bluuebunny/crossref_metadata_2025 huggingface dataset:
Investigating EFL Achievement Through the Lens of Demotivation
Authors: Boonchuayrod Piyaporn , Getkham Kanyarat
Published: May 2019

It is generally agreed that demotivation is any forces that reduce a student’s passion or enthusiasm to learn. Despite some studies on demotivation across language levels, culture, and languages; research has not been conducted on university students from different language levels in Thailand. The aim of this mixed-method study is three-fold. Firstly, it attempts to factorize types of demotivation among English major students. Secondly, it examines the effect of demotivation on EFL achievement. Thirdly, it investigates the differences of demotivation in different levels of EFL achievement. The study involved undergraduate students majoring in English completing a questionnaire and being interviewed. The results revealed that there were four potential types of demotivation among English major students: 1) Media, teaching styles and teacher competence; 2) Attitudes towards teachers and classmates; 3) Experiences of failure and attitudes towards English learning, and 4) Characteristics of lessons and class materials. Findings also showed that Demotivation Type 3 (Experiences of failure and attitudes towards English learning) influenced EFL achievement (p <.001). Interestingly, there was a significant difference in the degree of influence of Type 3 among low, moderate, and high levels of EFL achievement. In the conclusion, pedagogical implications of these findings are discussed in order to help teachers understand important factors that demotivate students to achieve in English language learning so that the occurrence of those factors may be avoided.
Substituent Effect on Oxidative Decomposition of Acylferrocenes
Authors: Okada Yutaka , Sakai Motoi
Published: May 2019

Acylferrocenes are oxidized by iron(III) chloride in methanol and then immediately decomposed. In this study, the oxidative decomposition of some alkanoyl- and aroylferrocenes was performed and the substituent effect on the reaction rate was investigated. It was found that the reaction was governed by the accessibility of the oxidizing agent to the iron atom and the degree of electron-withdrawing effect of the carbonyl group towards the ferrocene nucleus.
Introducing and Testing a Measurement Tool for English Language Proficiency: Aisha’s Tool
Authors: Alhussain Aisha M.
Published: May 2019

The IELTS English proficiency tests are discussed as being highly effective in determining students’ level of proficiency in the language. However, the study points out that the processes involved in the administration of the tests along with the associated cost make affect the effectiveness of its use in the assessment of learners. A Sentence Pattern test is offered as an alternative with 97 participants taking part in the assessment to test its effectiveness. Each of the non-native study participants is subjected to both the SP test and the IELTS test for the establishment of the correlation in the results posted for the two tests. The findings demonstrate that the students’ performance in the IELTS test correlated with their corresponding SP test results. High performing students in the IELTS test also posted high scores in their SP test. As demonstrated in the study, the correlation in the results illustrates the effectiveness of the SP test as an alternative for the IELTS tests in proving English language proficiency.
Relationship Between Teacher Job Satisfaction and Productivity in the Asante Akim South District of the Ashanti Region of Ghana
Authors: Senyametor Felix , Minadzi Vincent Mensah , Dankyi Lydia Aframea , Maison Regina Sally
Published: May 2019

The aim of this study was to assess how basic school teachers’ job satisfaction relates to their productivity in the Asante Akim South District of the Ashanti Region of Ghana. The descriptive design was employed in conducting the study. The population covered all the Basic School teachers in the Asante Akim South District. The sample size was 217, made up of 179 males and 38 females. A questionnaire was used to collect data from respondents. Data analysis was done, using frequency and percentage counts as well as the Pearson Product Moment correlation. Key findings of the study indicated that majority (71.9%) of the respondents perceived that the government’s District Best Teacher award scheme only motivates a few teachers at the expense of the majority of teachers. Teachers’ level of job satisfaction shows a strong positive correlation with teacher productivity (r = 0.870, p = 0.020). In order to enhance teacher job satisfaction and productivity, it was recommended that the District Best Teacher award scheme should be made to cover at least 20% of teachers in the district instead of an individual so that majority of them would not feel unmotivated, neglected and unrecognized. Government should make teacher promotions and salaries relatively equitable and competitive with that of workers in other analogous institutions in the country in order to enhance their job satisfaction and productivity.
Second Hankel determinant for a class of analytic functions defined by a linear operator
Authors: Mohammed Aabed , Darus Maslina
Published: May 2019

By making use of the linear operator $\Theta _m^{\lambda ,n} ,\,\,m \in \mathbb{N}=\{1,2,3,\ldots\}$ and $\lambda \,,\,n \in \mathbb{N}_0 = \mathbb{N} \cup \{ 0\}$ given by the authors, a class of analytic functions $S_m^{\lambda ,n}(\alpha ,\sigma ) ( {| \alpha| < \pi/2}, \; 0\leq \sigma <1) $ is introduced. The object of the present paper is to obtain sharp upper bound for functional $ \left| {\,a_2 a_4 - a_3 ^2 } \right|.$
Some properties of weak form of $\gamma$-semi-open sets
Authors: Hussain Sabir , Alghamdi Mohammad Ahmad
Published: May 2019

In this paper, we introduce and explore fundamental properties of weak form of $\gamma$-semi-open sets namely maximal $\gamma$-semi-open sets in topological spaces such as decomposition theorem for maximal $\gamma$-semi-open set. Basic properties of intersection of maximal $\gamma$-semi-open sets are established, such as the $\gamma$-semi-closure law of $\gamma$-semi-radical.
Neighborhood connected perfect domination in graphs
Authors: M.P. Kulandai Vel , P. Selvaraju , C. Sivagnanam
Published: May 2019

