bluuebunny/crossref_metadata_2025 huggingface dataset:
A temática ambiental e o processo educativo: significados elaborados por licenciandos de física, química, ciências biológicas e matemática
Authors: Lopes Mona Lisa Ferreira Prado , Silva Luciano Fernandes , Santos Janaina Roberta dos
Published: May 2019

Neste artigo são apresentadas reflexões sobre os significados que alunos dos cursos de licenciatura em Física, Química, Matemática e Ciências Biológicas de uma universidade pública do estado de Minas Gerais elaboram sobre a temática ambiental e suas articulações com o processo educativo. Estas reflexões estão apoiadas em um estudo empírico desenvolvido a partir de questionários e entrevistas semi-estruturadas. Participaram deste estudo 21 alunos que haviam concluído, naquela oportunidade, mais de 60% das disciplinas dos seus referidos cursos. Este estudo recebeu ainda suporte dos procedimentos analíticos da Análise de Conteúdo. Considera-se que os estudantes destes cursos, de modo geral, reconhecem problemas ambientais a partir de uma perspectiva mais pragmática, entendendo que estes podem ser administrados exclusivamente a partir de conhecimentos sistematizados, construídos a partir de conceitos de seus campos disciplinares. Neste contexto, eles não desenvolveram articulações mais evidentes entre problemas ambientais e questões de natureza política, social e/ou econômicas.
Construção de significados na interlocução entre contextualização e atividades experimentais no ensino de química
Authors: Santos Giseli Pereira dos , Latini Rose Mary
Published: May 2019

Neste estudo temos por objetivo analisar como vem sendo estabelecido o vínculo entre a contextualização e as atividades experimentais no ensino de Química na Educação Básica, visando contribuir para as práticas de ensino de Química. Tomamos como recorte artigos publicados na Revista Química Nova na Escola (QNESc), a partir de 2006, ano de publicação das Orientações Curriculares Nacionais do Ensino Médio. Para análise dos dados utilizamos a Análise Textual Discursiva (ATD) que apontou diferentes entendimentos da comunidade de ensino de Química sobre a articulação entre contextualização e experimentação.
Noções de estudantes a respeito dos aspectos da natureza da ciência e de uma investigação científica
Authors: Brenzam Filho Francisco , Bologna Soares de Andrade Mariana Aparecida
Published: May 2019

Esta pesquisa teve por objetivo investigar as concepções de estudantes do Ensino Fundamental sobre seus hábitos alimentares e alimentação equilibrada. Este estudo qualitativo e caracterizado como pesquisa exploratória incluiu 15 alunos do oitavo ano do Ensino Fundamental de uma escola estadual da região noroeste do estado do Rio Grande do Sul, Brasil. Os dados foram coletados mediante questionário e discutidos com base em uma análise de conteúdo. Os resultados revelaram que os alunos compreendem ao menos em parte a importância de uma alimentação balanceada para a saúde. Além disso, os participantes contribuíram com concepções variadas sobre alimentação balanceada, algumas das quais apresentaram uma relação com os conhecimentos científicos associados, ao passo que outras eram embasadas principalmente em conceitos espontâneos. Contudo, algumas concepções sobre o tema careceram de robustez, o que aponta para a necessidade de aprofundar a discussão sobre alimentação equilibrada na escola.
Concepções sobre radioatividade envolvendo a perspectiva ambiental de licenciandos de química
Authors: Da Silva Roberta Maria , Aquino Kátia Aparecida da Silva , Da Silva Suely Alves
Published: May 2019

Indo além dos acidentes e cálculos presentes no Ensino de Radioatividade, propomos um novo olhar ao resgatar a condição da radioatividade como fenômeno natural e presente nas nossas vidas mais do que possamos imaginar. Tal noção foi objeto de uma proposta formativa num curso de Licenciatura em Química numa instituição pública de Pernambuco na forma de pesquisa-ação como estratégia. Tivemos como objetivo analisar as concepções dos licenciandos através do uso de mapas conceituais acerca da Radioatividade antes, ao final e três meses após o término da proposta formativa sobre a temática Radioatividade Ambiental. De modo geral, notamos que houve uma gradual evolução especialmente quanto às correções dos equívocos identificados, bem como a consolidação de algumas informações alusivas à perspectiva ambiental. Por meio desses resultados, acreditamos estar contribuindo para o desenvolvimento de novas práticas de ensino com base nos conceitos de radioatividade para futuros professores de química.
Experimental tests of phytoplankton response to ornithological eutrophication in Arctic freshwaters
Authors: Mariash Heather L. , Rauito Milla , Mallory Mark , Smith Paul A.
Published: May 2019

