producer and individual customers. Machine learning methods such as Naïve Bayes, maximum entropy classification, Deep Neural Networks were used upon the data, extracted from some websites such as Samsung and Apple for sentiment classification. In the online business arena, the application of sentiment classification explores a great opportunity. The subsidy of such an investigation is that associations can apply the proposed social examination framework to exploit the entire social information on the web and therefore improve their proper blueprint promoting strategies corresponding business.
Study on Traffic Multi-Source Data Fusion
Authors: Liu Suping , Zhang Dongbo , Li Jialin
Published: April 2019

In order to alleviate urban traffic congestion, it is necessary to obtain roadway network traffic flow parameters to estimate the traffic conditions. Single-detector data may not be sufficient to obtain a comprehensive, effective, accurate and high-quality traffic flow data. Neural networks and regression analysis data fusion methods are employed to expand data sources as well as for improving data quality. The multi-source detector data can provide fundamental support for traffic management. An empirical analysis was conducted using acquisition technology employed by the Beijing urban expressway to estimate traffic flow parameters. The results show that the proposed data fusion method is feasible and provides reliable data sources.
A protection technique for series capacitor compensated 400 kV double circuit transmission line based on wavelet transform including inter-circuit and cross-country faults
Authors: Kapoor Gaurav
Published: April 2019

In this paper, wavelet transform based technique is introduced to detect and classify the faults in a series capacitor compensated double circuit transmission line. The three phase currents of both circuits measured at only one end of the series compensated double circuit transmission line are used to calculate the approximate and high frequency detail coefficients including wavelet energy content of each phase current signal. To evaluate the performance of proposed fault detection technique, simulation studies have been carried out on a series capacitor compensated double circuit transmission line test system. The major advantage of this proposed scheme is that it offers protection to entire transmission line length using one end fault current data only. The test results prove that all types of faults are correctly detected and the faulty phase is accurately identified using proposed technique. This technique is robust to the variation in fault type, fault inception time, fault resistance, ground resistance and fault location.Keywords: Fault detection, fault classification, series capacitor compensated double circuit transmission line, wavelet transform
Optimization of biodiesel production from waste frying palm oil using definitive screening design
Authors: Rajesh Y , Kolakoti Aditya , Sheakar B.G. Chandra , Bhargavi J
Published: April 2019

Research on alternative fuels is increasing these days due to the fact that these fuels can be afforded without any climate-change aggravation. Biodiesel from different feed stocks has a potential to replace the existing diesel fuel, but the cost involved in the production of biodiesel is more. To mitigate the high production cost, low cost feed stocks of used cooking oils (UCO) can be used. As per the latest statistics approximately 198 MMT/yr of edible oil is used around the world. These UCO are dumped after usage which causes environmental imbalance. In this research an attempt was made to utilize the waste frying palm oil (WFPO) which was available in the college for biodiesel production. To maximize the biodiesel yield latest optimization technique of definitive screening design (DSD) was implemented. It was concluded that maximum yield of 96.23% was achieved at molar ratio of 6:1, reaction temperature of 550C and the catalytic concentration of 1wt%. The fuel samples were tested for different physiochemical properties and fatty acid compositions. It was observed that the properties were within the limits of international standards. Hence, by using the WFPO the overall production cost was reduced and optimization by DSD enhanced the biodiesel yield.Keywords: Waste fried palm biodiesel, optimization, definitive screening design, fatty acid composition, soap
Escolhas contábeis na demonstração dos fluxos de caixa em companhias listadas no novo mercado da B3
Authors: Mendes da Silva Denise , Aversari Martins Vinícius , Guasti Lima Fabiano
Published: April 2019