Let $G = (V, E)$ be a connected graph. A set $S$ of vertices in $G$ is a perfect dominating set if every vertex $v$ in $V-S$ is adjacent to exactly one vertex in $S$. A perfect dominating set $S$ is said to be a neighborhood connected perfect dominating set (ncpd-set) if the induced subgraph $$ is connected. The minimum cardinality of a ncpd-set of $G$ is called the neighborhood connected perfect domination number of $G$ and is denoted by $\gamma_{ncp}(G)$. In this paper we initiate a study of this parameter.
A perturbation technique to compute initial amplitude and phase for the Krylov-Bogoliubov-Mitropolskii method
Authors: Rahman M. Saifur
Published: May 2019

Recently, a unified Krylov-Bogoliubov-Mitropolskii method has been presented (by Shamsul \cite{1}) for solving an $n$-th, $n=2$ or $n>2$, order nonlinear differential equation. Instead of amplitude(s) and phase(s), a set of variables is used in \cite{1} to obtain a general formula in which the nonlinear differential equations can be solved. By a simple variables transformation the usual form solutions (i.e., in terms of amplitude(s) and phase(s)) have been found. In this paper a perturbation technique is developed to calculate the initial values of the variables used in \cite{1}. By the noted transformation the initial amplitude(s) and phase(s) can be calculated quickly. Usually the conditional equations are nonlinear algebraic or transcendental equations; so that a numerical method is used to solve them. Rink \cite{7} earlier employed an asymptotic method for solving the conditional equations of a second-order differential equation; but his derived results were not so good. The new results agree with their exact values (or numerical results) nicely. The method can be applied whether the eigen-values of the unperturbed equation are purely imaginary, complex conjugate or real. Thus the derived solution is a general one and covers the three cases, i.e., un-damped, under-damped and over-damped.
Generalizations of incomplete elliptic integrals of first and second kinds
Authors: Qureshi M. I. , Quraishi Kaleem A.
Published: May 2019

In this paper, we obtain analytical solutions of incomplete elliptic integrals of first and second kinds. Further, we generalize these incomplete elliptic integrals in the forms of multiple series identities involving bounded multiple sequences.
A oferta de matrículas e cursos de licenciatura presenciais em universidades gaúchas.
Authors: Fonseca Márcia Souza da , Osório Mara Rejane Vieira , Garcia Maria Manuela Alves , Araujo Jair Jonko
Published: May 2019

O artigo descreve e problematiza a oferta de matrículas e cursos de licenciatura em Pedagogia, Letras e Matemática, na modalidade presencial, nas universidades públicas e privadas gaúchas, no contexto da forte pressão oficial pela expansão das universidades brasileiras. Considerando a importância desses cursos no campo das políticas de avaliação e formação docente para a educação básica e das políticas oficiais de expansão do ensino superior desde o final da década de 1990, este estudo justifica-se pela ausência de pesquisas que tenham como foco o impacto dessas políticas no caso do Rio Grande do Sul. Utiliza-se uma metodologia de tipo quantitativa e descritiva a partir de dados dos Censos da Educação Superior (2000, 2007 e 2013). Esses dados são interpretados a partir de estudos que têm como foco o ensino superior e a formação de professores. Com a análise observa-se que houve queda no número total de matrículas, nos cursos estudados, no período 2007-2013. Entretanto, enquanto a queda foi bastante significativa nas universidades privadas, as universidades públicas mantiveram um crescente número de matrículas, devido à criação de novas universidades públicas em regiões do estado desassistidas pela esfera federal e, ainda, à expansão da oferta de cursos e vagas nas universidades públicas já existentes. Constata-se, também, a forte presença das universidades privadas na oferta dos cursos estudados, especialmente na região Metropolitana do estado, em virtude de ser a região de maior desenvolvimento econômico e concentração populacional. Por outro lado, as universidades públicas vão desbravando as regiões mais pobres e remotas do estado.
A produção escrita e a formação de professores
Authors: Nogaro Arnaldo , Porto Ana Paula Teixeira , Porto Luana Teixeira
Published: May 2019

Este artigo trata da escrita como experiência de formação para estudantes e professores. Historicamente a escola assumiu como suas funções ensinar a ler e a escrever, com o passar do tempo privilegiou a leitura em detrimento da escrita, o que faz com que saiamos dela sem experiências mais significativas ou com habilidade de escrever. A investigação que originou este artigo é de natureza teórico-bibliográfica, de cunho qualitativo. A incursão na literatura permitiu encontrar autores para amparar teoricamente a reflexão e a interpretação da temática proposta. A interlocução com obras de estudiosos como Barthes, Marques, Bianchetti, Machado, possibilitou o aprofundamento a respeito do escrever como prática de conhecimento e autoria, bem como alçar questionamentos e construir argumentos em favor da escrita e sua relação com a formação de professores. As descobertas permitem afirmar que a escrita é secundarizada na escola e que os professores, em sua grande maioria, temem-na e não a utilizam como experiência para a sua formação e a formação dos estudantes. A escrita pode ser um recurso poderoso em favor da inclusão e do empoderamento político, no entanto, o estranhamento em relação a ela faz com que se percam oportunidades de crescimento pessoal e de expressão de ideias.
Individualidade em sentido moral e justiça eterna
Authors: Orrutea Filho Rogério Moreira
Published: May 2019

