bluuebunny/crossref_metadata_2025_split huggingface dataset:
Influencia del biodiésel de aceite de fritura usado, sobre las emisiones: índice de opacidad
Authors: Mejía Regalado Antonio David , Cuty Clemente Eddy Roberto 
Published: May 2019

Contexto: Entre las fuentes de biodiésel, el aceite de fritura usado es un potencial combustible alternativo para reducir las emisiones de efecto invernadero de los motores diésel sin modificaciones tecnológicas considerables.
Método: Los experimentos se realizaron en condiciones estables, en un motor diésel de un cilindro de cuatro tiempos, mediante tres mezclas de combustible diésel puro con biodiésel obtenido de aceite de fritura usado (B10, B20 y B30) y combustible diésel comercial B5. El motor funcionó a velocidades variables entre 1000 - 1600 r.p.m., a plena carga y cargas variables del motor correspondientes a la potencia efectiva a 1600 r.p.m.
Resultados: Los resultados experimentales muestran que el índice de opacidad de B10, B20 y B30 a 1600 r.p.m., con velocidad nominal 1600 r.p.m. del motor a carga constante fue menor comparado con el combustible comercial B5 en 0,3 %, 24 % y 46 %, respectivamente. Sin embargo, al incrementar la carga del motor a velocidad constante de 1600 rpm, el índice de opacidad alcanzó su máximo valor para B20 comparado con los otros combustibles utilizados.
Conclusiones: Es viable el uso de biodiésel de aceite de fritura usado en mezclas con diésel puro y comercial para disminuir las emisiones tóxicas, como el material particulado (hollín) de los motores diésel en el medio ambiente. Por tanto, la reutilización de dicho aceite disminuye significativamente los problemas medioambientales.
Transaction Costs as a Source of Consumer Stockpiling
Authors: Garrod Luke , Li Ruochen , Wilson Chris M. 
Published: May 2019

Abstract
Consumers often stockpile goods to store for future consumption. The existing theoretical literature has focussed on a price-based explanation where stockpiling arises due to temporary price reductions. In contrast, this paper explores a transaction-cost-based explanation where consumers stockpile to avoid the need to incur future transaction costs. It shows how transaction costs lead to positive consumer stockpiling in an oligopoly equilibrium even when future prices are expected to fall. Relative to a no-stockpiling benchmark, such stockpiling lowers profits, but improves consumer and total welfare. Our results extend to the case of quantity discounts where stockpiling consumers pay relatively lower per-unit prices than non-stockpiling consumers, when purchasing multi-unit bundles.
Anatomy of Non-Employment Risk
Authors: Fugazza Carolina 
Published: May 2019

Abstract
This paper investigates how job separation and job-finding probabilities shape the non-employment risk across ages and working group characteristics. Improving on current methods, I estimate duration models for employment and non-employment separately. I then use the results to derive the individual age profiles of conditional transitions in and out of non-employment as well as the unconditional non-employment risk profile over the whole working life. This approach allows me to apply the decomposition of changes in individual non-employment risk. To date, this type of decomposition has only been used to study aggregate non-employment dynamics. I find that differences in job separation rates across ages underlie the observed age differences in non-employment risk. When differences between working groups are under consideration, the job finding probability is just as important as the job separation probability.
Do Labor Market Regulations Affect the Link between Innovation and Employment? Evidence from Latin America
Authors: Baensch Laura , Lanzalot Maria Laura , Lotti Giulia , Stucchi Rodolfo 
Published: May 2019

Abstract
This paper sheds light on how labor market regulations affect the relationship between different types of innovation and employment in Latin America. We estimate the effect of process and product innovation on employment growth using Enterprise Surveys for 14 Latin American countries. We calculate the model for the whole sample and then classify countries according to the rigidness of their labor market regulations. We find that: (i) product innovations have a positive impact on employment growth; (ii) process innovations do not affect employment growth; and (iii) more rigid labor market regulations (minimum wages and severance payments) reduce the effects of innovation.
Prenatal diagnosis of fetal hemivertebra in the first trimester
Authors: Parthenis Christos , Michalitsi Vasiliki , Chlapoutaki Chrysanthi , Souka Athena P. 
Published: May 2019

