bluuebunny/crossref_metadata_2025 huggingface dataset:
ZENS. IV. SIMILAR MORPHOLOGICAL CHANGES ASSOCIATED WITH MASS QUENCHING AND ENVIRONMENT QUENCHING AND THE RELATIVE IMPORTANCE OF BULGE GROWTH VERSUS THE FADING OF DISKS*
Authors: Carollo C. M. , Cibinel A. , Lilly S. J. , Pipino A. , Bonoli S. , Finoguenov A. , Miniati F. , Norberg P. , Silverman J. D.
Published: February 2016

We use the low-redshift Zurich Environmental Study (ZENS) catalog to study the dependence of the quenched satellite fraction at

, and of the morphological mix of these quenched satellites, on three different environmental parameters: group halo mass, halo-centric distance, and large-scale structure (LSS) overdensity. Within the two mass bins into which we divide our galaxy sample, the fraction of quenched satellites is more or less independent of halo mass and the surrounding LSS overdensity, but it increases toward the centers of the halos, as found in previous studies. The morphological mix of these quenched satellites is, however, constant with radial position in the halo, indicating that the well-known morphology–density relation results from the increasing fraction of quenched galaxies toward the centers of halos. If the radial variation in the quenched fraction reflects the action of two quenching processes, one related to mass and the other to environment, then the constancy with radius of the morphological outcome suggests that both have the same effect on the morphologies of the galaxies. Alternatively, mass and environment quenching may be two reflections of a single physical mechanism. The quenched satellites have larger bulge-to-total ratios (B/T) and smaller half-light radii than the star-forming satellites. The bulges in quenched satellites have very similar luminosities and surface brightness profiles, and any mass growth of the bulges associated with quenching cannot greatly change these quantities. The differences in the light-defined B/T and in the galaxy half-light radii are mostly due to differences in the disks, which have lower luminosities in the quenched galaxies. The difference in galaxy half-light radii between quenched and star-forming satellites is however larger than can be explained by uniformly fading the disks following quenching, and the quenched disks have smaller scale lengths than in star-forming satellites. This can be explained either by a differential fading of the disks with galaxy radius or the disks being generally smaller in the past, both of which would be expected in an inside-out disk growth scenario. The overall conclusion is that, at least at low redshifts, the structure of massive quenched satellites at these masses is produced by processes that operate before the quenching takes place. A comparison of our results with semianalytic models argues for a reduction in the efficiency of group halos in quenching their disk satellites and for mechanisms to increase the B/T of low-mass quenched satellites.
CRYSTAL CHEMISTRY OF THREE-COMPONENT WHITE DWARFS AND NEUTRON STAR CRUSTS: PHASE STABILITY, PHASE STRATIFICATION, AND PHYSICAL PROPERTIES
Authors: Engstrom T. A. , Yoder N. C. , Crespi V. H.
Published: February 2016

A systematic search for multicomponent crystal structures is carried out for five different ternary systems of nuclei in a polarizable background of electrons, representative of accreted neutron star crusts and some white dwarfs. Candidate structures are “bred” by a genetic algorithm and optimized at constant pressure under the assumption of linear response (Thomas–Fermi) charge screening. Subsequent phase equilibria calculations reveal eight distinct crystal structures in the T = 0 bulk phase diagrams, five of which are complicated multinary structures not previously predicted in the context of compact object astrophysics. Frequent instances of geometrically similar but compositionally distinct phases give insight into structural preferences of systems with pairwise Yukawa interactions, including and extending to the regime of low-density colloidal suspensions made in a laboratory. As an application of these main results, we self-consistently couple the phase stability problem to the equations for a self-gravitating, hydrostatically stable white dwarf, with fixed overall composition. To our knowledge, this is the first attempt to incorporate complex multinary phases into the equilibrium phase-layering diagram and mass–radius-composition dependence, both of which are reported for He–C–O and C–O–Ne white dwarfs. Finite thickness interfacial phases (“interphases”) show up at the boundaries between single-component body-centered cubic (bcc) crystalline regions, some of which have lower lattice symmetry than cubic. A second application—quasi-static settling of heavy nuclei in white dwarfs—builds on our equilibrium phase-layering method. Tests of this nonequilibrium method reveal extra phases that play the role of transient host phases for the settling species.
BULGE-DRIVEN FUELING OF SEED BLACK HOLES
Authors: Park KwangHo , Ricotti Massimo , Natarajan Priyamvada , Bogdanović Tamara , Wise John H.
Published: February 2016