O presente artigo tem como ponto de partida um outro trabalho, de nossa própria autoria, pelo qual buscou-se demonstrar a necessidade de se estabelecer, na filosofia de Schopenhauer, a distinção entre a individualidade em sentido moral e a individuação em sentido corpóreo. Naquele artigo, reconhecemos que nossa abordagem encontrou significativo obstáculo na tese schopenhaueriana da Justiça Eterna. Com o objetivo de remover este obstáculo, tentaremos agora demonstrar que a Justiça Eterna é, em última instância, incompatível com elementos mais fundamentais da filosofia de Schopenhauer.
A teleologia da vontade em Schopenhauer
Authors: Silva Helio Lopes da
Published: May 2019

Neste artigo pretendo explorar os argumentos que Schopenhauer avança em favor de sua suposta concepção de uma Vontade não-teleológica, e pretendo também contrastar tal concepção a uma concepção "tradicional" de vontade como essencialmente teleológica, ou como uma capacidade de atuar de forma direcionada a fins ou finalidades. Ao final, vou sugerir que, embora a concepção schopenhaueriana de vontade não seja a tradicional, não é fácil entendê-la como estabelecendo a Vontade como completamente não-teleológica.
Vidas tomando corpo
Authors: Sattler Janyne
Published: May 2019

Este ensaio discorre sobre os conceitos de ‘corpo’ ou ‘corporeidade’ e ‘criaturidade’, inspirados na abordagem conceitual e metodologicamente wittgensteiniana do filósofo australiano Raimond Gaita e suas aproximações com a literatura de J.M. Coetzee, para pensar em uma proposta que se quer como metaética, almejando, no entanto, uma alternativa às “éticas animais” hodiernas ao estabelecer como condição básica para a moralidade – estruturada sobre o campo do significado – do corpo vivo. Trata-se de salientar o viés político do corpo e da linguagem, ao perscrutar os significados de nossas relações com a critauridade humana e não humana em vista de um mundo mais vivível para nós e para eles.
Considerações sobre o corpo em Mikhail Bakhtin
Authors: Teixeira Marilia Dalva
Published: May 2019

Este trabalho tem por objetivo expor como o corpo é apresentado na obra do filósofo russo Mikhail Bakhtin, em especial nos textos O autor e a personagem na atividade estética e Cultura popular na Idade Média e no Renascimento: O contexto de François Rabelais. Nesses textos, Bakhtin apresenta o corpo como objeto ideologicamente saturado, quando submetido a movimentos axiológicos da relação entre sujeitos. Esse corpo, possuidor de valor axiológico, depende do outro para se estabelecer esteticamente e pode, na atividade estética, tornar-se manifestação de duas consciências não coincidentes, bem como se apresentar como uma visão de mundo historicamente situada.
Editorial
Authors: Debona Vilmar
Published: May 2019

O trabalho não apresenta resumo.
Posições e disposições de um corpo: o erótico e o pornográfico na ótica feminina: práticas de submissão ou de resistência nos dispositivos de poder
Authors: Amitrano Georgia Cristina
Published: May 2019

O presente artigo/ensaio é um olhar outro para o foco da lente filosófica que não abarca, ainda, a questão do amor, do corpo e do corpo feminino como possibilidade real do filosofar. A análise visa entender como os corpos femininos foram pensados e como ainda o são no universo falocêntrico e em certas correntes feministas. E isso é realizado a partir da estética e da política erótica e pornográfica, pensadas como possibilidades de resistência diante da negação do Ser da mulher. Erótica e pornografia são entendidas aqui como conceitos que também não se ajustam ao foco filosófico do que se chama ‘boa filosofia’.
Primary pancreatic ductal adenocarcinoma cell cultures represent the features of native tumours
Authors: Ger Marija , Žalytė Eglė , Kaupinis Algirdas , Kurlinkus Benediktas , Petrulionis Marius , Šileikis Audrius , Strupas Kęstutis , Valius Mindaugas
Published: May 2019

Pancreatic ductal adenocarcinoma (PDAC) is one of the deadliest forms of cancer due to the lack of diagnostic tools at the early stage and low efficiency of current chemotherapeutic approaches. The anticancer compounds with proven efficiency in established cell cultures often fail validation in further research. In this study, we employed PDAC patient-derived primary cell cultures to evaluate the efficiency of chemotherapeutic agents. Alongside, patients’ tissue samples were analysed by high-throughput differential proteomic analysis. We have shown that main firstline chemotherapeutic agents gemcitabine and FOLFIRINOX have little to no effect on the viability of patient-derived primary PDAC cells. The comparative proteomic and bioinformatic analysis of PDAC tumours shows an increase in the components of the extracellular matrix and focal adhesions and also overexpression of the downstream signaling from a variety of receptors, most notably PDGF receptor β and ErbB1 receptor. Consistently, all tumour-derived cell cultures assayed express a high level of PDGF receptor β. The enhancement of multiple signaling pathways leads to the increase in cell survival, proliferation, and resistance to apoptosis. Here we demonstrated the promising value of patient-derived primary PDAC cultures as a model for anticancer drug research and evaluation for individualized therapy.
Geografiniai žemėnaudos kaitos tyrimai Lietuvoje: raida, kryptys, perspektyvos
Authors: Veteikis Darijus , Piškinaitė Eglė
Published: May 2019