Este estudo investigou quais fatores podem estar relacionados às escolhas contábeis na DFC realizadas em 112 companhias abertas não financeiras listadas no Novo Mercado da B3 no período de 2010 a 2015. A principal contribuição deste estudo é fornecer um panorama sobre a forma como as empresas consideradas com alto nível de governança corporativa no Brasil estão evidenciando seus fluxos de caixa no que tange à comparabilidade e, também, ao gerenciamento da DFC, fazendo escolhas que impliquem em um aumento do fluxo de caixa operacional. Este estudo oferece evidências de que a maioria das empresas apresenta a DFC pelo método indireto e segue as recomendações de políticas contábeis contidas no CPC 03 para classificar juros e dividendos pagos e recebidos. Além disso, o tamanho da empresa e as oportunidades de crescimento parecem ter relação com as escolhas de classificação de juros pagos e dividendos recebidos, respectivamente. Os resultados no contexto brasileiro diferem de achados anteriores em outros mercados, provavelmente por implicações do ambiente institucional em que as empresas se inserem.
Dividendos, juros sobre capital próprio e níveis de payout: Um estudo investigativo sobre a política de distribuição de dividendos adotada pelas empresas listadas na BM&FBovespa
Authors: Galvão Kécia Da Silveira , Dos Santos Joséte Florencio , De Araújo Jevuks Matheus
Published: April 2019

Este estudo investigou a política de distribuição de dividendos das empresas listadas na Bolsa de Valores de São Paulo entre 2002 e 2013. Assim, procurou identificar se as empresas pagaram (ou não) dividendos; quando distribuíram, se faz por meio de dividendos e/ou Juros sobre Capital Próprio; e, os níveis de payout adotados. Os resultados mostram que a maioria adota o pagamento de 25% do lucro líquido ajustado como dividendos mínimos, possivelmente para garantir participação legal nos lucros das empresas aos administradores. Porém, quando distribuem dividendos, pagam acima deste mínimo, havendo Payout Incremental. Sobre a forma de distribuição, há preferência em adotar apenas os dividendos como forma de remuneração dos investidores ou tê-lo em sua composição. Também foi visto que as companhias evitam mudar a política de distribuição adotada, mantendo a forma de remuneração e o nível de payout.
Divulgações de informações e o efeito no retorno de ações da maior empresa de educação listada na B3 (Brasil, Bolsa, Balcão)
Authors: Gomes Liliane Vicentina , Santos José Odálio dos , Lana Cristiane , Souza Maurício De
Published: April 2019

O mercado é eficiente se novas informações relevantes causarem variação no retorno das ações. As ações podem ser afetadas por eventos e isso pode causar oscilações. A pesquisa analisa a reação do mercado à divulgação de informações sobre a maior instituição de educação listada na B3. Foi utilizado o estudo de eventos para confrontar o comportamento do retorno das ações no período de 30 de setembro 2015 a 30 de setembro de 2017. A pesquisa parte da teoria de mercado eficiente. As informações selecionadas foram distribuídas em grupos, sendo: A -  Divulgação dos resultados trimestrais; B - Operações de compra e venda de participações; C - Mudanças relacionadas ao Financiamento Estudantil. Os resultados evidenciaram que a reação que caracterizou o fator mercado eficiente foi identificada no Grupo C, em parte corroborada pelo comportamento do preço da ação.
Designing Interest and Tax Penalty Regimes
Authors: Waerzeggers Christophe , Hillier Cory , Aw Irving
Published: April 2019

Nearly all tax systems have some form of interest and tax penalty regimes. Interest payable on any late or underpayment of tax seeks to protect the present value of the tax amount to the government budget, whereas penalties are intended to deter taxpayers from defaulting on their tax obligations—and to punish them if they do—to achieve horizontal equity vis-à-vis compliant taxpayers. As interest and penalties serve very different objectives, they should not be applied in a mutually exclusive manner. This Tax Law IMF Technical Note focuses on the key issues that should be taken into consideration in designing interest and penalty regimes in tax legislations.
Spatiotemporal dynamics of fog and low clouds in the Namib unveiled with ground- and space-based observations
Authors: Andersen Hendrik , Cermak Jan , Solodovnik Irina , Lelli Luca , Vogt Roland
Published: April 2019