We examine radiation-regulated accretion onto intermediate-mass and massive black holes (BHs) embedded in a bulge component. Using spherically symmetric one-dimensional radiation-hydrodynamics simulations, we track the growth of BHs accreting from a cold, neutral gas reservoir with temperature

K. We find that the accretion rate of BHs embedded in bulges is proportional to

, where r
B,eff is the increased effective Bondi radius that includes the gravitational potential of the bulge, and r
B is the Bondi radius of the BH. The radiative feedback from the BH suppresses the cold accretion rate to ∼1% of the Bondi rate when a bulge is not considered. However, we find that the BH fueling rate increases rapidly when the bulge mass M
bulge is greater than the critical value of ∼106
M
☉ and is proportional to

, where

is the BH mass. Since the critical bulge mass is independent of the central BH mass, the growth rate of BHs with masses

, 104, and 106
M
☉ exhibits distinct dependencies on the bulge-to-BH mass ratio. Our results imply that light seed BHs (≲102
M
☉), which might be the remnants of the Pop III stars, cannot grow through accretion coevally with the early assembly of the bulge of the host galaxies until the bulge reaches the critical mass. However, massive BH seeds (≳105
M
☉), which may form via direct collapse, are more likely to be embedded in a supercritical bulge, and thus can grow efficiently coupling to the host galaxies and driving the early evolution of the M
BH–σ relationship.
CONSTRAINTS ON HYBRID METRIC-PALATINI GRAVITY FROM BACKGROUND EVOLUTION
Authors: Lima N. A. , S.-Barreto V.
Published: February 2016

In this work, we introduce two models of the hybrid metric-Palatini theory of gravitation. We explore their background evolution, showing explicitly that one recovers standard General Relativity with an effective cosmological constant at late times. This happens because the Palatini Ricci scalar evolves toward and asymptotically settles at the minimum of its effective potential during cosmological evolution. We then use a combination of cosmic microwave background, supernovae, and baryonic accoustic oscillations background data to constrain the models’ free parameters. For both models, we are able to constrain the maximum deviation from the gravitational constant G one can have at early times to be around 1%.
LOWER BOUND ON THE COSMIC TeV GAMMA-RAY BACKGROUND RADIATION
Authors: Inoue Yoshiyuki , Tanaka Yasuyuki T.
Published: February 2016

The Fermi gamma-ray space telescope has revolutionized our understanding of the cosmic gamma-ray background radiation in the GeV band. However, investigation on the cosmic TeV gamma-ray background radiation still remains sparse. Here, we report the lower bound on the cosmic TeV gamma-ray background spectrum placed by the cumulative flux of individual detected extragalactic TeV sources including blazars, radio galaxies, and starburst galaxies. The current limit on the cosmic TeV gamma-ray background above 0.1 TeV is obtained as 2.8 × 10−8(E/100 GeV)−0.55 exp(−E/2100GeV)[GeV cm−2 s−1 sr−1] < E
2
dN/dE < 1.1 × 10−7(E/100 GeV)−0.49 [GeV cm−2 s−1 sr−1], where the upper bound is set by requirement that the cascade flux from the cosmic TeV gamma-ray background radiation can not exceed the measured cosmic GeV gamma-ray background spectrum. Two nearby blazars, Mrk 421 and Mrk 501, explain ∼70% of the cumulative background flux at 0.8–4 TeV, while extreme blazars start to dominate at higher energies. We also provide the cumulative background flux from each population, i.e., blazars, radio galaxies, and starburst galaxies which will be the minimum requirement for their contribution to the cosmic TeV gamma-ray background radiation.
A NEW MULTI-ENERGY NEUTRINO RADIATION-HYDRODYNAMICS CODE IN FULL GENERAL RELATIVITY AND ITS APPLICATION TO THE GRAVITATIONAL COLLAPSE OF MASSIVE STARS
Authors: Kuroda Takami , Takiwaki Tomoya , Kotake Kei
Published: February 2016