Abstract
Hemivertebra is a congenital spinal abnormality. The condition may affect one or multiple vertebrae. Hemivertebra occurs because of malformations or absence of the ossification centers. Most cases reported in the literature are diagnosed in the second trimester, usually after 22 weeks. It is very unusual and difficult for the hemivertebra to be detected at the first trimester.
Perspectives on the use of a health surveillance system for Guatemalan youth: a stakeholder analysis
Authors: Golub Sarah A. , Maza Reyes Juan Carlos , Williams David N. , Christensen Sinead , Reyes Lopez Andrea , Lopez Claudia , Calgua Erwin , Hassan Areej 
Published: May 2019

Abstract
In Guatemala, adolescent health indicators are collected using the Sistema Informático del Adolescente (SIA), a clinical survey developed by the Pan-American Health Organization. Recent analysis revealed significant gaps in data, limiting the ability of clinicians and policy makers to effectively address health disparities. Our objective was to explore adolescent health stakeholders’ perceptions of the SIA. We conducted semi-structured interviews with 22 clinic personnel recruited from six adolescent health clinics throughout Guatemala. Stakeholders included multi-disciplinary providers and key database personnel. Interviews were conducted in Spanish, recorded and transcribed; a coding scheme was developed using a phenomenological approach, and Dedoose was used for analysis. Four major themes emerged: (1) Collecting baseline adolescent health data was useful for prevention, diagnosis and treatment of adolescent health issues. (2) The SIA was instrumental in streamlining clinical care and informing the psychosocial needs of patients. (3) The questionnaire was time-intensive, repetitive and often problematic for data input/extraction. (4) Condensing the survey and using a web-based version may improve the system for future use. Our findings show that despite the use of a standardized system, multiple barriers contribute to gaps in comprehensive data collection in Guatemala. Refining the system may enhance adolescent health surveillance and improve quality of care in this vulnerable population.
Curative effects of Distemonanthus benthamianus Baillon. Trunk-bark extracts on enteropathogenic Escherichia coli 31-induced diarrhea in rats
Authors: William Yousseu Nana , Gilbert Ateufack , Shah Abdul Jabbar , Wahid Fazli , Marius Mbiantcha , Yameen Muhammad Arfat , Shah Syed Luqman , Bashir Kashif , Sajjad Wasim , Kuiate Jules-Roger , Albert Kamanyi , Khan Taous 
Published: May 2019

Abstract

Background

Distemonanthus benthamianus is used in the Western part of Cameroon to treat diarrheal episodes and infections. This study assessed its trunk-bark extracts activity against enteropathogenic Escherichia coli 31 (EPEC 31)-induced diarrhea in rats.

Methods
Aqueous and methanolic extracts were analyzed through high-performance liquid chromatography (HPLC). In vitro minimum inhibitory and bactericidal concentrations (MICs/MBCs) were evaluated on Enterococcus faecalis (ATCC 10,541), E. coli (ATCC 6539), Klebsiella pneumoniae (ATCC 13,883), Salmonella typhi (ATCC 6539) strains and on Proteus mirabilis, Pseudomonas aeruginosa (PA 01) and Shigella flexneri isolates using the microdilution method. Diarrhea was induced by inoculating rats with EPEC 31 (1.5 × 108
CFU/mL; p.o). Serum transaminases level assay and enzyme-linked immunosorbent assay (ELISA) for cytokines determination were performed. Hematoxylin–eosin (H–E) staining was used for intestinal tissue analysis.

Results
HPLC fingerprints of extracts showed presence of gallic acid and other unidentified compounds. The lowest MIC of 256 µg/mL was obtained with methanolic extract. At 100 mg/kg, both extracts significantly (p<0.001) inhibited diarrhea, with the methanolic extract being the most active. In addition, the methanolic extract significantly (p<0.001) increased the relative mass of the liver compared to negative control (Tween-DMSO 8%). The aqueous extract (100 mg/kg) significantly (p<0.01) increased alanine aminotransferase (ALT) serum concentration; while the methanolic extract (100 mg/kg) exhibited similar effect over aspartate aminotransferase (AST). At 50 and 100 mg/kg, the methanolic extract significantly (p<0.05 and p<0.01) decreased the Interleukin-1β (IL-1β) serum level, compared to negative control (Tween-DMSO 8%). Serum level of tumor necrosis factor alpha (TNF-α) significantly (p<0.001) decreased with 100 mg/kg of aqueous extract and all doses of methanolic extract. Inhibition of inflammatory cells tissue infiltration and epithelial regeneration was highly noticed in the ileum and colon of extracts-treated rats than in ciprofloxacin-treated animals.