Abstract. Many populations of Arctic-breeding geese have increased in abundance in recent decades, and in the Canadian Arctic, Snow (Chen caerulescens) and Ross’ Geese (Chen rossii) are formally considered overabundant by wildlife managers. The impacts of these overabundant geese on terrestrial habitats are well documented, and more recently, studies have suggested impacts to freshwater ecosystems as well. The direct contribution of nutrients from goose faeces to water chemistry could have cascading effects on biological functioning, through changes in phytoplankton productivity and community composition. We demonstrated previously that goose faeces can enrich ponds with nutrients at a landscape scale. Here, we show experimentally that goose droppings rapidly released nitrogen and phosphorus when submerged in freshwater, increasing the dissolved nitrogen and phosphorus in the water. This resulted in both a decrease in the nitrogen:phosphorus ratio and an increase in cyanobacteria in the goose dropping treatment. In contrast, this pattern was not found when we submerged cut sedge (Carex sp.) leaves. These results demonstrate that geese act as biovectors, causing terrestrial nutrients to be bioavailable in freshwater systems. Collectively, the results demonstrate the direct ecological consequences of ornithological nutrient loading from hyperabundant geese in Arctic freshwater ecosystems.
Spatial gradients in soil-carbon character of a coastal forested floodplain are associated with abiotic features, but not microbial communities
Authors: Sengupta Aditi , Indivero Julia , Gunn Cailene , Tfaily Malak M. , Chu Rosalie K. , Toyoda Jason , Bailey Vanessa L. , Ward Nicholas D. , Stegen James C.
Published: May 2019

Abstract. Coastal terrestrial-aquatic interfaces (TAIs) are dynamic zones of biogeochemical cycling influenced by salinity gradients. However, there is significant heterogeneity in salinity influences on TAI soil biogeochemical function. This heterogeneity is perhaps related to unrecognized mechanisms associated with carbon (C) chemistry and microbial communities. To investigate this potential, we evaluated hypotheses associated with salinity-associated shifts in organic C thermodynamics, biochemical transformations, and heteroatom content in a first-order coastal watershed in the Olympic Peninsula of Washington state, USA. In contrast to our hypotheses, thermodynamic favorability of water soluble organic compounds in shallow soils decreased with increasing salinity, as did the number of inferred biochemical transformations and total heteroatom content. These patterns indicate lower microbial activity at higher salinity that is potentially constrained by accumulation of less favorable organic C. Furthermore, organic compounds appeared to be primarily marine/algal-derived in forested floodplain soils with more lipid-like and protein-like compounds, relative to upland soils that had more lignin-, tannin-, and carbohydrate-like compounds. Based on a recent simulation-based study, we further hypothesized a relationship between microbial community assembly processes and C chemistry. Null modelling revealed strong influences of dispersal limitation over microbial composition, which may be due to limited hydrologic connectivity within the clay-rich soils. Dispersal limitation indicated stochastically assembled communities, which was further reflected in the lack of an association between community assembly processes and C chemistry. This suggests a disconnect between microbial community composition and C biogeochemistry, thereby indicating that the salinity-associated gradient in C chemistry was driven by a combination of spatially-structured inputs and salinity-associated metabolic responses of microbial communities that were independent of community composition. We propose that impacts of salinity on coastal soil biogeochemistry need to be understood in the context of C chemistry, hydrologic/depositional dynamics, and microbial physiology, while microbial composition may have less influence.
Weakening anomalies of East Asian Summer Precipitation Influenced by the Tibetan Plateau Warming Amplification
Authors: Liang Mei , Xu Jianjun , Wu Liguang , Xu Xiangde
Published: May 2019

Abstract. The present study documents the on East Asian precipitation in summer influenced by elevation-dependent temperature change over the Tibetan Plateau (TP). The temperature of the TP and its surrounding areas decreases with altitude by 0.43–0.45 °C/100 meters, which is lower than the 0.6 °C/−100 meters in the troposphere. The magnitude of the trend of temperature increase with elevation and the amplification of warming over the TP comprise an important feature of the temperature change. TP warming is consistently the important contributor to the variation of East Asian precipitation in summer from 1979 to 2016, but their relationship weakens as the warming over the TP amplifies. The southern flood–northern drought pattern is weak compared with when the TP warming trend has been removed. Warming amplification of the TP may weaken the atmospheric circulation anomaly pattern. The rate of anticyclonic circulation strengthening has slowed in the upper and lower levels over Mongolia in East Asia, which leads to the northern drought feature weaken. Meanwhile striking cyclonic circulation anomalies are reduced in the southeastern part of China, the northern part of the South China Sea, and the northwestern Pacific. The atmospheric response to TP warming might be related to two distinct Rossby wave trains. After TP warming amplifying, one in the extratropics that moves along the upper-level westerly jetstream and the other in the tropics that moves along the low-level monsoon westerly have weakened. The downdrafts prevailed in the Northern Asia receded, which is conducive to precipitation in the area. Updrafts prevailed in the Southeast Asia is deteriorating, which is not advantageous to precipitation.
Organization of Dust Storms and Synoptic Scale Transport of Dust by Kelvin Waves
Authors: Pokharel Ashok Kumar , Kaplan Michael L.
Published: May 2019

Abstract. Based on the large scale transport of dust driven by the winds parallel to the mountains in the Harmattan, Saudi Arabian, and Bodélé Depression dust storms cases, a detailed study of the generation of Kelvin Waves and its possible role in organizing these dust storms and large scale dust transport was accomplished. For this study, observational and numerical model analyses were done in an in depth manner. For this, MERRA reanalysis datasets, WRF simulated high resolution variables, MODIS/Aqua and Terra images, EUMETSAT images, NAAPS aerosol modelling plots, and MERRA-2 dust scattering AOD modelling plots, surface observations, and rawinsonde soundings were analyzed for each of these three case studies. We found there were meso-β scale (horizontal length scale of 20–200 km) adjustment processes resulting in Kelvin waves only in the Harmattan and the Bodélé Depression cases. The Kelvin wave preceded a cold pool accompanying the air behind the large scale cold front instrumental in the major dust storm. We find that this Kelvin wave organized the major dust storm in a narrow zone parallel to the mountains before it expanded upscale (meso-α to synoptic).
Global distribution of nearshore slopes with implications for coastal
retreat
Authors: Athanasiou Panagiotis , van Dongeren Ap , Giardino Alessio , Vousdoukas Michalis , Gaytan-Aguilar Sandra , Ranasinghe Roshanka
Published: May 2019