We present a new multi-dimensional radiation-hydrodynamics code for massive stellar core-collapse in full general relativity (GR). Employing an M1 analytical closure scheme, we solve spectral neutrino transport of the radiation energy and momentum based on a truncated moment formalism. Regarding neutrino opacities, we take into account a baseline set in state-of-the-art simulations, in which inelastic neutrino–electron scattering, thermal neutrino production via pair annihilation, and nucleon–nucleon bremsstrahlung are included. While the Einstein field equations and the spatial advection terms in the radiation-hydrodynamics equations are evolved explicitly, the source terms due to neutrino–matter interactions and energy shift in the radiation moment equations are integrated implicitly by an iteration method. To verify our code, we first perform a series of standard radiation tests with analytical solutions that include the check of gravitational redshift and Doppler shift. A good agreement in these tests supports the reliability of the GR multi-energy neutrino transport scheme. We then conduct several test simulations of core-collapse, bounce, and shock stall of a 15

star in the Cartesian coordinates and make a detailed comparison with published results. Our code performs quite well to reproduce the results of full Boltzmann neutrino transport especially before bounce. In the postbounce phase, our code basically performs well, however, there are several differences that are most likely to come from the insufficient spatial resolution in our current 3D-GR models. For clarifying the resolution dependence and extending the code comparison in the late postbounce phase, we discuss that next-generation Exaflops class supercomputers are needed at least.
SEMI-ANALYTIC GALAXY EVOLUTION (SAGE): MODEL CALIBRATION AND BASIC RESULTS
Authors: Croton Darren J. , Stevens Adam R. H. , Tonini Chiara , Garel Thibault , Bernyk Maksym , Bibiano Antonio , Hodkinson Luke , Mutch Simon J. , Poole Gregory B. , Shattow Genevieve M.
Published: February 2016

This paper describes a new publicly available codebase for modeling galaxy formation in a cosmological context, the “Semi-Analytic Galaxy Evolution” model, or sage for short.5
sage is a significant update to the 2006 model of Croton et al. and has been rebuilt to be modular and customizable. The model will run on any N-body simulation whose trees are organized in a supported format and contain a minimum set of basic halo properties. In this work, we present the baryonic prescriptions implemented in sage to describe the formation and evolution of galaxies, and their calibration for three N-body simulations: Millennium, Bolshoi, and GiggleZ. Updated physics include the following: gas accretion, ejection due to feedback, and reincorporation via the galactic fountain; a new gas cooling–radio mode active galactic nucleus (AGN) heating cycle; AGN feedback in the quasar mode; a new treatment of gas in satellite galaxies; and galaxy mergers, disruption, and the build-up of intra-cluster stars. Throughout, we show the results of a common default parameterization on each simulation, with a focus on the local galaxy population.
THE GAS MASS OF STAR-FORMING GALAXIES AT z ≈ 1.3
Authors: Kanekar Nissim , Sethi Shiv , Dwarakanath K. S.
Published: February 2016

We report a Giant Metrewave Radio Telescope search for H i 21 cm emission from a large sample of massive star-forming galaxies at z ≈ 1.18–1.34, lying in sub-fields of the DEEP2 Redshift Survey. The search was carried out by co-adding (“stacking”) the H i 21 cm emission spectra of 857 galaxies, after shifting each galaxy’s H i 21 cm spectrum to its rest frame. We obtain the 3σ upper limit S
H i
 < 2.5 μJy on the average H i 21 cm flux density of the 857 galaxies, at a velocity resolution of ≈315 km s−1. This yields the 3σ constraint