Abstract. Fog is an essential component of Namib-region ecosystems. Current knowledge
on Namib-region fog patterns and processes is limited by a lack of coherent
observations in space and time. In this study, data from multiple satellite
platforms and station measurements paint a coherent picture of the
spatiotemporal dynamics of fog and low cloud (FLC) distribution. It is found
that observed seasonal FLC patterns derived from satellite observations
differ from fog measurements at coastal station locations, whereas they agree
further inland. This is linked to an observed seasonal cycle in the vertical
structure of FLCs that determines the probability of low-level clouds touching
the ground. For the first time, these observations are complemented by
spatially coherent statistics concerning the diurnal cycle of FLCs using
geostationary satellite data. The average timing of the start of the diurnal
FLC cycle is found to strongly depend on the distance to the coastline
(correlation ≈0.85 north of 25∘ S), a clear indication of
dominant advective processes. In the central Namib, FLCs typically occur 2–4 h
later than in other coastal regions, possibly due to local advection
patterns. The findings lead to a new conceptual model of the spatiotemporal
dynamics of fog and low clouds in the Namib.
Prediction of seismic p-wave velocity using machine learning
Authors: Dumke Ines , Berndt Christian
Published: April 2019

Abstract. Measurements of seismic velocity as a function of depth are generally restricted to borehole locations and are therefore sparse in the world's oceans. Consequently, in the absence of measurements or suitable seismic data, studies requiring knowledge of seismic velocities often obtain these from simple empirical relationships. However, empirically derived velocities may be inaccurate, as they are typically limited to certain geological settings, and other parameters potentially influencing seismic velocities, such as depth to basement, crustal age, or heatflow, are not taken into account. Here, we present a machine learning approach to predict seismic p-wave velocity (vp) as a function of depth (z) for any marine location. Based on a training dataset consisting of vp(z) data from 333 boreholes and 38 geological and spatial predictors obtained from publically available global datasets, a prediction model was created using the Random Forests method. In 60 % of the tested locations, the predicted seismic velocities were superior to those calculated empirically. The results indicate a promising potential for global prediction of vp(z) data, which will allow improving geophysical models in areas lacking first-hand velocity data.
Electrochemical reduction of artemisinin: Chromatographic identification of bulk electrolysis products
Authors: Ombwayo Faraja , Mazzhichette Zahilis , Mugweru Amos
Published: April 2019

Artemisinin is a naturally occurring sesquiterpene lactone with an endo-peroxide bond. This drug is used for treatment of many diseases including malaria. The reduction of this molecule on an electrode surface was carried out by cyclic voltammetry as well as amperometry. Cyclic voltammetry of artemisinin generated one prominent peak wave at -1.0 V and another, smaller one at -0.3 V vs Ag/AgCl reference electrode. The bulk electrolysis of artemisinin on a carbon electrode generated two other irreversible peak waves at around -0.7 and -0.1 V. The concentration of the products was dependent on the time of electrolysis. LC-MS was used to determine the bulk electrolysis products of artemisinin. Initially dihydroartemisinin was generated as the main reduction product. Other reduction products were formed after further reduction of dyhidroartemisinin.
Der Grundversorger zwischen Wettbewerb und Gemeinwohl
Authors: Warg Florian
Published: April 2019

The European markets for electricity and gas are seeing a growing competition, which raises the question of whether the German basic supplier for grid-bound energy is still an institution worth keeping. After careful consideration of arguments from the fields of network economics and competition theory, this remarkable juridical figure seems to be more and more of a contradiction. Findings from behavioural economics and regulatory theory support this judgment further, but in the end, it is constitutional and European law which makes the German implementation of basic supply by way of a supplier of last resort seem obsolete. After all, there has not been a local monopoly of energy supply by law or in real life for quite some time.
The author is an attorney practising in the fields of antitrust and energy law.
Philosophical Considerations: Economical, Epistemological, Cultural and Social Issues
Authors: Valatka Vytis
Published: April 2019