Abstract. Nearshore slope, defined as the cross-shore gradient of the subaqueous profile, is an important input parameter which affects hydrodynamic and morphological coastal processes. It is used in both local and large-scale coastal investigations. However, due to unavailability of data, most studies, especially those that focus on continental or global scales, have historically adopted a uniform nearshore slope. This simplifying assumption could however have far reaching implications for predictions/projections thus obtained. Here, we present the first global dataset of nearshore slopes with a resolution of 1 km at almost 620,000 points along the global coastline. To this end, coastal profiles were constructed using global topo-bathymetric datasets. The results show that the nearshore slopes vary substantially around the world. An assessment of sea level rise (SLR) driven coastline recession (for an arbitrary 0.5 m SLR) with a globally uniform coastal slope of 1:100, as done in previous studies, and with the spatially variable coastal slopes computed herein shows that, on average, the former approach would under-estimate coastline recession by about 40 %, albeit with significant spatial variation. The final dataset has been made publicly available at https://doi.org/10.4121/uuid:a8297dcd-c34e-4e6d-bf66-9fb8913d983d.
Regional circulation patterns of Mediterranean Outflow Water near the Iberian and African continental slopes
Authors: de Pascual-Collar Álvaro , G. Sotillo Marcos , Levier Bruno , Aznar Roland , Lorente Pablo , Amo-Baladrón Arancha , Álvarez-Fanjul Enrique
Published: May 2019

Abstract. The Mediterranean Outflow Water (MOW) is a dense water
mass originated in the Strait of Gibraltar. Downstream of the Gulf of Cádiz,
the MOW forms a reservoir region west of the Iberian continental slopes at a
buoyant depth of approximately 1000 m. This region plays a key role as the
main centre where the MOW is mixed and distributed into the North Atlantic.
The seafloor in this area is characterized by the presence of a complex
bathymetry with three abyssal plains separated by mountain chains. Although
the topographic features do not reach the surface, they influence ocean
flows at intermediate and deep ocean layers, conditioning the distribution
and circulation of MOW. The Copernicus Marine Environmental Monitoring Service (CMEMS) Iberian–Biscay–Ireland (IBI) ocean reanalysis is used to provide a detailed view of the
circulation and mixing processes of MOW near the Iberian and African
continental slopes. This work emphasizes the relevance of the complex
bathymetric features defining the circulation processes of MOW in this
region. The high resolution of the IBI reanalysis allows us to make a
description of the mesoscale features forced by the topography. The
temperature, salinity, velocity, transport, and vorticity fields are
analysed to understand the circulation patterns of MOW. The high-resolution
circulation patterns reveal that Horseshoe Basin and the continental
slope near Cape Ghir (a.k.a. Cap Rhir or Cabo de Aguer) are key areas controlling the mixing processes of MOW
with the surrounding water masses, mainly North Atlantic Central Water (NACW)
and Antarctic Intermediate Water (AAIW). The water mass
variability is also analysed by means of composite analysis. Results
indicate the existence of a variability in the MOW tongue which retracts and
expands westwards in opposition to the movement of the underlying North
Atlantic Deep Water.
A Multi-phasic Approach for Estimating the Biot Coefficient for Grimsel Granite
Authors: Selvadurai Patrick , Selvadurai Paul , Nejati Morteza
Published: May 2019

Abstract. This paper presents an alternative approach for estimating the Biot coefficient for the Grimsel granite, which appeals to the multi-phasic mineralogical composition of the rock. The modelling considers the transversely isotropic nature of the rock that is evident from both the visual appearance of the rock and determined from mechanical testing. Conventionally, estimation of the compressibility of the solid material is performed by fluid saturation of the pore space and pressurization. The drawback of this approach in terms of complicated experimentation and influences of the unsaturated pore space is alleviated by adopting the methods for estimating the solid material compressibility using developments in theories for multiphasic elastic composite materials. The results of the proposed approach are used to develop a set of bounds for the Biot coefficient.
Ancillary services from wind turbines: AGC from a single Type 4 turbine
Authors: Rebello Eldrich , Watson David , Rodgers Marianne
Published: May 2019