Conclusion
These findings suggest that D. benthamianus trunk-bark extracts displayed therapeutic effects against infectious diarrhea in rats.
Perfect 1-factorizations
Authors: Rosa Alexander 
Published: May 2019

AbstractLetGbe a graph with vertex-setV=V(G) and edge-setE=E(G). A 1-factorofG(also calledperfect matching) is a factor ofGof degree 1, that is, a set of pairwise disjoint edges which partitionsV. A 1-factorizationofGis a partition of its edge-setEinto 1-factors. For a graphGto have a 1-factor, |V(G)| must be even, and for a graphGto admit a 1-factorization,Gmust be regular of degreer, 1 ≤r≤ |V| − 1.One can find in the literature at least two extensive surveys [69] and [89] and also a whole book [90] devoted to 1-factorizations of (mainly) complete graphs.A 1-factorization ofGis said to beperfectif the union of any two of its distinct 1-factors is a Hamiltonian cycle ofG. An early survey on perfect 1-factorizations (abbreviated as P1F) of complete graphs is [83]. In the book [90] a whole chapter (Chapter 16) is devoted to perfect 1-factorizations of complete graphs.It is the purpose of this article to present what is known to-date on P1Fs, not only of complete graphs but also of other regular graphs, primarily cubic graphs.
Tribonacci numbers and primes of the form p = x
2 + 11y
2
Authors: Evink Tim , Helminck Paul Alexander 
Published: May 2019

Abstract
In this paper we show that for any prime number p not equal to 11 or 19, the Tribonacci number T

p−1 is divisible by p if and only if p is of the form x
2 + 11y
2. We first use class field theory on the Galois closure of the number field corresponding to the polynomial x
3 − x
2 − x − 1 to give the splitting behavior of primes in this number field. After that, we apply these results to the explicit exponential formula for T

p−1. We also give a connection between the Tribonacci numbers and the Fourier coefficients of the unique newform of weight 2 and level 11.
Basic semirings
Authors: Chajda Ivan , Länger Helmut 
Published: May 2019

AbstractBasic algebras were introduced by Chajda, Halaš and Kühr as a common generalization of MV-algebras and orthomodular lattices, i.e. algebras used for formalization of non-classical logics, in particular the logic of quantum mechanics. These algebras were represented by means of lattices with section involutions. On the other hand, classical logic was formalized by means of Boolean algebras which can be converted into Boolean rings. A natural question arises if a similar representation exists also for basic algebras. Several attempts were already realized by the authors, see the references. Now we show that if a basic algebra is commutative then there exists a representation via certain semirings with involution similarly as it was done for MV-algebras by Belluce, Di Nola and Ferraioli. These so-called basic semirings, their ideals and congruences are studied in the paper.
Mittag-Leffler stability for non-instantaneous impulsive Caputo fractional differential equations with delays
Authors: Agarwal Ravi , Hristova Snezhana , O’Regan Donal 
Published: May 2019

Abstract
Caputo fractional delay differential equations with non-instantaneous impulses are studied. Initially a brief overview of the basic two approaches in the interpretation of solutions is given. A generalization of Mittag-Leffler stability with respect to non-instantaneous impulses is given and sufficient conditions are obtained. Lyapunov functions and the Razumikhin technique will be applied and appropriate derivatives among the studied fractional equations is defined and applied. Examples are given to illustrate our results.
Disjoint hypercyclic weighted translations on locally compact hausdorff spaces
Authors: Wang Ya , Zhou Ze-Hua 
Published: May 2019

Abstract
Let G be a locally compact second countable Hausdorff space with a positive regular Borel measure λ, where λ is invariant under a continuous injective mapping φ : G → G. We characterize the disjoint hypercyclicity of finite weighted translations generated by φ acting on the weighted space Lp
(G, ω) (1 ≤ p < ∞).
Cohomology of torus manifold bundles
Authors: Dasgupta Jyoti , Khan Bivas , Uma Vikraman 
Published: May 2019

