bluuebunny/crossref_metadata_2025 huggingface dataset:
La distribution des éléments alcalins Li, Na, K, Rb, dans les minéraux essentiels des granites et granodiorites du sud de la Corse
Authors: Carron Jean-Paul , Lagache Martine
Published: April 2019

The partition of major and minor alkali elements between the main minerals of 15 biotite-granites and 15 amphibole-biotite-granodiorites agrees with an equilibrium state due to ion exchange mechanisms. According to experimental data, the Na and K distribution between coexisting feldspars indicates an equili¬ brium temperature of 550° C for the granites, and 475° C for the granodiorites. For trace elements, weight partition coefficients have been calculated between K-feldspars (F), plagioclases (P), biotites (B) and amphiboles (A) : for lithium D[B/A] = 10 and D[P/F] = 4.3 ; for rubidium D[F/P] = 12 (the last two coefficients are established for all samples taken together). The rubidium partition between biotites and K feldspars, defined by the ratios Rb/(K + Na) for each mineral, makes it possible to split the two rock types, and to attribute to them temperatures differing by approximately 50° C. Most results for Li and Rb are explained by comparing their ionic radii with the size of suitable sites in the various minerals.
SOLVING THE STOKES PROBLEM ON A MASSIVELY PARALLEL COMPUTER
Authors: Axelsson O. , Barker V. A. , Neytcheva M. , Polman B.
Published: April 2019

We describe a numerical procedure for solving the stationary two-dimensional Stokes problem based on piecewise linear finite element approximations for both velocity and pressure, a regularization technique for stability, and a defect‐correction technique for improving accuracy. Eliminating the velocity unknowns from the algebraic system yields a symmetric positive semidefinite system for pressure which is solved by an inner‐outer iteration. The outer iterations consist of the unpreconditioned conjugate gradient method. The inner iterations, each of which corresponds to solving an elliptic boundary value problem for each velocity component, are solved by the conjugate gradient method with a preconditioning based on the algebraic multi‐level iteration (AMLI) technique. The velocity is found from the computed pressure. The method is optimal in the sense that the computational work is proportional to the number of unknowns. Further, it is designed to exploit a massively parallel computer with distributed memory architecture. Numerical experiments on a Cray T3E computer illustrate the parallel performance of the method.
THE MAIN HASEMAN TYPE BOUNDARY VALUE PROBLEM FOR METAANALYTIC FUNCTION IN THE CASE OF CIRCULAR DOMAINS
Authors: Fatulaev B. F.
Published: April 2019

In the presented work a main Haseman type boundary value problem is investigated in the class of metaanalytic functions in the case of circular domains. With the help of Schwartz equation for circumference the initial problem can be reduced to the totality of two ordinary Haseman problems for analytic functions. Besides, the picture of solvability of the problem depending on values of indexes of coefficients of boundary value conditions is is investigated in this work.
SIMPLE ALGORITHM'S FOR THE CALCULATION OF HEAT TRANSPORT PROBLEM IN PLATE
Authors: Kalis H. , Kangro I.
Published: April 2019

The approximations of some heat transport problem in a thin plate are based on the finite volume and conservative averaging methods [1,2]. These procedures allow one to reduce the two dimensional heat transport problem described by a partial differential equation to an initial‐value problem for a system of two ordinary differential equations (ODEs) of the first order or to an initial‐value problem for one ordinary differential equations of the first order with one algebraic equation. Solution of the corresponding problems is obtained by using MAPLE routines “gear”, “mgear” and “lsode”.
ASYMPTOTICAL ANALYSIS OF ONE DIMENSIONAL GAS DYNAMICS EQUATIONS
Authors: Krylovas A. , Čiegis R.
Published: April 2019

A method of averaging is developed for constructing a uniformly valid asymptotic solution for weakly nonlinear one dimensional gas dynamics systems. Using this method we give the averaged system, which disintegrates into independent equations for the non‐resonance systems. Conditions of the resonance for periodic and almost periodic solutions are presented. In the resonance case the averaged system is solved numerically. Some results of numerical experiments are given.
SOLUTION OF TWO‐DIMENSIONAL MULTI‐INTERFACE STEFAN PROBLEM BY THE METHOD OF DYNAMIC ADAPTATION
Authors: Mazhukin V. I. , Chuiko M. M.
Published: April 2019

In the present work a method of numerical solution of multi‐interface two-dimensional Stefan problem with explicit tracking of the interfaces in the domains of arbitrary form is considered. The method is based on the idea of dynamic adaptation of the calculated grid by means of transition to an arbitrary non-stationary coordinate system. The coordinate system transformation is controlled by the solution. The method is described by using the example of the problem that is typical for treatment of materials with concentrated energy fluxes.
ON THE FIRST BOUNDARY VALUE PROBLEM FOR THE CLASS OF ELLIPTIC SYSTEMS DEGENERATING AT AN INNER POINT
Authors: Rutkauskas S.
Published: April 2019

The Dirichlet type problem for the weakly related elliptic systems of the second order degenerating at an inner point is discussed. Existence and uniqueness of the solution in the Holder class of the vector‐functions is proved.
COMPARATIVE ANALYSIS OF SELECTED PROBABILISTIC CUSTOMER LIFETIME VALUE MODELS IN ONLINE SHOPPING
Authors: Jasek Pavel , Vrana Lenka , Sperkova Lucie , Smutny Zdenek , Kobulsky Marek
Published: April 2019