Abstract. Wind turbines possess the technical ability to provide various ancillary services to the electrical grid. Several regions have set ambitious targets of providing an increasing share of annual electrical energy from wind and other renewable sources of generation. Despite this, renewable generators such as wind and solar have traditionally not been allowed to provide significant amounts of ancillary services, in part due to the variable and uncertain nature of their electricity generation. Increasing levels of renewable generation, however, continue to displace existing synchronous generation and thus necessitate new sources of ancillary or system services. This work is part of an ongoing project that seeks to provide empirical evidence of how ancillary services can be provided from wind turbines. We focus specifically on providing secondary frequency response (AGC) and demonstrate that wind turbines have the technical capability to provide this service. The algorithms used are intentionally simple so as to evaluate the capabilities and limitations of the turbine technology. This work presents results from a single, 800 kW, IEC Type 4 wind turbine. 10 % of rated power is offered on the regulation market. We do not separate up- and down-regulation into individual services. Up-regulation is offered through a 5 % constant power curtailment. The AGC update interval is 4 s, to mimic real-world conditions. We use performance scoring methods from the Pennsylvania-Jersey-Maryland (PJM) operator and the National Research Council (NRC) of Canada to quantify the wind turbine's response. We use the calculated performance scores, annual site wind data and 2017 PJM market price data to estimate income from providing secondary frequency regulation. In all cases presented, income from the regulation market is greater than the energy income lost due to curtailment.
The Impact of Corporate Governance Mechanisms on the Relationship Between Cash Holdings and Audit Fees in Egyptian Listed Companies
Authors: Abdel-Wanis Eman
Published: May 2019

This paper explores the impact of corporate governance mechanisms on the nature of the relationship between cash holdings and audit fees, which helps provide an opportunity to identify whether these mechanisms enable to mitigate agency problems, and thus lower audit fees through a sample of 78 Egyptian listed firms in EGX 100 during the period 2014-2016 using panel data analysis. Results indicated that cash holding increases auditing fees. The board characteristics affect negatively on the relationship between cash holdings and audit fees. Also, ownership structure affects negatively on the relationship between cash holdings and audit fees. As well audit committee affects negatively on the relationship between cash holdings and audit fees. There results support the view that corporate governance mitigate on the relationship between cash holdings and audit fees.
An Analysis of the Relationship Between Work-Life Balance and Productivity in Ghana
Authors: Ghareeb Ahmed Eid Mohamed
Published: May 2019

The study examines the relationship between work-life balance and Productivity among Employee in Medium Organizations in Ghana. The study adopts a quantitative research method. The data of 240 Employee respondents were analyzed using different statistical techniques such as reliability survey, descriptive of variable analysis, correlation analysis using the Statistical Package for Social Science (SPSS). The correlation results indicated that work-life balance is positively correlated with Productivity. also, for effective Productivity to be enhanced, the level of motivation needs to be improved.
Vocabulary Fluency and Writing Skill: A Case Study on Kurdish Students in Learning English Vocabulary
Authors: Muhammed Areen Ahmed
Published: May 2019

Currently, a wide range of papers have been conducted in the field of L2 learners’ vocabulary problems and difficulty in academic written texts; commonly, L1 processing routine over L2 learning brought problems in maintaining vocabulary fluency in academic writing for non-native speakers of English. The establishment of an initial form-meaning link should be regarded as early steps of vocabulary learning. The study investigates major problems of Kurdish learners of English Language in homogenous classes regarding the fluency use of vocabulary in their writings. Besides all those studies which have been carried out in the specified field; however, still, less progress can be seen, and still, students face obstacles when it comes to vocabulary fluency in English taught program.The study was conducted on Kurdish university students (n=33). English department of Charmo University was selected as the setting for the study. Moreover, 30 students who participated in the questionnaire were equally divided on both genders. Later, few students, in the range of 3, were tested from the same department. Though tests were considered as the main criteria for finding out students’ major problems in writing and especially vocabulary fluency, whenever the students were put in the position of the test, outer factors will take the bigger slice and main piece of the puzzle. Several essay writings were collected from them and different problems were carried out through those feedbacks that were given by the assigned program.As it can be seen in the discussion section personal desires and interest on the aforementioned language is not to the degree that they can improve their abilities; besides, each of culture, society, and family awareness plays a crucial part in common sense. Moreover, Sociology and psychology of the student, as each of culture, religion, gender differences, male dominance, and family motivation, have vital roles and effects on their use of low efficiency and contextually low frequent vocabulary when they compose in English.
Corporate Social Responsibility (CSR) Practices in Coffee Producer Farmers’ Cooperative Unions: The Case of Bench-Maji, Kaffa, and Sheka Zones, South Western Ethiopia
Authors: Begajo Tesfaye Megiso , Bilina Yidenek Woldesenbet , Getie Gubay Aniley
Published: May 2019

The seventh ICA principle of "concern for community" clearly urges the cooperatives to carry out sustainable community development activities. Even though the cooperatives are serving the community directly or indirectly, their sight to the concept Corporate Social Responsibility (CSR) is not clearly considered by their members, academicians, and the government. The objective of this study was to assess the corporate social responsibility practices performed by Coffee Producer Farmers’ Cooperative Unions at the study area. In this study primary and secondary data source were used. The size of respondents was 395 members of Cooperative Society and 50 Government officials. The data was analyzed using SPSS version 20. The finding shows that there are job creation, supply of agricultural input, and expansion of coffee processing industry for serving both members and non-members, whereas  drawback on the awareness creation to the community, participation of community in planning, implementing, and evaluating community projects, inconsistent allocation of community fund, and financial statements at unions’ offices for CSR budget. Therefore, management of the unions should participate the community during planning, implementing, and evaluating socially responsible projects, cooperative social responsibility practices should be thoroughly supervised and supported by the government, cooperatives from their annual surplus should allocate community fund, both GOs and NGOs working on sustainable development activity at the area must work with cooperatives, and Cooperatives have to maintain separate book of account to record financial activities of cooperative social responsibility practices.
Cash Flow Restatements: Stock Market Reaction to Overstated versus Understated Restatements
Authors: Alfonso Elio , Hollie Dana , Yu Shaokun Carol
Published: May 2019