This article analyses and interprets multiple links and interconnections among philosophy, economics, management as well as cognitive, cultural, social, political and educational sciences. Those links and interconnections are investigated in the frames of four methodological paradigms. The first paradigm connects counting, managing and reflecting. The second paradigm is a certain combination of discovering, thinking and solving. The third paradigm binds acting as overcoming, choosing and alternating. Finally, the fourth one relates acts of criticism, creation and construction. This issue is divided into four sections corresponding to the above-mentioned paradigms. This article, in turn, gives concise reviews and interpretations of articles presented in each of the aforementioned sections. Those reviews and interpretations link and bring together different topics of diverse disciplines, such as econometric counting, participation of youth in family business, transformation of classical concept of causality, solving logical paradoxes, trying to overcome various forms of nihilism, seeking alternatives to consumerism, searching for social equality, safety, security and inclusion.
The Transformation of Modern Causality in Heidegger’s Thought
Authors: Stasiulis Nerijus
Published: April 2019

The article presents an analysis of the notion of causality in Heideggerian terms. The modern notion of causality presupposes the Cartesian notion of extended space, the principle of sufficient ground (reason), the notion of object as accessible through mathematical description and the notion of linear time. These notions have been critiqued and transformed in Heidegger’s thought on Being as unconcealing. Hence the new possibility of conceiving causality as unconcealing – which presupposes another, non-algebraic, notion of space, a temporalized principle of ground, another notion of constant presence and, last but not least, the notion of ecstatic time. The article demonstrates that Heidegger’s notion of ecstatic time both implies and presupposes the critique and transformation of the modern notion of causality.
Valoración de los niveles de condición física de escolares de 11-12 años, mediante la aplicación de la Batería ALPHAFITNES
Authors: Martínez Martínez J. , De los Reyes-Corcuera M. , Borrell-Lizana V. , Pastor-Vicedo J. C.
Published: April 2019

El estado de salud en la población escolar muestra un elevado índice de sedentarismo y por ello es necesario conocer el estado de salud de los escolares para así poder realizar una adecuada intervención orientada a la actividad física saludable. El objetivo de este estudio es el conocer los niveles de condición física como referencia para orientarnos en el estado de salud de los escolares de 11 a 12 años a través de la aplicación de la Batería ALPHA-Fitness. La muestra consta de N= 79, (38 niños; 41 niñas). Los resultados muestran cómo los niveles de condición física relacionada con la salud están entre los valores muy bajos y bajos de los establecidos por los referentes de la propia batería.  Resulta necesario un trabajo de intervención basado en la mejora de la Condición Física y más en las niñas que en los niños.
Aproximación al perfil físico y antropométrico en vela ligera, en regatistas de la clase Optimist. Estudio de casos
Authors: Tejada-Medina V. , Ventaja-Cruz J.
Published: April 2019

El propósito de este estudio es determinar el perfil físico del regatista de Optimist, mediante la realización de una serie de pruebas físicas (SJ, flexibilidad y dinamometría manual) y de composición corporal (peso, talla, pliegues y perímetros musculares), describiendo el comportamiento de los indicadores seleccionados y valorando el carácter predictivo de los mismos, para una posible justificación de la existencia de un talento deportivo en Optimist. Se han estudiado a 3 regatistas, que ocupan los tres primeros puestos del ranking provincial de la Ciudad Autónoma de Melilla. Se utilizó un diseño descriptivo correlacional. Los regatistas presentaron los siguientes valores descriptivos de composición corporal: altura (149,6±2,16 cm), peso (35,6±3,67 kg), IMC (15,93±2,04) y %GC (7,86±5,31). En cuanto a las características funcionales, los valores fueron: SJ hcg (22,53±1,68 cm), SJ tv (428,6±16,28 sg), flexibilidad (31,67±1,15) y dinamometría D-I (23,83±2,02; 20,33±1,25). Los resultados no muestran una relación significativa entre las variables de composición corporal y las pruebas físicas realizadas.
Precariedad en la era del trabajo digital
Authors: Muñoz-Rodríguez David , Santos Ortega Antonio
Published: April 2019

Texto introductorio y de presentación del número monográfico.
Cuando la propia vida es el campo laboral
Authors: Gill Rosalind
Published: April 2019