The selection of a suitable customer lifetime value (CLV) model is a key issue for companies that are introducing a CLV managerial approach in their online B2C relationship stores. The online retail environment places CLV models on several specific assumptions, e.g. non-contractual relationship, continuous purchase anytime, variable-spending environment. The article focuses on empirical statistical analysis and predictive abilities of selected probabilistic CLV models that show very good results in an online retail environment compared to different model families. For comparison, eleven CLV models were selected. The comparison has been made to the online stores’ datasets from Central and Eastern Europe with annual revenues of hundreds of millions of euros and with almost 2.3 million customers. Probabilistic models have achieved overall good and consistent results on the majority of the studied transactional datasets, with BG/NBD and Pareto/NBD models that can be considered stable with significant lifts from the baseline Status quo model. Abe's variant of Pareto/NBD have underperformed multiple criterions and would not be fully useful for the studied datasets without further improvements. In the end, the authors discuss the deployment implications of selected CLV models and propose further issues for future research to address.
The Splashback Radius of Planck SZ Clusters*
Authors: Zürcher Dominik , More Surhud
Published: April 2019

We present evidence for the existence of the splashback radius in galaxy clusters selected using the Sunyaev–Zeldovich effect, a sample unaffected by systematics related to cluster finding in the optical wavelength range. We show that the deprojected cross-correlation of galaxy clusters found in the Planck survey with galaxies detected photometrically in the Pan-STARRS survey shows a sharp steepening feature (a logarithmic slope steeper than −3), which we associate with the splashback radius. We infer the 3D splashback radius for the SZ cluster sample to be

, where the cluster sample has an average halo mass of M
500c
 = 3.0 × 1014

at an average redshift of z = 0.18. The inferred value of the splashback radius appears marginally consistent with the expected location for dark matter halos in the standard cold dark matter paradigm. However, given the limited precision of our measurements, we cannot conclusively confirm or rule out the smaller splashback radius measured so far in the literature for optically selected galaxy clusters. We show that the splashback radius does not depend on the galaxy magnitude for galaxies fainter than

and is present at a consistent location in galaxy populations divided by color. The presence of the splashback radius in the star-forming galaxy population could potentially be used to put lower limits on the quenching timescales for galaxies. We can marginally rule out the contamination of the star-forming galaxy sample by quenched galaxies, but the results would need further verification with deeper data sets.
X-Ray and Optical Monitoring of State Transitions in MAXI J1820+070
Authors: Shidatsu Megumi , Nakahira Satoshi , Murata Katsuhiro L. , Adachi Ryo , Kawai Nobuyuki , Ueda Yoshihiro , Negoro Hitoshi
Published: April 2019

We report results from the X-ray and optical monitoring of the black hole candidate MAXI J1820+070 (=ASSASN-18ey) over the entire period of its outburst from 2018 March to October. In this outburst, the source exhibited two sets of “fast rise and slow decay”-type long-term flux variations. We found that the 1–100 keV luminosities at two peaks were almost the same, although a significant spectral softening was only seen in the second flux rise. This confirms that the state transition from the low/hard state to the high/soft state is not determined by the mass accretion rate alone. The X-ray spectrum was reproduced with the disk blackbody emission and its Comptonization, and the long-term spectral variations seen in this outburst were consistent with a disk truncation model. The Comptonization component, with a photon index of 1.5–1.9 and electron temperature of ≳40 keV, was dominant during the low/hard state periods, and its contribution rapidly decreased (increased) during the spectral softening (hardening). During the high/soft-state period, in which the X-ray spectrum became dominated by the disk blackbody component, the inner disk radius was almost constant, suggesting that the standard disk was present down to the innermost stable circular orbit. The long-term evolution of optical and X-ray luminosities and their correlation suggest that the jets substantially contributed to the optical emission in the low/hard state, while they are quenched and the outer disk emission dominated the optical flux in the intermediate state and the high/soft state.
A Data-constrained Magnetohydrodynamic Simulation of Successive Events of Blowout Jet and C-class Flare in NOAA AR 12615
Authors: Nayak Sushree S. , Bhattacharyya R. , Prasad A. , Hu Qiang , Kumar Sanjay , Joshi B.
Published: April 2019

Magnetohydrodynamic simulation is carried out for the NOAA AR 12615 in the time span t ∈ {05:48, 06:18} UT on 2016 December 5; covering events of a blowout jet and a C1.2 flare. The events are selected based on the small interval between their occurrences, which provides us with an opportunity to explore two energetically different events of magnetic reconnection (MR) within the run time of a single magnetohydrodynamic (MHD) simulation. The simulation is initiated with magnetic field extrapolated from the vector magnetogram provided by the Helioseismic Magnetic Imager/Solar Dynamics Observatory, using a non-force-free approximation. The extrapolated Lorentz force is found to decay at a rate faster than the volume current density, making the higher corona to be effectively force-free while the Lorentz force affects only the lower corona and the photosphere—a desirable feature that agrees with the contemporary understanding. For the simulation, the plasma is idealized to be incompressible, thermally homogeneous and having perfect electrical conductivity. The results affirm MRs near a set of two three-dimensional (3D) magnetic nulls to be responsible for initiating the jet. Moreover, a flux rope located near the nulls contributes to the jet by changing its magnetic field lines from an anchored to an open topology. The scenario agrees with the standard mini-filament breakout model for blowout jets and provides its first demonstration from a 3D data-constrained MHD simulation where the computational output is reconciled with magnetogram(s) only once. The generation of flare ribbons is attributed to reconnections at a 3D null and a quasi-separatrix layer (QSL), highlighting the importance of topological complexity in flare initiation.
The Role of a Magnetic Topology Skeleton in a Solar Active Region
Authors: Guo Juan , Wang Huaning , Wang Jingxiu , Zhu Xiaoshuai , Dai Xinghua , Huang Xin , He Han , Yan Yan , Zhao Hui
Published: April 2019