Abstract
Let X be a 2n-dimensional torus manifold with a locally standard T ≅ (S
1)
n
action whose orbit space is a homology polytope. Smooth complete complex toric varieties and quasitoric manifolds are examples of torus manifolds. Consider a principal T-bundle p : E → B and let π : E(X) → B be the associated torus manifold bundle. We give a presentation of the singular cohomology ring of E(X) as a H
*(B)-algebra and the topological K-ring of E(X) as a K
*(B)-algebra with generators and relations. These generalize the results in [17] and [19] when the base B = pt. These also extend the results in [20], obtained in the case of a smooth projective toric variety, to any smooth complete toric variety.
Crystal structure of (4S,4aS,6aR,6bR,12aS,12bR,14aS,14bR)-3,3,6a,6b,9,9,12a-heptamethyloctadecahydro-1H,3H-4,14b-ethanophenanthro[1,2-h]isochromene-1(6bH)-one, C30H48O2
Authors: He Kang , Fan Lin-Lin , Wu Tian-Tai , Zhang Qi-Long , Zou Juan 
Published: May 2019

Abstract
C30H48O2, orthorhombic, P212121 (no. 19), a = 10.8192(12) Å, b = 16.4915(17) Å, c = 28.832(3) Å, V = 5144.4(10) Å3, Z = 4, R
gt(F) = 0.0582, wR
ref(F
2) = 0.1169, T = 293(2) K.
Essential and trace elements status in the indigenous Ethiopian tuber crops
Authors: Melkegna Tamene Hailu , Chaubey Ashok Kumar , Jonah Sunday Adesunloye , Ahmed Yusuf Aminu , Abubakar Nuruddeen 
Published: May 2019

Abstract
The objective of the study is multi elemental analysis of four indigenous Ethiopian tuber crops using instrumental neutron activation analysis (INAA) technique in order to get scientific evidences about the status of essential, trace and non-essential elemental compositions. The samples were collected from Southern and South-western parts of Ethiopia. The irradiation and measurement were performed by using irradiation and counting facilities of the Nigeria Nuclear Reactor-1 (NIRR-1) and a HPGe detector setup at the Centre for Energy Research and Training (CERT), Ahmadu Bello University (ABU), Zaria, Nigeria. A total of 17 elements were determined at various concentration levels. The highest concentrations of K, Mg, Mn and Zn were found in Colocasia esculenta (L.) Schott, whereas; the concentrations of essential and trace elements; Ca, K, Mg, Na, Cl, Mn, and Zn were found to be high in the native Coccinia abyssinica (Lam.) Cogn tuber. The estimated daily intake values of the constituent elements from the consumption of these crops are below upper tolerable limits set by international organizations such as WHO and FAO.
Impact of Phase Transformation in WO3 Thin Films at Higher Temperature and its Compelling Interfacial Role in Cu/WO3/p–Si Structured Schottky Barrier Diodes
Authors: Marnadu R. , Chandrasekaran J. , Vivek P. , Balasubramani V. , Maruthamuthu S. 
Published: May 2019

Abstract
Inter-connected network grains of tungsten trioxide (WO3) thin films were deposited on glass using a jet nebulizer spray pyrolysis (JNSP) technique by varying the substrate temperature at 350, 400, 450 and 500 °C. Phase transformation (monoclinic to orthorhombic) was observed during the film growth through X-ray diffraction (XRD) analysis. Field emission scanning electron microscope (FE-SEM) images revealed a better grain growth with smooth surface for 400 °C. The WO3 film deposited at 400 °C exhibits minimum band gap and maximum optical conductivity of 3.2 eV and 5.8 × 1014 (Ω.cm)−1. From the current-voltage (I–V) characteristics, the mean electrical conductivity is found to increase gradually and the activation energy reduced at higher substrate temperature. Cu/WO3/p–Si structured Schottky barrier diodes (SBDs) have been fabricated with different substrate temperature and it was tested under variable device temperatures ranging from 30 to 170 °C. The experimental results of all SBDs indicated a linear reduction in the ideality factor (n) with a small increment in effective barrier height (Φ
B) with increase in device temperature, which is due to lateral inhomogeneity’s at the interface. Moreover, the minimum n value of 2.89 and their corresponding Φ
B of 0.71 eV were recorded for device temperature at 170 °C. Compared with other SBDs, the device fabricated at 400 °C demonstrated a better thermal stability and device performance.
On the Spatial Variation of the Microstructure and Microhardness Properties of Nickel-Based Superalloy René 142 Fabricated via Scanning Laser Epitaxy (SLE)
Authors: Basak Amrita , Yang Yunpei , Das Suman 
Published: May 2019