Straipsnyje analizuojami per 1954–2018 m. atlikti žemės naudmenų / žemės dangos kaitos geografiniai (apimantys teritorinį aspektą) tyrimai Lietuvoje. Atliekant analizę buvo sistemingai gilintasi į Lietuvos ir užsienio autorių publikacijas, Vilniaus universiteto (VU) studentų baigiamuosius darbus. Išryškėjo skirtingos analizuojamos temos darbų tyrimo dimensijos ir laikotarpiai, reprezentuojami daugelio įvairių specialistų – geografų, žemėtvarkininkų, žemės ūkio specialistų. Atlikus VU studentų baigiamųjų darbų analizę, parengta darbų, nagrinėjančių žemėnaudos kaitą, aprėpties kartoschema. Paaiškėjo, kad atliekamų žemėnaudos kaitos tyrimų kiekis yra susijęs su politiniais, socialiniais, ekonominiais pokyčiais šalyje, kurie lemia ir akivaizdžius žemėnaudos pokyčius, ir kintantį publikacijų nagrinėjama tematika skaičių. Daugiausia tyrimų yra aprašomojo pobūdžio ir apima sąlyginai neilgus 10–20 metų laikotarpius. Studentų baigiamieji darbai dažniausiai orientuoti į lokalinius žemės naudmenų struktūros kaitos tyrimus. Atsižvelgiant į Europos žemėnaudos kaitos tyrimų tendencijas, siūlytina į Lietuvos geografinius žemės naudmenų tyrimus įtraukti mažai ištirtus kraštovaizdžių tipus ir vietoves, identifikuoti svarbiausius kraštovaizdžio kaitos veiksnius, tobulinti kiekybinės kraštovaizdžio kaitos analizės metodus, vykdyti tyrimus, apimančius ilgesnius istorinius laikotarpius ir tarpvalstybinius regionus, ieškoti bei atsižvelgti į subtilius ir naujus kraštovaizdžio procesus, tyrinėti stabilias, mažai besikeičiančias žemėnaudos struktūras, padėsiančias nustatyti veiksnius, atsparius išorės poveikiui.
Vegetação ripária e métodos de estudo
Authors: Anschau Sandra Aparecida , Neres Júlio Cesar Ibiapina , Carvalho Aluísio Vasconcelos , Guimarães Ana Paula Martins , Neres Liberta Lamarta Garcia Favoritto , Cerqueira Fernando Barnabé
Published: May 2019

Esta revisão bibliográfica compara alguns termos utilizados para se referir à vegetação marginal que ocorre ao longo de cursos de água, concluindo que o termo “ripário” é o mais adequado, pois significa “próximo ao curso de água”, tratando de conceitos de distância e água. A vegetação ripária tem várias funções de proteção, dentre elas, a proteção dos solos ribeirinhos contra a erosão. É considerada de grande importância, pois retém impurezas, preservando a integridade das águas. Deve-se ainda somar a esta função da floresta ripária a hidrológica, representada por processos importantes para a estabilidade da microbacia, para a manutenção da quantidade e qualidade da água e para a manutenção do ecossistema aquático. Uma das características das vegetações ripárias é a heterogeneidade ambiental que se repete dentro de diferentes domínios vegetacionais, e acabam por definir diferentes métodos para o estudo das vegetações ripárias, estudos estes como o da fenologia de plantas, fundamental em qualquer plano vegetacional; o estudo fitossociológico, que possibilita a avaliação da estrutura e composição da vegetação; o florístico, estudo inicial para o conhecimento da flora; o dendrométrico, que trata da medição de árvores, tanto do ponto de vista individual quanto do coletivo; e o dendrológico, que tem como base conhecer as espécies a partir de regiões específicas, dando condições para o conhecimento da constituição arbórea de uma determinada comunidade vegetacional. Portanto, este trabalho teve por finalidade, realizar uma revisão bibliográfica apresentando as principais definições de “vegetação ripária”, suas funções e métodos de estudo para conservação.
La logística como fuente de valor añadido al eCommerce
Authors: Budet Jofra Xavier , Pérez Gómez Alexis
Published: May 2019

Las plataformas de eCommerce se convierten en actores cada vez más relevantes de la economía global, modificando los hábitos de compra y consumo, y provocando un impacto decisivo en el mercado de la distribución, fabricación y prestación de servicios logísticos. La consolidación y mejora del eCommerce se basa en garantizar la excelencia en la experiencia de usuario, desde el proceso de compra hasta la entrega final del producto o del servicio solicitado. En este sentido, la logística es un factor clave. La penetración de Amazon en los hogares ha sacudido fuertemente el escenario competitivo. Ha obligado a los grandes distribuidores (y fabricantes) a dar una respuesta que satisfaga las nuevas expectativas de servicio de los compradores, iniciando una exigente carrera para dominar la cadena de valor y la experiencia del cliente. Con el presente artículo, los autores analizan el panorama actual, las repercusiones en la cadena de suministro y las tendencias que presentan las plataformas de eCommerce, identificando áreas de oportunidad generadas por las expectativas de clientes cada vez más exigentes.
Las personas y la cadena de suministro
Authors: Gómez-Cedeño Milena , Guitart i Tarrés Laura , Morantes Guerra Shantall , Li Zeng Yohana
Published: May 2019

La gestión de los recursos humanos (HRM) con un enfoque hacia la cadena de suministro (SC) permite a las empresas gestionar eficazmente sus cadenas de suministros. Este artículo demuestra la importancia del estudio de los recursos humanos en la cadena de suministro (HRSC) realizando un análisis en profundidad de las investigaciones en estos dos campos (HR y SC) que permite identificar sus potencialidades y sus carencias. En este sentido, se han identificado las áreas temáticas abordadas en la literatura y sus principales contribuciones, así como la existencia de lagunas en la literatura. A partir del análisis efectuado, se han localizado 53 publicaciones que destacan el potencial de la HRSC. Los resultados muestran que en los últimos cuatro años, entre 2012 y 2017, se ha dado un incremento significativo del 49 % de las investigaciones sobre HRSC.
Rīgas Politehnikuma / Rīgas Politehniskā institūta studenti un absolventi – Latvijas Republikas pasludināšanas akta dalībnieki
Authors: Zigmunde Alīda , Baldiņš Alvars
Published: May 2019