We investigate the 3D magnetic topology in the active region NOAA 11719 nine hours before and after a flare–coronal mass ejection (CME) event on 2013 April 11. The extrapolated 3D coronal magnetic field is computed employing a boundary integrated model, and a complex magnetic topology skeleton comprising five fairly robust null points and their relevant structures are revealed with a mathematical method based on a Poincaré index of isolated 3D null points. Comparative analyses show that the magnetic topology skeleton in this active region determines geometries of post-flare loops and flare ribbons, and characterizes the initial stage of the CME. The present work demonstrates that the magnetic topology skeleton plays an important role in the process of the flare–CME eruption.
The Flare Catalog and the Flare Activity in the Kepler Mission
Authors: Yang Huiqin , Liu Jifeng
Published: April 2019

We present a flare catalog of the Kepler mission using the long-cadence data of Data Release 25. This catalog comprises 3420 flare stars and 162,262 flare events. A comparison shows that the flare catalogs of previous studies are seriously polluted by various false-positive signals and artifacts. The incidence of flare stars rises with decreasing temperature, which accords with the theoretical analysis. The flare frequency distributions (FFDs) from F-type stars to M-type stars obey a power-law relation with α ∼ 2, indicating that they have the same mechanism on generating flares. The remarkable incidence and the deviation of FFDs on A-type flare stars imply that they generate flares in a different way. The activity–rotation relation is consistent with previous studies at low temperature bands, whereas it becomes dispersive with increasing temperature. Combined with the Gyrochronology, we find that the mixing of stars of two different dynamos gives rise to the dispersion. We thereby propose a scenario on understanding the activity–rotation relation across the Hertzsprung-Russell diagram. Based on the scenario and the correspondence of dynamo with regard to activity and rotation, we suggest a new expression on the activity–rotation relation, in which the segmentation is on the basis of the dynamo rather than the rotation period. The rotation distribution of flare stars shows that about 70% of flare stars rotate faster than 10 days and the rate approaches 95% at 30 days. Based on the incidence and the rotation distribution of flare stars, we estimate that a superflare with energy ∼1034 erg occurs on the Sun at least once in 5500 yr.
CAFE-R: A Code That Solves the Special Relativistic Radiation Hydrodynamics Equations
Authors: Rivera-Paleo F. J. , Guzmán F. S.
Published: April 2019

We present a 3D special relativistic radiation hydrodynamics code. It uses the radiative inversion scheme with the M1 closure relation for the radiation equations, which allows the treatment of a wide range of optical depth, temperature, and opacity. The radiation field is treated in the graybody approximation. We present the standard 1D and 2D tests that include both optically thin and thick scenarios, as well as hydrodynamical and radiation-pressure-dominated configurations. As an application in 3D, we show the evolution of a jet driven by radiation hydrodynamics with a helical perturbation. The code is expected to allow the exploration of scenarios in high-energy astrophysics where the radiation is important, like sources of gamma-ray bursts.
Origin of the Excess of High-energy Retrograde Stars in the Galactic Halo
Authors: Matsuno Tadafumi , Aoki Wako , Suda Takuma
Published: April 2019

We report on the very low α-element abundances of a group of metal-poor stars with high orbital energy and with large retrograde motion in the Milky Way halo, whose excess has been reported recently from metallicity and kinematics. We constructed a sample of halo stars with measured abundances and precise kinematics, including ∼880 stars with [Fe/H] < −0.7, by crossmatching the Stellar Abundances for Galactic Archaeology database to the second data release of Gaia. Three regions in the energy-angular momentum space have been selected: the innermost halo, Gaia Enceladus/Sausage, and the high-energy retrograde halo. While the innermost halo and Gaia Enceladus regions have chemical abundances consistent with high- and low-α populations in the halo, respectively, chemical abundances of stars in the high-energy retrograde halo are different from the two populations; their [X/Fe], where X represents Na, Mg, and Ca, are even lower than those in Gaia Enceladus. These abundances, as well as their low mean metallicity, provide a new support for the idea that the retrograde component is dominated by an accreted dwarf galaxy which has a longer star formation timescale and is less massive than Gaia Enceladus/Sausage.
Desenvolvimento de pão francês light com redução de 50% de sódio.
Authors: Carvalho Juliana Domingues dos Santos , Meleiro Vitor Da Cruz , Almeida Gisele Lara de , Costa Wesley Cardoso da
Published: April 2019

O presente trabalho teve como objetivo desenvolver uma formulação de pão francês com 50% de redução no teor de sódio (Na+), avalição sensorial do produto sem veículo e com veículo (margarina) e a avaliação estatística dos resultados. As análises físico-químicas seguiram a metodologia estabelecida pelo Instituto Adolfo Lutz (2008). Já para a análise sensorial foi utilizado um método afetivo, utilizando 79 provadores para a primeira avaliação e para a segunda 95 provadores, tendo como referência mínima de aceitação o índice de 70%. Para os resultados de composição centesimal o produto atende a especificação legal. Na avaliação dos parâmetros sensoriais percebe-se que os índices de aceitação dos produtos sofrem interferência quando são oferecidos com veículo (margarina). Assim com base nos resultados obtidos neste projeto mostram que é possível desenvolver um produto com 50% de redução de sódio, dentro do padrão legal estabelecido.
Egg parasitoids of the tea green leafhopper Empoasca onukii (Hemiptera, Cicadellidae) in Japan, with description of a new species of Anagrus (Hymenoptera, Mymaridae)
Authors: Triapitsyn Serguei V. , Adachi-Hagimori Tetsuya , Rugman-Jones Paul F. , Barry Adema , Abe Aoba , Matsuo Kazunori , Ohno Kazuro
Published: April 2019