The Securities and Exchange Commission has become increasingly concerned with the rising number of restatements to statements of cash flows (SCFs). Regulators and practitioners are generally more focused on the overstatement of operating cash flows, while the understatement of operating cash flows is often overlooked but may have the same (or more) negative economic consequences. We examine market reactions to cash flow restatements (CFRs) where firms overstate or understate cash flows from 2000 to 2013. This study finds that 41% of firms overstated operating cash flows, while a surprising 48% understated operating cash flows. While we find that the market does not react to overstated operating cash flows or overstated total cash flows (TCFs), we find a negative response to understated operating cash flows and understated TCFs. Interestingly, the market penalizes these firms more for understating rather than overstating cash flows. There is a CFR disclosure post-announcement drift in abnormal returns that occurs for both understated operating and understated TCFs. We provide evidence that the often-overlooked understated CFRs may have “real” economic consequences and that they should be evaluated further and given the same consideration as overstatements by auditors, regulators, and investors.
Performance Analysis of an Innovative ORC-based Micro-scale CCHP System under Lebanese Conditions
Authors: JRADİ Muhyiddine , RİFFAT Saffa
Published: May 2019

Considering the high demand for cooling, heating and
electricity and with more than 300 annual sunny days, an innovative hybrid
biomass-solar driven micro-scale tri-generation system is proposed to provide
cooling, heating and electricity under Lebanese conditions. The system
comprises an organic Rankine cycle-based combined heat and power unit, a liquid
desiccant dehumidification unit and a dew point evaporative cooling unit. A
complete technical, economic and environmental assessment of the tri-generation
system is performed to assess its applicability and feasibility. Employing a 2
kWe ORC-based CHP unit, the useful heat output ranges between 4.2 and 11.75 kW,
with an electric power capacity between 0.7 and 1.92 kW. The maximum hourly
cooling capacity delivered by the coupled cooling and dehumidification system
is attained in August with 8.7 kW. The tri-generation system allows annual
savings of 8225 USD on the heating bill, 960 USD on the electricity bill and 950
USD on the cooling bill compared to conventional production technologies. In
addition, the CO2 emissions reduction ranges between 3.1 tons in June
and 9.2 tons in March. The results of this study demonstrate the large
potential of using such tri-generation systems under the Lebanese conditions
compared to the conventional separate energy production technologies.
A Systematic Study of Cubic Equations of State with van der Waals Mixing Rules and Different Combining Rules in Predicting the Densities of LNG and Natural Gas Model Systems
Authors: AL-MANTHARİ Monther , AL-WADHAHİ Majid , NASRİFAR Khashayar , VAKİLİ-NEZHAAD G. Reza
Published: May 2019

Cubic
equations (EoSs) of state are successfully used in petroleum and natural gas
industry. In order to extend these equations to mixtures, van der Waals mixing
rules with Lorentz-Berthelot (LB) combining rules are often employed; however,
the accuracies of these EoSs in predicting the densities of hydrocarbon mixtures
are not adequate. The main objective of this study was comparing 13 EoSs
coupled with 10 combining rules in predicting the densities of hydrocarbon mixtures.
Binary and ternary liquid mixtures, LNG mixtures and synthetic natural gas
mixtures comprising 752 data points were collected and used in this study.
Results revealed that for predicting the liquid densities of binary and ternary
mixtures, the Schmidt and Wenzel (SW) EoS coupled with Hudson-McCoubrey (HMC)
or LB combining rules are the best among the others. The SW EoS coupled with
the LB combining rules were also the best in predicting the densities of the LNG
mixtures. Additionally, the LB combining rules are the best in predicting
natural gas mixtures densities using the Patel and Teja (PT), SW and
Patel-Teja-Valderrama (PTV) EoSs. In general, it was found that the Redlich-Kwong
(RK) family EoSs, SW and Trebble-Bishnoi-Salim (TBS) EoSs are best coupled with
the LB combining rules. However, the Peng and Robinson (PR) family EoSs with Halgren
(HHG) combining rules were in better agreement with experimental data. The Waldman-Hagler
(WH) combining rules lacked predictability when coupled with the most EoSs.
Universal covers of topological modules and a monodromy principle
Authors: Mucuk Osman , Ozdemir Mehmet
Published: May 2019

Let $R$ be a simply connected topological ring and $M$ be a topological left $R$-module in which the underling topology is path connected and has a universal cover. In this paper, we prove that a simply connected cover of $M$ admits the structure of a topological left $R$-module, and prove a Monodromy Principle, that a local morphism on $M$ of topological left $R$-modules extends to a morphism of topological left $R$-modules.
Characterization of a class of graphs with unique minimum graphoidal cover
Authors: Arumugam S. , Rajasingh Indra , Pushpam P. Roushini Leely
Published: May 2019