2018. gadā atzīmē Latvijas Republikas (LR) dibināšanas simtgadi. Pirms simts gadiem, 1918. gada 18. novembrī, Latvijas valsts dibināšanas aktā piedalījās 38 Latvijas Tautas padomes (turpmāk – Tautas padome) locekļi. Neviens no viņiem nepieredzēja Latvijas Republikas atjaunošanu, un vairumam no viņiem mūžs aprāvās pirms Otrā pasaules kara beigām. Latvijas Republikas dibināšanas akta dalībnieku vidū bija septiņi Rīgas Politehnikuma (RP) / Rīgas Politehniskā institūta (RPI) absolventi un viens augstskolas diplomu neieguvis students. No septiņiem absolventiem četri 1941. gadā piedzīvoja represijas un tika aizvesti uz Sibīriju, divi pēc Otrā pasaules kara devās trimdā, viens bija miris spēka gados 1924. gadā. Daļa no Latvijas Republikas proklamēšanas akta dalībniekiem atstājuši rakstītas liecības par valsts tapšanas pirmsākumiem. Visi Tautas padomes locekļi bija cienījami Latvijas pavalstnieki, daļa no viņiem par nopelniem Tēvijas labā apbalvoti ar Triju Zvaigžņu ordeni.
Standardized representation of the LIDC annotations using DICOM
Authors: Fedorov Andrey , Hancock Matthew , Clunie David , Brochhausen Mathias , Bona Jonathan , Kirby Justin , Freymann John , Pieper Steve , Aerts Hugo , Kikinis Ron , Prior Fred
Published: May 2019

The Lung Imaging Data Consortium and Image Database Resource Initiative (LIDC) conducted a multi-site reader study that produced a comprehensive database of Computed Tomography (CT) scans for over 1000 subjects annotated by multiple expert readers. The result is hosted in the LIDC-IDRI collection of The Cancer Imaging Archive (TCIA). Annotations that accompany the images of the collection are stored using project-specific XML representation. This complicates their reuse, since no general-purpose tools are available to visualize or query those objects, and makes harmonization with other similar type of data non-trivial. To make the LIDC dataset more FAIR (Findable, Accessible, Interoperable, Reusable) to the research community, we prepared their standardized representation using the Digital Imaging and Communications in Medicine (DICOM) standard. This manuscript is intended to serve as a companion to the dataset to facilitate its reuse.
Super black eyespots of the Eyed elater
Authors: Wong Victoria L , Marek Paul E
Published: May 2019

Scattering of light by surface structures leading to near complete structural absorption creates an appearance of “super black.” Well known in the natural world from bird feathers and butterfly scales, super black has evolved independently from various anatomical structures. Due to an exceptional ability to harness and scatter light, these biological materials have garnered interest from optical industries. Here we describe the false eyespots of the Eyed elater click beetle, which attains near complete absorption of light by an array of vertically-aligned microtubules. These cone-shaped microtubules are modified hairs (setae) that are localized to eyespots on the dorsum of the beetle, and absorb 96.1% of incident light (at a 24.8° collection angle) in the spectrum between 300 – 700 nm.
Production of Activated Carbon from Agroindustrial Residues and Application in the Treatment of Desalinator Reject
Authors: Lima S. S. A. , Paiva S. C. de , Figueiredo H. T. , Takaki G. M. C. , Messias A. S.
Published: May 2019

Residues of agroindustrial origin can be used for various purposes, including the production of activated carbon. In order to conduct the experiment, residual biomass of Cocos nucifera-C and grape marc-B were used at the doses corresponding to 100C/0B, 75C/25B, 50C/50B, 25C/75B and 0C/100B. The appropriate operating ranges for the production of activated carbon were identified and an experiment was carried out with a full factorial design, type 32, with three replicates and a control.  The activated carbon produced was in contact with the desalinator reject for 30, 60, 120 and 180 minutes, after which the extracts were physico-chemically analyzed. The data were submitted to statistical analysis, using Statistic software, with a percentage reduction in the characteristics evaluated: pH (13.2), electrical conductivity (1), sodium (4.7), potassium (35.6), calcium (3.2), magnesium (zero) and chloride (18.2), indicating the mixture of coconut fiber and grape marc in 50C/50B ratio as being the most promising in the adsorption of the chemical elements of the reject, when in contact for up to an hour.
Correlation and Path Coefficient Analysis for Morphological and Biochemical Traits in Diverse Pomegranate (Punica granatum L.) Genotypes
Authors: Perveen Nusrat , S. Cholin Sarvamangala , Hipparagi Kulapati , Prabhuling G. , Murthy B. N. S. , Peerjade Dadapeer
Published: May 2019

The present experiment was conducted to study the correlation and path coefficient analyses among some morphological and biochemical traits of twenty-three pomegranate genotypes. Results of correlation analysis showed a high, positive and statistically significant (at 0.1% P) correlation between fruit weight and fruit length (r= 0.897), peel weight (r=0.931), fruit volume (r= 0.67), fruit diameter (r=0.554) and total number of arils per fruit (r=0.428). Peel weight exerted direct positive effect as well indirect positive effect on fruit weight through characters like fruit volume, fruit length, total no. of arils per fruit, aril weight and fruit diameter while among the biochemical traits, fruit juiciness exerted maximum positive direct effect on TSS (0.298). The results suggested that these traits could be used for indirect selection of genotypes for higher yield and fruit quality traits will be suitable for cultivation as well as for use in breeding programme.
Mathematical Model of Cholera Transmission with Education Campaign and Treatment Through Quarantine
Authors: Nyaberi H. O. , Malonza D. M.
Published: May 2019