Fairyfly (Hymenoptera, Mymaridae) egg parasitoids of the tea green leafhopper Empoasca (Matsumurasca) onukii Matsuda (Hemiptera, Cicadellidae), an economically important pest in Asia of the tea plant,Camelliasinensis, were identified from specimens reared in Japan. Using a combination of genetic and morphological evidence, Anagrus (Anagrus) rugmanjonesi Triapitsyn & Adachi-Hagimori,sp. n., is described and illustrated. It is shown to be different from the most similarA.turpanicusTriapitsyn & Hu, anegg parasitoid of a leafhopper pest of cultivated grapes which is known from Xinjiang Uyghur Autonomous Region in China. Mitochondrial and nuclear ribosomal DNA sequence data provide clear evidence for the separation ofA.rugmanjonesifromA.turpanicusand other members of theAnagrusincarnatusHaliday species complex. A key to females of the Japanese species ofAnagrusHaliday is given. Two other species of Mymaridae,Aresconenocki(Subba Rao & Kaur) andStethyniumempoascaeSubba Rao, are also identified, albeit the latter one only tentatively. Both latter taxa are newly recorded from Japan, andE.onukiirepresents their new host association.
Blood lactate responses to plyometric training in cricket players of different maturity level: a randomised controlled trial
Authors: Singla D. , Shareef M.Y. , Hussain M.E.
Published: April 2019

Previous studies commonly examined the acute effect of plyometric exercise on blood lactate. To the best of our knowledge, no study has examined the effect of short-term plyometric training on blood lactate levels of cricket players. To investigate the effect of an 8 week plyometric training program on blood lactate concentration in cricket players of different maturity level. 55 healthy male cricket players (aged 14-35 years) were categorised into 14-17, 18-25 and 26-35 groups. Blood lactate concentration (BLAC) was assessed before and after 8 weeks of the intervention period. Regardless of the maturity level, a significant reduction in BLAC was observed in the experimental cricketers (P<0.05) in response to 8 weeks of training. Blood lactate responses did not vary significantly in 14-17, 18-25 and 26-35 groups of cricket players following plyometric training. Plyometric training significantly reduced BLAC in cricket players despite non-significant differences amongst 14-17, 18-25 and 26-35 groups. Plyometric training could be recommended for adolescent (14-17) and adult cricketers (18-25 and 26-35) for improving their physiological capacities so as to develop optimal performance.
Use of insecticides and other capturing techniques of bush cricket (Tettigonia viridissima): dietary implications among population of Tubah, Cameroon
Authors: Sonchieu J. , Roméo H.C. , Wenceslas Y. , Mireille N.K.
Published: April 2019

Worldwide consumption of insects is today regarded as a good source of protein supplementation. This study aims at exploring the dietary factors, cooking, preservation techniques, and harvesting methods of longhorn grasshoppers (
Tettigonia viridissima
). The survey was conducted from September 2016 to January 2017 in Tubah council (North-West Region, Cameroon) using a semi-structured questionnaire, which was administered to two hundred
T. viridissima
harvesters. Chi-square was used to compare variables in a particular group for related measured factors. The main objective of the questionnaire was to find out how longhorn grasshoppers were harvested and consumed in the community. The harvesting of grasshoppers included three major techniques: hand picking (53%), trapping (29%) and use of insecticides (18%). Insecticides used (cypermethrin and deltamethrin) are from class II chemical toxicity. Dietary factors focused on: cooking methods (frying, roasting and boiling) and methods of preservation (sun drying and refrigerating). For the local population, grasshoppers constitute a good source of proteins from the month of September to January, but its safety is a concern as far as insecticides are used in harvesting them. Therefore, the population should be educated on the health risks linked to this malpractice method and the local and national authorities informed.
A One Health Perspective on Q Fever
Authors: Cruz Rita , Vasconcelos-Nobrega Carmen , Esteves Fernando , Coelho Catarina , Ferreira Ana Sofia , Santos Carla , Mega Cristina , Coelho Ana C. , Vala Helena , Mesquita João R.
Published: April 2019

Q fever, a widespread zoonotic disease caused by Coxiella burnetiid, produces a complex and polymorphic disease in humans. As a zoonotic disease, control in animals will influence the level of disease seen in humans, thus resulting in interesting one health perspectives for disease control. Here the authors describe the clinical manifestations in animals and humans, as well as the current diagnostic methods available and the strategies for disease control. A review on the published information regarding Q fever as a disease with impact for veterinary public health and public health is presented.
Mobile News Experience
Authors: Li Wendi , Xu Xiaoge
Published: April 2019

Mobile has become a mainstream medium for news consumption on the go. To cater to the growing demand for mobile news, traditional news providers have switched from “mobile too” to “mobile first” strategies. To enhance mobile news communication, it is imperative for mobile news providers to stay abreast of mobile news consumers' changing expectations of mobile news experience in a news app. It is equally imperative to identify the gap between news consumers' expectations and what mobile news experience is embedded in a mobile news app. Using a mobile experience index, the authors of this chapter have located the venue and extent of the gap through conducting a survey of mobile news app users and a comparative analysis of indicators of mobile news experience in selected news apps.
CSR Initiatives of Family Firms
Authors: Guajardo Salvador S. , Correa-Flores Aurora , Mojarro-Durán Barbara I. , Fraile Alfonso Ernesto Benito
Published: April 2019