Abstract
This article seeks to investigate and characterize the spatial variation of the microstructure and microhardness properties of René 142, a high-γ′ nickel-based superalloy, fabricated through single-pass depositions using scanning laser epitaxy (SLE), a laser powder bed fusion (LPBF)–based additive manufacturing (AM) process. Various advanced material characterization techniques such as optical microscopy, scanning electron microscopy, and Vickers microhardness measurements are employed to thoroughly characterize the SLE-fabricated René 142 specimens. Whereas optical microscopy analyses reveal that the primary dendritic arm spacing (PDAS) remains relatively constant, scanning electron microscopy investigations demonstrate that the size of the γ′ precipitates increase as the scan progresses. Microhardness measurements indicate that the hardness values remain unaffected along the scan direction. Through this study, it is demonstrated that the microstructure and the microhardness properties of the AM-fabricated René 142 deposits are strong functions of the spatial location.
The Operationalization of Ernesto Laclau’s Theory of Populism: Case of the Political Party “The Way of Courage”
Authors: Jonutis Karolis 
Published: May 2019

This article aims to explain the rise of the Lithuanian political party “The Way of Courage” using Ernesto Laclau’s discourse theory of populism, in which populism is understood as a logic of collective identity formation. The advantages of this theoretical approach are revealed by comparing it with other tendencies of conceptualizing populism. In addition, this article is an attempt to solve the main disadvantage of E. Laclau’s theory – its high level of abstractness, understood as an obstacle for operationalization. Therefore, various possibilities of combining E. Laclau’s theory with other methodological perspectives are discussed, and a new research model is suggested, which is later applied in the discourse analysis of the political party “The Way of Courage.”
The Concept of “Internal Colonization” and Its Application in a Comparative Analysis of (Post)Soviet States
Authors: Čepaitienė Rasa 
Published: May 2019

This article discusses a direction of sociocultural studies – the cultural history of natural resources – and the possibilities of its application in examining the causes of inequality and social exclusion in post-Soviet Lithuania. This theoretical-methodological approach assumes a strong interdependence shared between the extraction of natural resources, a state’s political system and institutions as well as certain sociocultural provisions. In exploring the concept of “internal colonization,” developed by historian of culture Alexander Etkind and other authors, this article sets guidelines for a comparative analysis of the sociopolitical structure of post-Soviet countries (especially Russia and Lithuania). Some initial hypotheses regarding the trends, differences, and similarities of post-Soviet societies in the long historical perspective, from the 16th century up to our time, are presented for further analysis. This article concludes that this methodological approach could be sufficiently promising in explaining the specifics of the socioeconomic development of independent Lithuania, in particular by applying the hypothesis of a “secondary internal colonization,” which has been raised during the course of the investigation.
The Transformation of the Concept of an Urban Ecosystem: Classical and Modern Urban Ecology
Authors: Žiemelis Darius 
Published: May 2019

Contemporary trends in urban development indicate that its processes rarely observe ecocentric perspectives, under which nature is considered as a value. This concept is represented by modern urban ecology. Meanwhile, the urban ecosystem, as a concept of a human system, is represented by classical urban ecology. The existence of different urban ecosystem concepts encourages a closer look at not only the differences between these concepts but also the circumstances that have led to this transformation process. The aim of this article is to analyze the concepts of an urban ecosystem in classical and modern urban ecology, focusing not only on the explication of the content of the concepts of urban ecosystem, but also on the social, cultural and economic conditions of the emergence of different concepts. This article reveals that the separation of urban ecosystem concepts was determined by the different sociocultural environment in which classical urban ecology and contemporary urban ecology have emerged. From the point of view of modern urban ecology, in order to explain the reasons for the emergence of global urban development problems and to search for solutions to them, the conceptual legacy of classical urban ecology, due to its anthropocentric orientation, not only cannot be of use anymore but also hinders in this search – that is, instead of solving problems, it makes them even worse.