A graphoidal cover of a graph $ G$ is a collection $ \psi$ of (not necessarily open) paths in $ G$ such that every vertex of $ G$ is an internal vertex of at most one path in $ \psi$ and every edge of $ G$ is in exactly one path in $ \psi$. The minimum cardinality of a graphoidal cover of $ G$ is called the graphoidal covering number of $ G$ and is denoted by $ \eta$ . Two graphoidal covers $ \psi_1$ and $ \psi_2$ of a graph $ G$ are said to be isomorphic if there exists an automorphism $ f$ of $ G$ such that $ \psi_2=\{f(P)/P\in \psi_1\}$. A graph $ G$ is said to have a unique minimum graphoidal cover if any two minimum graphoidal covers of $ G$ are isomorphic. In this paper we characterize the class of all graphs $ G$ with a unique minimum graphoidal cover when $ \delta=2$ and no end block of $ G$ is a cycle.
A double inequality for remainder of power series of tangent function
Authors: Chen Chao-Ping , Qi Feng
Published: May 2019

By mathematical induction, an identity and a double inequality for remainder of power series of tangent function are established.
On errors of a unified family of approximation forms of bivariate continuous functions
Authors: Kao Chung-Siung
Published: May 2019

Approximation forms for a regular bivariate functions $f(x,y)$ were obtained by putting expectation on a convergent bivariate stochastic sequence for which some proper error bounds are herein derived to evaluate the applicability of the approximation forms when actually applied to be approximates of regular bivariate functions.
A summability type factor theorem
Authors: Rhoades B. E. , Savas Ekrem
Published: May 2019

We obtain sufficient conditions for the series $ \sum\nolimits a_{n} \epsilon_{n}$ to be absolutely summable of order $ k$ by a wieghted mean method.
Riquier problem in a biharmonic space
Authors: Damlakhi Moustafa K.
Published: May 2019

After defining the notion of a biharmonic space $ O$ which generalizes $ {\Bbb R}^n$, Riemann surfaces and Rimannian manifolds, we discuss the Riquier problem for an open set in $ O$ provided with the Wiener boundary.
Necessary and sufficient conditions for oscillation of second order neutral difference equations
Authors: Thandapani E. , Mahalingam K.
Published: May 2019

Consider the second order difference equation of the form$\Delta^2(y\n-py_{n-1-k})+q_nf(y_{n-\ell})=0,\quad n=1,2,3,\ldots  \hskip 1.9cm\hbox{(E)}$where $ \{q_n\}$ is a nonnegative real sequence, $ f:{\Bbb R}\rightarrow {\Bbb R}$ is continuous such that $ uf(u)>0$ for $ u\not= 0$, $ 0\le p
Some new inverse type Hilbert-Pachpatte inequalities
Authors: Lu Zhongxue
Published: May 2019

In this paper, some new inverse type Hilbert-Pachpatte inequalities are given.
Interpolations of Jensen's inequality
Authors: Dragomir S. S. , Pearce C. E. M. , Pevcari’ c J.
Published: May 2019

Weighted and unweighted interpolations of general order are given for Jensen's integral inequality. Various upper-bound estimates are made for the differences between the interpolates and some convergence results erived. The results generalise and subsume a body of earlier work and employ streamlined proofs.
Actions of finite groups on commutative rings I
Authors: Naoum A. G. , Al-Aubaidy W. K.
Published: May 2019

Let $R$ be a commutative ring with 1, and let $G$ be a finite group of automorphisms of $R$. Denote by $R^G$ the fixed subring of $G$, and let $I$ be a subset of $R^G$. In this paper we prove that if the ideal generated by $I$ in $R$ satisfies a certain property with regard to projectivity, flatness, multiplication or related concepts, then the ideal generated by $I$ in $R^G$ also satisfies the same property.
Improvements of Ostrowski and generalised trapezoid inequality in terms of the upper and lower bounds of the first derivative
Authors: Dragomir S. S.
Published: May 2019

In this paper improvements of the Ostrowski and generalised Trapezoid inequalities are found in terms of the upper and lower bounds of the first derivative.
On the degree of approximation of functions belonging to a Lipschitz class by Hausdorff means of its Fourier series
Authors: Rhoades B. E.
Published: May 2019

In a recent paper Lal and Yadav [1] obtained a theorem on the degree of approximation for a function belonging to a Lipschitz class using a triangular matrix transform of the Fourier series representation of the function. The matrix involved was the product of $ (C, 1) $, the Cesaro matrix of order one, with $ (E, 1) $, the Euler matrix of order one. In this paper we extend this result to a much wider class of Hausdorff matrices.
Inequalities and monotonicity of the ratio for the geometric means of a positive arithmetic sequence with arbitrary difference
Authors: Guo Bai-Ni , Qi Feng
Published: May 2019

For all nonnegative integers $ k $ and natural numbers $ n $ and $ m $, we have$$ \frac{a(n+k+1)+b}{a(n+m+k+1)+b} < \frac{[\prod_{i=k+1}^{n+k} (ai+b)]^{\frac{1}{n}} }{ [\prod_{i=k+1}^{n+m+k} (ai+b)]^{\frac{1}{n+m}}} \le \sqrt{\frac{a(n+k)+b}{a(n+m+k)+b} } , $$where $ a $ and $ b $ are positive constants. The equality above is valid for $ n = 1 $ and $ m = 1 $. Moreover, some monotonicity results for the sequences involving $ \sqrt[n]{\prod_{i=k+1}^{n+k} (ai+b)} $ are obtained.
Anti-integral extensions $ {R[{\alpha}]/R$
Authors: Baba Kiyoshi , Yoshida Ken-Ichi
Published: May 2019