on the average H i mass of the 857 stacked galaxies, the first direct constraint on the atomic gas mass of galaxies at z > 1. The implied limit on the average atomic gas mass fraction (relative to stars) is M
GAS/M
* < 0.5, comparable to the cold molecular gas mass fraction in similar star-forming galaxies at these redshifts. We find that the cosmological mass density of neutral atomic gas in massive star-forming galaxies at z ≈ 1.3 is ΩGAS < 3.7 × 10−4, significantly lower than ΩGAS estimates in both galaxies in the local universe and damped Lyα absorbers at z ≥ 2.2. Massive blue star-forming galaxies thus do not appear to dominate the neutral atomic gas content of the universe at z ≈ 1.3.
AN ULTRAVIOLET SPECTRUM OF THE TIDAL DISRUPTION FLARE ASASSN-14li
Authors: Cenko S. Bradley , Cucchiara Antonino , Roth Nathaniel , Veilleux Sylvain , Prochaska J. Xavier , Yan Lin , Guillochon James , Maksym W. Peter , Arcavi Iair , Butler Nathaniel R. , Filippenko Alexei V. , Fruchter Andrew S. , Gezari Suvi , Kasen Daniel , Levan Andrew J. , Miller Jon M. , Pasham Dheeraj R. , Ramirez-Ruiz Enrico , Strubbe Linda E. , Tanvir Nial R. , Tombesi Francesco
Published: February 2016

We present a Hubble Space Telescope Space Telescope Imaging Spectrograph spectrum of ASASSN-14li, the first rest-frame ultraviolet (UV) spectrum of a tidal disruption flare (TDF). The underlying continuum is well fit by a blackbody with

K, an order of magnitude smaller than the temperature inferred from X-ray spectra (and significantly more precise than previous efforts based on optical and near-UV photometry). Superimposed on this blue continuum, we detect three classes of features: narrow absorption from the Milky Way (probably a high-velocity cloud), and narrow absorption and broad (∼2000–8000 km s−1) emission lines at or near the systemic host velocity. The absorption lines are blueshifted with respect to the emission lines by Δv =  −(250–400) km s−1. Due both to this velocity offset and the lack of common low-ionization features (Mg ii, Fe ii), we argue these arise from the same absorbing material responsible for the low-velocity outflow discovered at X-ray wavelengths. The broad nuclear emission lines display a remarkable abundance pattern: N iii], N iv], and He ii are quite prominent, while the common quasar emission lines of C iii] and Mg ii are weak or entirely absent. Detailed modeling of this spectrum will help elucidate fundamental questions regarding the nature of the emission processes at work in TDFs, while future UV spectroscopy of ASASSN-14li would help to confirm (or refute) the previously proposed connection between TDFs and “N-rich” quasars.
A SEARCH FOR BRIEF OPTICAL FLASHES ASSOCIATED WITH THE SETI TARGET KIC 8462852
Authors: Abeysekara A. U. , Archambault S. , Archer A. , Benbow W. , Bird R. , Buchovecky M. , Buckley J. H. , Byrum K. , Cardenzana J. V , Cerruti M. , Chen X. , Christiansen J. L. , Ciupik L. , Cui W. , Dickinson H. J. , Eisch J. D. , Errando M. , Falcone A. , Fegan D. J. , Feng Q. , Finley J. P. , Fleischhack H. , Fortin P. , Fortson L. , Furniss A. , Gillanders G. H. , Griffin S. , Grube J. , Gyuk G. , Hütten M. , Håkansson N. , Hanna D. , Holder J. , Humensky T. B. , Johnson C. A. , Kaaret P. , Kar P. , Kelley-Hoskins N. , Kertzman M. , Kieda D. , Krause M. , Krennrich F. , Kumar S. , Lang M. J. , Lin T. T. Y. , Maier G. , McArthur S. , McCann A. , Meagher K. , Moriarty P. , Mukherjee R. , Nieto D. , O’Brien S. , Bhróithe A. O’Faoláin de , Ong R. A. , Otte A. N. , Park N. , Perkins J. S. , Petrashyk A. , Pohl M. , Popkow A. , Pueschel E. , Quinn J. , Ragan K. , Ratliff G. , Reynolds P. T. , Richards G. T. , Roache E. , Santander M. , Sembroski G. H. , Shahinyan K. , Staszak D. , Telezhinsky I. , Tucci J. V. , Tyler J. , Vincent S. , Wakely S. P. , Weiner O. M. , Weinstein A. , Williams D. A. , Zitzer B.
Published: February 2016