Cholera, a water-borne disease characterized by intense watery diarrhea, affects people in the regions with poor hygiene and untreated drinking water. This disease remains a menace to public health globally and it indicates inequity and lack of community development. In this research, SIQR-B mathematical model based on a system of ordinary differential equations is formulated to study the dynamics of cholera transmission with health education campaign and treatmentthrough quarantine as controls against epidemic in Kenya. The effective basic reproduction number is computed using the next generation matrix method. The equilibrium points of the model are determined and their stability is analysed. Results of stability analysis show that the disease free equilibrium is both locally and globally asymptotically stable R0 < 1 while the endemic equilibrium is both locally and globally asymptotically stable R0 > 1. Numerical simulation carried out using MATLAB software shows that when health education campaign is efficient, the number of cholera infected individuals decreases faster, implying that health education campaign is vital in controlling the spread of cholera disease.
MONITORING DAN ANALISIS JADWAL PROYEK MENGGUNAKAN METODE PERFORMANCE INTENSITY DAN CPM PADA PROYEK HOTEL
Authors: Setiadi Ivan Pratama , Andi Andi
Published: May 2019

Ada sebuah metode penjadwalan baru yang dikembangkan tahun 2007 oleh Murray B. Woolf, yaitu Performance Intensity. Metode ini mempunyai dua variabel utama yaitu duration days dan time consumption. Penelitian ini bertujuan untuk melakukan monitoring dan analisa dengan menggunakan metode Performance Intensity dan CPM dengan dan mengetahui perbandingan analisa tanggal akhir sebuah proyek menggunakan metode Performance Intensity dengan metode penjadwalan CPM yang lebih dulu digunakan. Penelitian ini mempunyai batasan yaitu pekerjaan struktur, dinding dan tangga. Untuk melakukan penelitian ini diperlukan jadwal rencana sebagai acuan. Selain itu diperlukan data start date, finish date, persentase selesai tiap aktivitas yang didapat dari hasil monitoring setiap hari dan dilakukan analisa perbandingan mingguan dengan jadwal rencana.           Jadwal rencana awal proyek selama 189 hari. Penelitian dilakukan selama 10 minggu dimulai dari tanggal 15 September 2014. Hasil dari penelitian adalah terdapat perbedaan analisa tanggal akhir antara metode Performance Intensity dengan metode CPM. Analisa tanggal akhir Performance Intensity mempunyai range antara 123-185 hari, sedangkan analisa metode CPM mempunyai range 175-199 hari. Perbedaaan range analisa prediksi tanggal berakhirnya proyek disebabkan metode Performance Intensity menggunakan laju pekerjaan kumulatif rata-rata sebagai tolak ukurnya yang selalu berubah-ubah tiap periode.
PEMODELAN PENJADWALAN LINIER DENGAN ALOKASI SUMBER DAYA MANUSIA PADA PROYEK PERUMAHAN
Authors: TAN HEDWIG ANGDIARTO , Alifen Ratna
Published: May 2019

Metode penjadwalan linier cocok untuk proyek dengan aktivitas sederhana, dan repetitif dengan jumlah unit yang tipikal, seperti proyek jalan, irigasi, tunnel, apartment, dan perumahan sederhana. Pada penelitian ini dilakukan pemodelan penjadwalan linier proyek pembangunan perumahan sebanyak 50 unit tipikal. Simulasi alokasi sumber daya manusia dan penggunaan buffer agar penggunaan sumber daya manusia dapat seefisien mungkin.

Hasil penelitian diperoleh bahwa simulasi ke-8 dengan menggunakan buffer memiliki durasi 314 hari dengan 18 kelompok kerja, apabila dibandingkan dengan simulasi ke-9 tanpa menggunakan buffer memiliki durasi 180 hari dan idle time 134 hari inefisiensi 1522 orang hari.

 

Linear scheduling method is suitable for projects with repetitive activities, as well as tipical mass product units such as a road, apartment, and residential housings. In this research linear schedule modeling was carried out on residential typical housings project of 50 units. The simulation of linear scheduling is to minimize the idle times by using time buffers and human resources allocation so that the usage of human resources can be as efficient as possible.

The research findings show that the 8th simulation by using buffers has a project duration of 314 days were chosen with 18 working groups, compares to 9th simulation without buffers that has a duration of 180 days and 134 days of idle time which with 1522 man day of inefficient.
An Integrated Microfluidics Approach for Personalized Cancer Drug Sensitivity and Resistance Assay
Authors: Desyatnik Inna , Krasner Matan , Frolov Ludmila , Ronen Maria , Guy Ortal , Wasserman Danit , Tzur Amit , Avrahami Dorit , Barbiro‐Michaely Efrat , Gerber Doron
Published: May 2019

Cancer is the second leading cause of death globally. Matching proper treatment and dosage is crucial for a positive outcome. Any given drug may affect patients with similar tumors differently. Personalized medicine aims to address this issue. Unfortunately, most cancer samples cannot be expanded in culture, limiting conventional cell‐based testing. Herein, presented is a microfluidic device that combines a drug microarray with cell microscopy. The device can perform 512 experiments to test chemosensitivity and resistance to a drug array. MCF7 and 293T cells are cultured inside the device and their chemosensitivity and resistance to docetaxel, applied at various concentrations, are determined. Cell mortality is determined as a function of drug concentration and exposure time. It is found that both cell types form cluster morphology within the device, not evident in conventional tissue culture under similar conditions. Cells inside the clusters are less sensitive to drugs than dispersed cells. These findings support a heterogenous response of cancer cells to drugs. Then demonstrated is the principle of drug microarrays by testing cell response to four different drugs at four different concentrations. This approach may enable the personalization of treatment to the particular tumor and patient and may eventually improve final patient outcome.
Soft Electronic Skin for Multi‐Site Damage Detection and Localization
Authors: Markvicka Eric J. , Tutika Ravi , Bartlett Michael D. , Majidi Carmel
Published: May 2019