Let $ R $ be an integral domain and $ \alpha $ an anti-integral element of degree $ d $ over $ R $. In the paper [3] we give a condition for $ \alpha^2-a$ to be a unit of $ R[\alpha] $. In this paper we will generalize the result to an arbitrary positive integer $n$ and give a condition, in terms of the ideal $ I_{[\alpha]}^{n}D(\sqrt[n]{a}) $ of $ R $, for $ \alpha^{n}-a$ to be a unit of $ R[\alpha] $.
Fractional integration of certain special functions
Authors: Chaurasia V. B. L. , Singhal Vijay Kumar
Published: May 2019

We derive an Eulerian integral and a main theorem based upon the fractional integral operator associated with generalized polynomials given by Srivastava [8. 185, Eq.~(7)] and $H$-function of several complex variables given by Srivastava and Panda [11, p.271, Eq.~(4.1)] which provide unification and extension of numerous results in the theory of fractional calculus of special functions in one and more variables. Certain interesting sepcial cases (known and new) have also been discussed.
Further results on differential inequality of a class of second order neutral type
Authors: Wang Peiguang , Wu Yonghong
Published: May 2019

In this paper, we develop several new results related to the nonexistence criteria for eventually positive solutions of a class of second order neutral differential inequalities with distributed deviating arguments. The work generalizes various existing result.
Boundary values of analytic functions without distributional point values
Authors: Estrada Ricardo
Published: May 2019

We give a method to construct distributions that are boundary values of analytic functions which have non-tangential limits at points where the distributional point value does not exist.
A note on Ostrowski and Gr"uss type discrete inequalities
Authors: Pachpatte B. G.
Published: May 2019

The aim of the present note is to establish some new discrete inequalities of the Ostrowski and Gr"uss type involving two functions and their forward differences.
Cello in the Baroque, part 2: Cello literature in the 17th century
Authors: Kościukiewicz Jakub
Published: May 2019

The present text is the second instalment of the cycle of articles based on its author’s doctoral dissertation entitled The birth of cello as a solo instrument – instruments, prac-tice, and selected literature examples (Academy of Music in Łódź, 2017). It is an at-tempt to systematise the knowledge about the first cello literature creators and their compositions. The text includes descriptions (characterisations) of the first pieces writ-ten for the cello as early as in the 17th century along with short biographical sketches of their composers. The article characterises the main centres of development of cello mu-sic, such as Bologna and Modena, the places of work of Giovanni Battista Vitali, Do-menico Gabrielli, Petronio Franceschini, Giuseppe Jacchini, Bononcini brothers, Gio-vanni Battista Degli Antoni, Domenico Galii, Giuseppe Colombi, and others. These composers mainly focused around Bologna’s Accademia Filarmonica and Basilica of San Petronio, as well as the court of Francesco II d'Este in Modena. The article also pays attention to the circumstances in which the first attempts to write cello pieces were made. Moreover, it mentions singular historical items of early cello literature written in such centres as Rome, Venice or Naples, where Carlo Fedeli, Giovanni Lorenzo Lulier, Nicola Francesco Haym or other composers worked.
Scriabin – piano music in the context of the composer’s creative ideology. Part 2
Authors: Piechnat Mateusz
Published: May 2019

The article is the second part of the text devoted to the profile and piano works of Alexander Scriabin. The composer had an extraordinary piano talent and the ability of coloured hearing. He worked out an innovative musical language based on a unique harmonic style. He was an unprecedented visionary of art, he had knowledge on philosophical topics, he was also a mystic who wanted to save the mankind thanks to his creative output. Throughout the period of around 20 years, Scriabin’s musical language transformed drastically, which is most fully shown in his piano pieces, especially miniatures and sonatas.
The second part of the article presents a general characterisation of Scriabin’s piano compositions and musical language in subsequent stages of his creative work. The analysis refers to style and form-related topics, melodics and harmony he used, texture and timbre phenomena and the connections between piano and symphonic pieces. The author of the article reflects on the essence of Scriabin’s artistic orientation and the fact whether the change of his musical language can be called an “evolution” as such. An important element of the article is the presentation of the structure of each piano sonata. The included characterisation of the change of his musical language is an addition to the first part of the cycle, enabling the reference to the stages of the composer’s life juxtaposed there with the description of the transformation of his artistic views.
Cello in the Baroque, part 1
Authors: Kościukiewicz Jakub
Published: May 2019