This chapter studies the corporate social responsibility (CSR) initiatives of the leading Mexican business groups. Investigating in family firms is essential because they represent the world's most predominant form of organization. One way in which family firms organize their economic activity and structure are business groups. Mexican family firms conform to business groups within the same family. The purpose of this chapter is to inquiry the corporate social initiatives emanating from the main Mexican business groups. Through quantitative and qualitative exploratory research, findings show that business groups in Mexico orient their corporate social initiatives into internal and external strategies, and tend to distribute disproportionally the amount of initiatives and money invested among each of its affiliates. Also, firms affiliated to a business group have a higher probability than unaffiliated firms of being classified as “sustainable,” according to the IPC Sustainable Index.
Transparency of Information in Spanish Family Businesses and Its Role in Online Reputation Management
Authors: Vallejo Marcelo , Vallvey Fernando Martínez , Rivero Alfonso José López
Published: April 2019

Corporate reputation is one of the main assets to compete successfully in the markets today, which requires its proper management. One of the main factors that determine the level of reputation of a company is transparency, due to its effects on the acquisition of the necessary information in order to maximize the effectiveness of stakeholders´ decisions. In order to know the current situation of information transparency provided by the family businesses of Castile and León, a study has been carried out, analyzing the degree of compliance with the requirements established by Royal Decree Law of 18/2017 of 24 November in 35 family businesses in the region. This law establishes the social and environmental information that companies with over 500 employees are legally obliged to provide.
Roadblocks to Bilingualism
Authors: Strid John Evar , Cohen James A. , Gathings Autumn , Stepter Raven , Taylor Amor
Published: April 2019

Most teacher candidates have little experience with learning other languages. They therefore become cogs in the assimilationist machine that causes immigrants to lose native languages and become monolingual in English (Rumbaut, Massey, & Bean, 2006). In a time of devaluing immigrants (and their languages) and failure on the part of most Americans to learn other languages, educators need to focus on the role of other languages in promoting multicultural understanding and to increase language learning in the US. This chapter examines bilingual teacher candidates' experiences with language learning. For four years, students studying for ESL/bilingual licensure were asked to rate their language abilities, finding that 30% rated themselves as bilingual, with 70.43% of bilinguals describing themselves as heritage speakers. The authors report the overall findings as well as the bilingual heritage speaker candidates' own words on their experiences with language learning and maintaining their bilingualism.
Resource vs. Deficit Views About English Language Learners in Classroom Practice
Authors: Jeong Heeok
Published: April 2019

Grounded in a critical sociocultural perspective, this ethnographic case study explores two ELL teachers' views about ELLs and their classroom practices over one academic year using linguistically oriented critical discourse analysis methods. Findings indicate that one female teacher with resource views about ELLs, who focused on what ELLs have and can do in her utterances, demonstrated shared production of knowledge in the classroom. However, another female teacher with deficit views about ELLs, who emphasized what ELLs do not have and cannot do in her utterances, enunciated and embodied teacher-scripted classroom practices. The findings illuminate how critical it is for educators to have resource perspectives toward ELLs. Resource perspectives cause teachers to recognize and use in their instruction the linguistic and cultural resources that ELLs bring to the classroom and thus foster the positive identity construction and academic achievement of ELLs.
Humanizing and Linguistically Responsive Pedagogy
Authors: Magill Kevin Russel
Published: April 2019

This chapter examines the work of successful, self-identifying critical social studies teachers who demonstrated (or a desire to adopt) a humanizing pedagogy and linguistically responsive practice in support of their mainstream English language learning (ELL) students. The author proceeds by outlining some of the challenges ELLs face, some of the linguistic theories in their support, and how social studies disciplinary skills (inquiry and dialogue) can exist as a part of linguistically supportive social studies pedagogy. The teachers in this critical case study successfully incorporated supportive disciplinary, linguistically, and culturally responsive pedagogical approaches to social studies teaching. However, because the teachers had little linguistic training, the author argues they could have benefited from formally incorporating supportive language practices in their everyday pedagogies.
Factors That Determine B-School Selection
Authors: Pathak Deepti , Agnihotri Shalini
Published: April 2019

Education is about the moulding of young and unprepared minds. It is a process that incorporates enormous inputs and commitment on the part of all stakeholders involved: teachers, peers, parents, and society. The outcome of education is measured in terms of the status person has gained, wealth, physical comfort, standard of living, and social esteem. Higher education plays important role in shaping the future of a student. Management education is one the most popular courses at post-graduate level. Hence, this chapter is an attempt to understand the factors that a student looks for while selecting a B-school. Primary survey is done to understand the factors affecting students' decision in selecting a B-school. It is observed that teaching pedagogy, placements, faculty, specialization, and fees play important roles in a student's decision process.
Buoyancy Effects on Unsteady MHD Chemically Reacting and Rotating Fluid Flow Past a Plate in a Porous Medium
Authors: Sharma Ram Prakash , Raju M.C. , Makinde Oluwole Daniel , Reddy P.R. Krishna , Reddy P. Chandra
Published: April 2019

An unsteady magnetohydrodynamic natural convection transfer of mass and heat flow over a vertical porous sheet under the influence of thermal radiation and thermo-diffusion effect. The dimensionless governing equations are solved analytically by employing Laplace transform technique. The impact of various physical parameters on momentum, energy and concentration are discussed and analyzed with the aid of graphs. Furthermore, the numerical values for local Skin friction, Nusselt number and Sherwood number are noted and examined. Increasing the values of thermal diffusion results in increasing of the concentration, but it decreases with Schmidt number. Skin friction reduces for increasing values of thermo-diffusion are discussed with the help of tables.
Effects of Heat Transfer on Peristaltic Transport of a Bingham Fluid through an Inclined Tube with Different Wave Forms
Authors: Vaidya Hanumesh , Rajashekhar Choudhari , Manjunatha Gudekote , Prasad K.V.
Published: April 2019