Soft‐matter technologies have a potentially central role in wearable computing, human–machine interaction, soft robotics, and other emerging applications that require highly compliant and elastic materials. However, these technologies are largely composed of soft materials that are susceptible to damage and loss of functionality when exposed to real‐world loading conditions. To address this critical challenge, we present a soft responsive material that, like natural nervous tissue, is able to identify, compute, and signal damage in real‐time. The soft composite material contains liquid metal droplets dispersed in an elastomer matrix that rupture when mechanical damage occurs (e.g., compression, fracture, or puncture), creating electrically conductive pathways. The resulting change in local conductivity can be actively sensed and coupled with actuation, communication, and computation in a manner that presents new opportunities to identify damage, calculate severity, and respond to prevent failure within soft material systems. When placed on the surface of a soft, humanoid‐like inflatable structure, the skin can detect puncture damage and control the operation of an embedded fan to prevent deflation.
High‐Performance CO2 Capture through Polymer‐Based Ultrathin Membranes
Authors: Ji Yufan , Zhang Mengchen , Guan Kecheng , Zhao Jing , Liu Gongping , Jin Wanqin
Published: May 2019

Thin film composite (TFC) membranes have attracted great research interest for a wide range of separation processes owing to their potential to achieve excellent permeance. However, it still remains challenging to fully exploit the superiority of thin selective layers when mitigating the pore intrusion phenomenon. Herein, a facile and generic interface‐decoration‐layer strategy collaborating with molecular‐scale organic–inorganic hybridization in the selective layer to obtain a high‐performance ultrathin film composite (UTFC) membrane for CO2 capture is reported. The interface‐decoration layer of copper hydroxide nanofibers (CHNs) enables the formation of an ultrathin selective layer (≈100 nm), achieving a 2.5‐fold increase in gas permeance. The organic part in the molecular‐scale hybrid material contributes to facilitating CO2‐selective adsorption while the inorganic part assists in maintaining robust membrane structure, thus remarkably improving the selectivity toward CO2. As a result, the as‐prepared membrane shows a high CO2 permeance of 2860 GPU, superior to state‐of‐the‐art polymer membranes, with a CO2/N2 selectivity of 28.2. The synergistic strategy proposed here can be extended to a wide range of polymers, holding great potential to produce high‐efficiency ultrathin membranes for molecular separation.
High Performance Anion Exchange Membrane Fuel Cells Enabled by Fluoropoly(olefin) Membranes
Authors: Zhu Liang , Peng Xiong , Shang Shun‐Li , Kwasny Michael T. , Zimudzi Tawanda J. , Yu Xuedi , Saikia Nayan , Pan Jing , Liu Zi‐Kui , Tew Gregory N. , Mustain William E. , Yandrasits Michael , Hickner Michael A.
Published: May 2019

Although the peak power density of anion exchange membrane fuel cells (AEMFCs) has been raised from ≈0.1 to ≈1.4 W cm−2 over the last decade, a majority of AEMFCs reported in the literature have not been demonstrated to achieve consistently high performance and steady‐state operation. Poly(olefin)‐based AEMs with fluorine substitution on the aromatic comonomer show considerably higher dimensional stability compared to samples that do not contain fluorine. More importantly, fluorinated poly(olefin)‐based AEMs exhibit high hydroxide conductivity without excessive hydration due to a new proposed mechanism where the fluorinated dipolar monomer facilitates increased hydroxide dissociation and transport. Using this new generation of AEMs, a stable, high‐performance AEMFC is operated for 120 h. When the fuel cell configuration is subjected to a constant current density of 600 mA cm−2 under H2/O2 flow, the cell voltage declines only 11% (from 0.75 to 0.67 V) for the first 20 h during break‐in and the cell voltage loss is low (0.2 mV h−1) over the subsequent 100 h of cell testing. The ease of synthesis, potential for low‐cost commercialization, and remarkable ex situ properties and in situ performance of fluoropoly(olefin)‐based AEM renders this material a benchmark membrane for practical AEMFC applications.
Unraveling the Origin and Mechanism of Nanofilament Formation in Polycrystalline SrTiO3 Resistive Switching Memories
Authors: Kwon Deok‐Hwang , Lee Shinbuhm , Kang Chan Soon , Choi Yong Seok , Kang Sung Jin , Cho Hae Lim , Sohn Woonbae , Jo Janghyun , Lee Seung‐Yong , Oh Kyu Hwan , Noh Tae Won , De Souza Roger A. , Martin Manfred , Kim Miyoung
Published: May 2019