The article was based on a fragment of the author’s doctoral dissertation entitled The birth of cello as a solo instrument – instruments, practice, and selected literature examples (Academy of Music in Łódź, chapter The evolution of cello in the 17th century) and consists of two parts. The first part outlines of the evolution of cello from its birth in the 16th century to the 18th century (the text is supplemented with illustrations), whereas the second part describes the role and use of cello in music of that period. The introduction to the article includes a critical reference to the list of academic and popular science publications therein, in Polish and other languages, touching on the cello issue in the 17th and 18th centuries. The historical part touches on the circumstances of how the violin family emerged with a special attention paid to bass representatives of that group of instruments. Following a detailed analysis of preserved instruments, their reliable copies, luthier publications, illustrations and treatises from that period, the author discussed the construction of the earlies cellos. Apart from data concerning sizes and scale length of these instruments, the article includes information about their body, neck, fingerboard (with slope angle), bridge and tailpiece, materials they were made of, and types and gauge of strings used at that time. It also describes cello tuning methods. Moreover, the author mentions different types of cello (piccolo, da spalla, basse de violon) and different ways of how it was held. A separate issue are the bows, especially types of bows, their evolution and ways of holding. This part of the article is concluded with a list of different names of bass variants of the violin used in the 16th and 17th centuries before the name cello/violoncello finally settled. The second part of the article elaborates on the most important functions of cello: as a consort instrument, a universal continuo instrument or a solo instrument. Cello (along with viola da gamba or dulcian/bassoon) managed especially well as a melodic instrument co-rendering the continuo parts, and the result was that the basso continuo became the most important domain of cello in the Baroque, having a significant influence on the shape of playing technique and performance practice of that instrument. As one of melodic bass instruments, cello performed an important role in shaping the concertante style, along with the violin, shawm/oboe, cornet or flute. It was that practice combined with the improvisation practice developed simultaneously (which also influenced the development of the instrument itself) that the idea to write first autonomous compositions for the cello (solo, chamber or with basso continuo) emerged from at the end of the 17th century. Continuation of this article, which shall be devoted to Baroque works for the cello and their composers, will be published in the following issue of “Notes Muzyczny”.
Harpsichord or piano? Different concepts in the 18th century keyboard music
Authors: Pilch Marek
Published: May 2019

The article touches on the problem musicians come across while referring to compositions without a specified instrument they were meant for. This problem is particularly noticeable in the harpsichord music from the end of the 18th century when there were numerous keyboard instruments. Some of them, so to say, were at the end of their career (harpsichord, clavichord), others only at the beginning (piano). The author of the article is primarily interested in the dependency between the piano and the harpsichord, so he asks himself whether keyboard music from the Classical period can still be part of the harpsichord repertoire and to what degree harpsichord performances of Classical compositions can be justified in performance practice. The problem is discussed especially in reference to music by W.A. Mozart. The article presents the history of views on the possibility of Mozart’s works to be performed on historical instruments. It also provides the most up-to-date information on the position of the harpsichord at the end of the 18th century. The last part of the article discusses this instrument’s role in the creative output of W.A. Mozart. It is mainly based on the latest knowledge Siegbert Rampe acquired in recent years.
Scriabin – piano music in the context of the composer’s creative ideology. Part 1
Authors: Piechnat Mateusz
Published: May 2019

The article is the first part of a cycle of texts devoted to the profile and piano works of Alexander Scriabin. The composer had an extraordinary piano talent and the ability of coloured hearing. He worked out an innovative musical language based on a unique harmonic style. He was an unprecedented visionary of art, he had knowledge on philosophical topics, he was also a mystic who wanted to save the mankind thanks to his creative output.
The article’s author asks questions about the reasons of this radical evolution of Scriabin’s musical language, the reflection of his personality and creative views and the connections of music with mystical experiences. As he believes, finding a way to a possibly authentic explanation of these issues may contribute to a better understanding of the composer’s creative intentions in the context of the artistic interpretation of his piano works.
The first part of the cycle presents the artist’s biography, his poetry and philosophical works. It discusses the most important events in his life, his music education and activity as a pianist and a composer, paying attention to the phenomenon called synesthesia and his idea-based creative aspirations. The analysis of the composer’s philosophical notes will allow for determining his worldview. As a result, the article will present the connections between the spheres of Scriabin’s activity, covering subsequent stages of his life and the transformation of his artistic views serving as a reference to the evolution of his musical language, which will be discussed in the next part of the cycle.
Lwówek Śląski in the arms of the muses. The activity of prince Constantin Hohenzollern’s private orchestra in the period of 1852–1869.
Authors: Milcarz Aleksandra
Published: May 2019

Prince Constantine (Friedrich Wilhelm Constantine) of Hohenzollern-Hechingen, a great music lover, aimed to create a good orchestra at his court. In the 1840s, he had already had a decent ensemble conducted by Thomas Täglichsbeck, which gave regular concerts in Hechingen. Villa Eugenia, the prince’s palace at that time, hosted numerous prominent figures from the world of music, first of all Franz Liszt; this acquaintance had a great influence on Constantine. After he abdicated and moved to his dominions in Silesia, in 1852 the prince decided to build a little palace with a concert hall for three hundred people in Lwówek Śląski (then German Löwenberg in Schlesien). Free weekly performances of the orchestra in the winter season (from November to April) in a provincial town of five thousand dwellers were something unheard of, so they soon attracted attention of music lovers. The artistic life of Lwówek was frequently described in the press in Wrocław, Leipzig and Berlin, it was also mentioned in foreign magazines. People praised the excellence of the orchestra, which achieved the peak of its capacities under the new chapelmaster Max Seifriz. He worked systematically on new repertoire and was particularly eager to perform compositions by young composers of the so-called New German School. The ensemble’s fame was consolidated by concerts whose guest conductors were the stars of the world of music of that time, i.e., Franz Liszt, Hector Berlioz and Richard Wagner. The activity of the orchestra and the time of musical glory of Lwówek came to a sudden end when prince Constantine died in 1869.