The present study investigates the effects of slip and heat transfer on peristaltic mechanism of Bingham fluid in an inclined tube. The sinusoidal, multi-sinusoidal, triangular, square and trapezoidal wave forms are considered. The analysis has been carried out under the assumptions of long wavelength and small Reynold's number approximations. The closed-form solutions are obtained for velocity, plug flow velocity, pressure gradient, streamlines, and temperature. The numerical integration is employed to investigate the effects of pressure rise and frictional force. The influence of relevant parameters on physiological quantities of interest is analyzed and discussed through graphs. The study reveals that velocity and thermal slip have a decreasing effect on velocity and temperature. Further, it is noticed that the volume of trapped bolus increases for increasing values of velocity slip parameter.
MHD Mixed Convective Flow of Casson Nanofluid over a Slender Rotating Disk with Source/Sink and Partial Slip Effects
Authors: Prasad K.V. , Vaidya Hanumesh , Makinde Oluwole Daniel , Setty B. Srikantha
Published: April 2019

The prominence of present work is to investigate the axisymmetric mixed convective magnetohydrodynamic (MHD) flow of a Casson nanofluid over a stretching variable thickened rotating disk in the presence of heat source/sink and velocity slip surface boundary condition. Besides, thermal buoyancy and viscous dissipation effects are examined. Convective heat and zero nanoparticles mass flux conditions at the boundaries of the disk are implemented. Von Karman similarity transformation is employed to formulate highly nonlinear coupled ordinary differential equations and solved via Optimal Homotopy Analysis Method (OHAM). The computed numerical values are presented graphically to predict the features of the embedded parameters. A new method (slope of the linear regression) is used to analyze the computed data of Skin friction coefficient, Nusselt number and Sherwood number. It is found that the power law exponent parameter plays a dominant role within the velocity, thermal and concentration boundary layer regions. Further, the fluid flow is opposed due to the magnetic field and velocity slip results in a reduced velocity boundary layer.
The Quasi-Binary System CeCoC2-CeNiC2: Crystal Structure and Physical Properties
Authors: Michor Herwig , Schumer Alexander , Hembara Mykola , Kotur Bogdan , Levytskyy Volodymyr , Babizhetskyy Volodymyr
Published: April 2019

The crystal structure of phases in the pseudo-binary system CeCo1–хNiхC2 (x = 0, 0.33, 0.5, 0.67, 0.79, 0.80, 0.83, 1) was investigated by means of X-ray powder diffraction. Co richer solid solutions CeCo1–хNiхC2 (0≤ x ≤0.5) crystallize in the monoclinic CeCoC2-type structure; a = 5.3968(2) Å, b = 5.4013(3) Å, c = 7.4762(3) Å, β = 102.136(3)°, V = 213.06(3) Å3 for x = 0.5. Ni-rich CeNi1–yCoyC2 (0≤ y ≤0.2) are isotypic with the orthorhombic CeNiC2-type structure, a = 3.8486(2) Å, b = 4.5479(2) Å, c = 6.1531(3) Å, V = 107.70(1) Å3 for y = 0.2. In the intermediate region (0.5< x <0.79) both phases, CeCo0.21Ni0.79C2 and CeCo0.5Ni0.5C2, coexist. The non-isoelectronic substitution of Ni by Co in solid solutions CeNi1–yCoyC2 causes a continuous reduction of the Néel temperature and finally, for CeCoC2, results in a paramagnetic Kondo-lattice ground state.
The Spin-Disorder Resistivity: The Disordered Local Moment Approach
Authors: Kudrnovsky J. , Drchal Vaclav , Turek Ilja , Wagenknecht David , Khmelevskyi Sergii
Published: April 2019

The spin-disorder resistivity (SDR) of a broad range of magneticmaterials, both ordered and disordered, is reviewed.We identify the SDR at the critical temperature with the residualresistivity of the corresponding system evaluated in the frameworkof the disordered local moment (DLM) model.The underlying electronic structure is determined in the frameworkof the tight-binding linear muffin-tin orbital method which employsthe coherent potential approximation to describe the DLM stateand chemical disorder.The DLM fixed-spin moment method is used in the case when the DLMmoment collapses.The Kubo-Greenwood approach is employed to estimate the resistivityof the DLM state.Formalism is applied to Fe and Ni and its alloys, Heusler alloys,and ordered ferromagnetic and antiferromagnetic alloys.Finally, the SDR of the Earth's core will be studied using thesame formalism.Calculations are compared with available experimental data.
Longitudinal Spin Fluctuations and Magnetic Ordering Temperature in Metals: First-Principle Modeling and Phase Space Integration Measure
Authors: Khmelevskyi Sergii
Published: April 2019

In magnetically ordered metals the magnitude of the local atomic moment become temperature dependent. To deal with this problem on the ab-initio level one need to employ a specific methodology for calculation of the electronic structure that takes into the account the magnetic disorder effects. In addition one needs to setup a special statistical models allowing simultaneously for ab-initio mapping and for the variation of the local spin magnitude. To this end here we discuss and employ methodology that is based on the Disordered Local Moment (DLM) formalism, spin-constraint Local Spin Density Approximation (LSDA) and Lichtenstein theorem for calculation of the inter-site exchange interactions. An extended classical Heisenberg Hamiltonian used for mapping allows for the variation of the lattice site spin magnitude. We consider here three representative canonical transition metals ferromagnets hcp Gd, bcc Fe and fcc Ni with quite a different character of the magnetic moment localization and illustrate the relative importance of the longitudinal spin fluctuations and the magnetic disorder induced electronic structure reconstruction. We use recently introduced linear measure [1] for integration over the longitudinal spin component in the classical configurational spin space.
Magnetic Phase Transition in MnSi Based on the First Principle Calculations of Electronic Structure and Spin Fluctuation Theory
Authors: Povzner Aleksandr , Nogovitsyna Tatyana A. , Volkov Arkadij G. , Nuretdinov Tagir
Published: April 2019