Three central themes in the study of the phenomenon of resistive switching are the nature of the conducting phase, why it forms, and how it forms. In this study, the answers to all three questions are provided by performing switching experiments in situ in a transmission electron microscope on thin films of the model system polycrystalline SrTiO3. On the basis of high‐resolution transmission electron microscopy, electron‐energy‐loss spectroscopy and in situ current–voltage measurements, the conducting phase is identified to be SrTi11O20. This phase is only observed at specific grain boundaries, and a Ruddlesden–Popper phase, Sr3Ti2O7, is typically observed adjacent to the conducting phase. These results allow not only the proposal that filament formation in this system has a thermodynamic origin—it is driven by electrochemical polarization and the local oxygen activity in the film decreasing below a critical value—but also the deduction of a phase diagram for strongly reduced SrTiO3. Furthermore, why many conducting filaments are nucleated at one electrode but only one filament wins the race to the opposite electrode is also explained. The work thus provides detailed insights into the origin and mechanisms of filament generation and rupture.
Rising Up: Hierarchical Metal–Organic Frameworks in Experiments and Simulations
Authors: Luo Yi , Ahmad Momin , Schug Alexander , Tsotsalas Manuel
Published: May 2019

Controlled synthesis across several length scales, ranging from discrete molecular building blocks to size‐ and morphology‐controlled nanoparticles to 2D sheets and thin films and finally to 3D architectures, is an advanced and highly active research field within both the metal–organic framework (MOF) domain and the overall material science community. Along with synthetic progress, theoretical simulations of MOF structures and properties have shown tremendous progress in both accuracy and system size. Further advancements in the field of hierarchically structured MOF materials will allow the optimization of their performance; however, this optimization requires a deep understanding of the different synthesis and processing techniques and an enhanced implementation of material modeling. Such modeling approaches will allow us to select and synthesize the highest‐performing structures in a targeted rational manner. Here, recent progress in the synthesis of hierarchically structured MOFs and multiscale modeling and associated simulation techniques is presented, along with a brief overview of the challenges and future perspectives associated with a simulation‐based approach toward the development of advanced hierarchically structured MOF materials.
Silver‐Nanowire Mesh‐Structured Transparent Conductive Film with Improved Transparent Conductive Properties and Mechanical Performance
Authors: Hu Shaowei , Gu Jiahui , Zhao Weiwei , Ji Hongjun , Ma Xing , Wei Jun , Li Mingyu
Published: May 2019

Silver nanowires (AgNWs) are an optimum material for fabricating flexible transparent conductive films (TCFs), which are the primary materials in flexible optoelectronic devices. In most studies, TCFs are produced by coating AgNW onto a substrate to form a random network. However, according to some reports, a mesh‐structured network may allow superior performance. The effects of a mesh structure are quantitatively studied, a simple calculation method to derive property curves of mesh‐structured networks from those of random networks is presented, and a rule to fabricate mesh‐structured TCFs with improved performance is determined. Different networks are then fabricated using a template method and transferred onto a polyethylene terephthalate substrate to produce flexible TCFs. Through a series of experiments, it is verified that the mesh structure makes a positive contribution to both the transparent conductive properties and the flexibility. The transmittance of the film is 95.2% when the sheet resistance is 36.0 Ω sq−1, and the properties of the film are well maintained after 5000 bending cycles at a bending curvature of 5 mm.
Active Separation Control on Thick Wind Turbine Airfoils by Means of Steady and Unsteady Blowing
Authors: Kankatala Prabhu , Bangga Galih
Published: May 2019

Investigations of active flow control (AFC) using steady and unsteady sinusoidal blowing jet on thick wind turbine airfoils are performed. The focus is on improving the performance of the DU 00‐W2‐401 airfoil through parametric study and to discuss the effectiveness of optimized configuration. The unsteady Reynolds‐Averaged Navier‐Stokes (URANS) and delayed‐detached eddy simulation (DDES) approaches are employed with controlled flow conditions. The turbulent statistics produced from the flow development through DDES approach is used to analyze the flow. Unsteadiness associated with the massively separated flows is investigated and a strategy is charted to perform the parametric study efficiently and profitably. The interdependencies of the blowing jet parameters are investigated. The studies address airfoil performance improvement through the nonzero‐net‐mass‐flux (NZNMF) slot blowing at different positions, angles of blowing, flow rates, forcing frequencies, and amplitudes of the blowing jet. The computed time‐averaged aerodynamic force coefficients, pressure distributions, and time‐resolved flow field contours are utilized to analyze the flow conditions at various configurations. A final optimum parametric configuration is found out, which results in improved aerodynamic performance. The optimum configuration is tested for airfoil sections of a 10 MW generic turbine at actual operating inflow conditions and ascertained that it is effective.
Driving Cells with Light‐Controlled Topographies
Authors: Puliafito Alberto , Ricciardi Serena , Pirani Federica , Čermochová Viktorie , Boarino Luca , De Leo Natascia , Primo Luca , Descrovi Emiliano
Published: May 2019

Cell–substrate interactions can modulate cellular behaviors in a variety of biological contexts, including development and disease. Light‐responsive materials have been recently proposed to engineer active substrates with programmable topographies directing cell adhesion, migration, and differentiation. However, current approaches are affected by either fabrication complexity, limitations in the extent of mechanical stimuli, lack of full spatio‐temporal control, or ease of use. Here, a platform exploiting light to plastically deform micropatterned polymeric substrates is presented. Topographic changes with remarkable relief depths in the micron range are induced in parallel, by illuminating the sample at once, without using raster scanners. In few tens of seconds, complex topographies are instructed on demand, with arbitrary spatial distributions over a wide range of spatial and temporal scales. Proof‐of‐concept data on breast cancer cells and normal kidney epithelial cells are presented. Both cell types adhere and proliferate on substrates without appreciable cell damage upon light‐induced substrate deformations. User‐provided mechanical stimulation aligns and guides cancer cells along the local deformation direction and constrains epithelial colony growth by biasing cell division orientation. This approach is easy to implement on general‐purpose optical microscopy systems and suitable for use in cell biology in a wide variety of applications.