En este artículo reúno los resultados de una serie de estudios sobre el trabajo en los empleos vinculados con las nuevas tecnologías (incluyendo mi propia investigación en el Reino Unido, los Estados Unidos y los Países Bajos), para explorar lo que significa gestionar las vidas en estos nuevos medios. Utilizo aquí la gestión no en su sentido convencional o de escuela de negocios, sino con una inflexión más crítica que proviene del pensamiento marxista, feminista y posestructuralista. Me interesa cómo los propios trabajadores y trabajadoras gestionan vidas, una gestión que se caracteriza por procesos de aceleración, intensificación y contingencia. Usando una óptica foucaultiana, sugiero que trabajar en estos nuevos medios implica múltiples prácticas de autogestión en condiciones de incertidumbre radical.In this article I pull together the findings of a number of studies of new media work (including my own research in the UK, US and Netherlands) to explore what it means to manage lives in new media. I use management here not in its conventional or business school sense but with a more critical inflection that comes from Marxist, feminist and poststructuralist thinking. I am interested in how workers themselves manage lives that are characterised by processes of speeding up, intensification and contingency. Using a Foucauldian optic, I will suggest that working in new media involves multiple practices of managing the self in conditions of radical uncertainty.
Greek Tragedy: a Metaphor of Public Debate and Democratic Participation
Authors: Maldonado Enrique Herreras
Published: April 2019

Athenian citizens deliberate in the assembly, but the theatre also becomes a place for public debate. In addition to being a consequence of economic or cultural aspects, democracy is a consequence of the development of a democratic imaginary. Located in that imaginary, Greek tragedies, regarded as «democratic myths», work to reaffirm Athenian democracy. Far from being dogmatic, the tragic myth explores the contradictions of social and personal life and implicitly or explicitly seeks their correction. This dramatic genre encourages participation from the spectator (citizen) that greatly exceeds the schematic reduction in Aristotelian theory of catharsis. Greek tragedy proposes the existence of an «audience», of spectators who need a sufficient level of maturity to make that assessment. Democracy is a path, or perhaps an active utopia, which should combine the political order with a coherent culture and art.Los ciudadanos atenienses deliberaban en la asamblea, pero también el teatro se convierte en un lugar de debate público. Porque una democracia (también la ateniense) no solo es consecuencia de aspectos económicos o de orden cultural, sino también del desarrollo de un imaginario democrático. Y es en dicho imaginario donde se inscriben las tragedias griegas, consideradas como «mitos democráticos» que servían para reafirmar la democracia ateniense. Lejos de cualquier dogmatismo, el mito trágico explora las contradicciones de la vida social y personal, y se pregunta, de manera expresa o tácita, por su posible corrección. Este género dramático induce a una participación del espectador (ciudadano), que va más allá de la esquemática reducción de la teoría aristotélica de la catarsis. El teatro griego propone la existencia de un «público», de unos espectadores que precisan de una gran madurez para emitir ese juicio. La democracia es un camino, o quizás una utopía activa, que debe conjugar el orden político con una cultura y un arte coherentes.
Determinants of success of donation-based crowdfunding through digital platforms: The influence of offline factors
Authors: Salido-Andres Noelia , Rey-Garcia Marta , Álvarez-González Luis Ignacio , Vázquez-Casielles Rodolfo
Published: April 2019

The purpose of this research consist of exploring the extent to which factors traditionally explaining the success of offline fundraising campaigns for social causes may also influence the success of donationbased crowdfunding (DCF) campaigns promoted by social economy organizations (SEO) through digital platforms. Firstly, factors determining the success of offline fundraising campaigns for social causes are identified from previous literature. Secondly, a set of hypotheses linking these determinants to DCF campaigns is proposed. Thirdly, their explanatory capacity is measured through quantitative analysis based on a database of 360 campaigns fostered by small, medium and large-size organizations via Microdonaciones, a donation-based crowdfunding digital platform, for the period between 2012 and 2017. Logistic regression analysis is used to test the hypotheses proposed. Results confirm the high explanatory capacity of determinants related to the geographical scope of the campaign, the volume of potential beneficiaries involved –in these two cases in unexpected ways-, and the information provided by the promoting organizations. However, factors related to the timing of the campaigns do not influence their success. This research suggests that not only the funding channels and tools but also the nature of the fundraising campaigns themselves have been digitally transformed. Implications of this research may assist SEO in establishing effective relationships with new digital donors in order to achieve sustainable growth.