Based on the spin-fluctuation theory and LSDA + U + SO-calculations of the electronic structure, the spin states arising in the region of the magnetic phase transition in the helicoidal ferromagnet MnSi are studied. Within the framework of the stated model of the electronic structure, a temperature dependence of the homogeneous magnetic susceptibility is obtained near the temperature of the magnetic phase transition, which is in good agreement with experiment. At the temperature of the transition to the paramagnetic state, the left chirality vanishes, and spin correlations arise with a radius equal to the length of the spin helix, which then decreases with temperature. The results were obtained within the framework of the assignment of the Ministry of Education and Science of the Russian Federation, contract 3.9521.2017 / 8.9
The Ternary Systems {Sc, Ti}-Cu-Al at 800°C
Authors: Klymentiy Nastasia , Pukas Svitlana , Kuzhel Bohdan , Gladyshevskii Roman E.
Published: April 2019

The isothermal section at 800°C of the phase diagram of the ternary system Sc–Cu–Al was constructed in the whole concentration range using X-ray powder diffraction data. The existence of eight ternary compounds was confirmed: ScCu4.9‑6.0Al7.1‑6.0 (structure type ThMn12, Pearson symbol tI26, space group I4/mmm), Sc6Cu24.1Al11.9 (own structure type, cI176, Im-3), Sc2Cu6.25Al4.75 (own structure type, oS108, Cmmm), Sc3Cu7.5Al7.5 (Sc3Ni11Ge4, hP38, P63/mmc), ScCu2Al (MnCu2Al, cF16, Fm-3m), ScCu0.8Al0.2 (CsCl, cP2, Pm-3m), ScCu0.6Al1.4 (MgNi2, hP24, P63/mmc), and ScCuAl (MgZn2, hP12, P63/mmc), and the existence of a continuous solid solution ScCu1-xAlx (x = 0-1), based on the binary compounds ScCu and ScAl with CsCl-type structure (cP2, Pm-3m), was established. The investigation of the Ti–Cu–Al system at 800°C confirmed the existence of four ternary compounds: TiCu0.25Al2.75 (ZrAl3, tI16, I4/mmm), TiCu0.3-0.6Al2.7-2.4 (Cu3Au, cP4, Pm-3m), TiCu2-2.7Al1-0.3 (MnCu2Al, cF16, Fm-3m), and TiCu0.54-1.16All.46-0.84 (MgZn2, hP12, P63/mmc). Electrical resistivity measurements were performed for three compounds in the Sc–Cu–Al system and confirmed metal behavior in the temperature range 5-290 K.
Crystal Structure of the Dy3Ni11.83Si3.98 Compound
Authors: Belan Bohdana , Manyako Mykola , Pasinska Katarzyna , Demchyna Marta , Gladyshevskii Roman E.
Published: April 2019

The new ternary silicide Dy3Ni11.83(1)Si3.98(1)was synthesized from the elements by arc-melting and its crystal structure was determined by X-ray single-crystal diffraction. The compound crystallizes in a Sc3Ni11Ge4-type structure: Pearson symbolhP38, space groupP63/mmc(No. 194),a= 8.1990(7),c= 8.6840(7) Å,Z= 2;R= 0.0222, wR= 0.0284 for 365 reflections. The structure belongs to a large family of structures related to the EuMg5.2type, with representatives among ternary aluminides, silicides, germanides,etc.
Formation, Stability and Magnetism of New Gd3TAl3Ge2 Quaternary Compounds (T = Mn, Cu)
Authors: Kashyap Manish K. , Hackett Timothy A. , Provino Alessia , Pathak Arjun K. , Pecharsky Vitalij K. , Manfrinetti Pietro
Published: April 2019

A study on the formation and stability of new quaternary compounds with the general chemical formula Gd3TAl3Ge2(T = Mn, Cu) has been undertaken by experimental investigations (SEM-EDX, DTA and XRD) and density functional theory (DFT) calculations. These compounds crystallize in the hexagonal Y3NiAl3Ge2-type structure (hP9, P–62m, Z = 1) (an ordered, quaternary derivative of the ternary ZrNiAl or of the binary Fe2P prototypes), with lattice parameters values a = 7.0239(2) Å and c = 4.2580(1) Å for Gd3MnAl3Ge2and a = 7.0434(1) Å and c = 4.2089(1) Å for Gd3CuAl3Ge2. DTA suggests a peritectic reaction for the formation of these compounds (at 1245°C for Gd3CuAl3Ge2). The existence and stability of these phases has been explained on the basis of DFT calculations, and a comparison of ground state properties of the studied compounds with the earlier known Gd3CoAl3Ge2phase is outlined. The negative formation energies in all three cases govern the stability of compounds from theory as well, predicting Gd3MnAl3Ge2as the most stable phase with highest formation energy (–13.01 eV/f.u.). The total DOS are generic in nature and suggest the robust magnetism, with the Gd-f moments of ≈7 μB. An antiparallel coupling among Gd-f and T-d states is observed for all compounds, as usually seen in rare earth (R) - transition metal (T) compounds. Preliminary magnetization measurements on Gd3MnAl3Ge2show two ferromagnetic/ferrimagnetic (FM/FIM) like transitions at TC1= 142 K and TC2= 97 K, with another anomaly seen at ≈15 K. Isothermal magnetization data show no hysteresis even at 5 K, and the magnetization does not saturate up to 50 kOe, further suggesting a possible FIM behavior.
Deletion of Biliverdin Reductase A in Myeloid Cells Promotes Chemokine Expression and Chemotaxis in Part via a Complement C5a­–C5aR1 Pathway
Authors: Bisht Kavita , Canesin Giacomo , Cheytan Tasneem , Li Mailin , Nemeth Zsuzsanna , Csizmadia Eva , Woodruff Trent M. , Stec David E. , Bulmer Andrew C. , Otterbein Leo E. , Wegiel Barbara
Published: April 2019

Biliverdin reductase (BVR)-A is a pleotropic enzyme converting biliverdin to bilirubin and a signaling molecule that has cytoprotective and immunomodulatory effects. We recently showed that biliverdin inhibits the expression of complement activation fragment 5a receptor one (C5aR1) in RAW 264.7 macrophages. In this study, we investigated the role of BVR-A in determining macrophage inflammatory phenotype and function via regulation of C5aR1. We assessed expression of C5aR1, M1-like macrophage markers, including chemokines (RANTES, IP-10), as well as chemotaxis in response to LPS and C5a in bone marrow–derived macrophages from BVRfl/fl and LysM-Cre:BVRfl/fl mice (conditional deletion of BVR-A in myeloid cells). In response to LPS, macrophages isolated from LysM-Cre:BVRfl/fl showed significantly elevated levels of C5aR1 as well as chemokines (RANTES, IP10) but not proinflammatory markers, such as iNOS and TNF. An increase in C5aR1 expression was also observed in peritoneal macrophages and several tissues from LysM-Cre:BVRfl/fl mice in a model of endotoxemia. In addition, knockdown of BVR-A resulted in enhanced macrophage chemotaxis toward C5a. Part of the effects of BVR-A deletion on chemotaxis and RANTES expression were blocked in the presence of a C5aR1 neutralizing Ab, confirming the role of C5a–C5aR1 signaling in mediating the effects of BVR. In summary, BVR-A plays an important role in regulating macrophage chemotaxis in response to C5a via modulation of C5aR1 expression. In addition, macrophages lacking BVR-A are characterized by the expression of M1 polarization–associated chemokines, the levels of which depend in part on C5aR1 signaling.
TLR2 Plays a Pivotal Role in Mediating Mucosal Serotonin Production in the Gut
Authors: Wang Huaqing , Kwon Yun Han , Dewan Varun , Vahedi Fatemeh , Syed Saad , Fontes Michelle E. , Ashkar Ali A. , Surette Michael G. , Khan Waliul I.
Published: April 2019

Serotonin (5-hydroxytryptamine [5-HT]) is a key enteric signaling molecule that mediates various physiological processes in the gut. Enterochromaffin (EC) cells in the mucosal layer of the gut are the main source of 5-HT in the body and are situated in close proximity to the gut microbiota. In this study, we identify a pivotal role of TLR2 in 5-HT production in the gut. Antibiotic treatment reduces EC cell numbers and 5-HT levels in naive C57BL/6 mice, which is associated with downregulation of TLR2 expression but not TLR1 or TLR4. TLR2-deficient (Tlr2−/−) and Myd88−/− mice express lower EC cell numbers and 5-HT levels, whereas treatment with TLR2/1 agonist upregulates 5-HT production in irradiated C57BL/6 mice, which are reconstituted with Tlr2−/− bone marrow cells, and in germ-free mice. Human EC cell line (BON-1 cells) release higher 5-HT upon TLR2/1 agonist via NF-κB pathway. Tlr2−/− mice and anti-TLR2 Ab–treated mice infected with enteric parasite, Trichuris muris, exhibited attenuated 5-HT production, compared with infected wild-type mice. Moreover, excretory-secretory products from T. muris induce higher 5-HT production in BON-1 cells via TLR2 in a dose-dependent manner, whereby the effect of excretory-secretory products is abrogated by TLR2 antagonist. These findings not only suggest an important role of TLR2 in mucosal 5-HT production in the gut by resident microbiota as well as by a nematode parasite but also provide, to our knowledge, novel information on the potential benefits of targeting TLR2 in various gut disorders that exhibit aberrant 5-HT signaling.
Utility and limitations of ejection fraction and of diastolic dysfunction in heart failure patients
Authors: Mureddu Gian Francesco , Faggiano Andrea
Published: April 2019

The echocardiographic evaluation of left ventricular (LV) systolic function, and especially of ejection fraction (EF) plays a central role in the diagnosis of heart failure (HF) due to its undisputed prognostic value. Limitations of EF are substantially: i) the variability and reproducibility of measurements, and ii) the load-dependence. Measurement of stroke volume, longitudinal function and myocardial strain can overcome the limitations of EF in assessing the contractile reserve of patients with HF and may help to define both the phenotype and prognosis of the disease. The recognition of diastolic dysfunction (mainly by echocardiography) is the pathophysiological basis to make diagnosis of HF with preserved ejection fraction (HFpEF). The limitations are essentially related to its feasibility, since performing a multi-parametric quantitative echocardiographic evaluation, as indicated by the guidelines, may be difficult in clinical practice. Difficulties in method standardization, the poor attitude of cardiologists to test their reproducibility (test-retest, variability) favor the evaluation “at-a-glance” of LV structural and functional LV abnormalities.