The F-type star KIC 8462852 has recently been identified as an exceptional target for search for extraterrestrial intelligence (SETI) observations. We describe an analysis methodology for optical SETI, which we have used to analyze nine hours of serendipitous archival observations of KIC 8462852 made with the VERITAS gamma-ray observatory between 2009 and 2015. No evidence of pulsed optical beacons, above a pulse intensity at the Earth of approximately

, is found. We also discuss the potential use of imaging atmospheric Cherenkov telescope arrays in searching for extremely short duration optical transients in general.
On-Treatment HCV RNA in Patients with Varying Degrees of Fibrosis and Cirrhosis in the SOLAR-1 Trial
Authors: Welzel Tania M , Reddy K Rajender , Flamm Steven L , Denning Jill , Lin Ming , Hyland Rob , Pang Phillip S , McHutchison John G , Charlton Michael , Everson Gregory T , Zeuzem Stefan , Afdhal Nezam
Published: February 2016

Background

In the Phase II SOLAR-1 study, 12 or 24 weeks of ledipasvir/sofosbuvir and ribavirin yielded high sustained virological response rates at 12 weeks (SVR12) in patients with chronic HCV infection and advanced liver disease, including untransplanted patients with decompensated cirrhosis and liver transplant recipients with all stages of liver disease.

Methods

We performed a post hoc analysis using data from this study to investigate associations between baseline characteristics and early on-treatment HCV RNA, and to determine the utility of early virological response (week 2 and 4) to predict SVR12. Serum HCV RNA was quantified using the Roche COBAS® Ampliprep®/Cobas TaqMan HCV Test, Version 2.0 with a lower limit of quantification (LLOQ) of 15 IU/ml.

Results

Most patients achieved HCV RNA ≤LLOQ by treatment week 4 and target not detected (TND) by week 6. Baseline factors significantly associated with HCV RNA ≤LLOQ at week 2 were low HCV RNA (≤800,000 IU/ml), absence of cirrhosis, age ≤60 years and no prior treatment experience. At week 4, low HCV RNA, absence of cirrhosis and IL28B CC were associated with ≤LLOQ, TND. No baseline factors were associated with week 6 response. There was no association between early on-treatment HCV RNA and SVR12.

Conclusions

On-treatment HCV RNA quantification is of limited clinical use in patients with advanced liver disease and/or liver transplantation and does not predict SVR12. ClinicalTrials.gov: NCT01938430.
Refractory Epilepsy-MRI, EEG and CT scan, a Correlative Clinical Study
Authors: Nikodijevic Dijana , Banevaâ€“Dolnenec Natalija , Petrovska-Cvetkovska Dragana , Caparoska Daniela
Published: February 2016

OBJECTIVES: Refractory epilepsies (RE), as well as, the surgically correctable syndromes, are of great interest, since they affect the very young population of children and adolescents. The early diagnosis and treatment are very important in preventing the psychosocial disability. Therefore MRI and EEG are highly sensitive methods in the diagnosis and localization of epileptogenic focus, but also in pre-surgical evaluation of these patients. The aim of our study is to correlate the imaging findings of EEG, MRI and CT scan in refractory symptomatic epilepsies, and to determine their specificity in detecting the epileptogenic focus.METHODS: The study was prospective with duration of over two years, open-labelled, and involved a group of 37 patients that had been evaluated and diagnosed as refractory epilepsy patients. In the evaluation the type and frequency of seizures were considered, together with the etiologic factors and their association, and finally the risk for developing refractory epilepsy was weighted. EEG and MRI findings and CT scan results were evaluated for their specificity and sensitivity in detecting the epileptogenic focus, and the correlation between them was analyzed.RESULTS: Regarding the type of seizures considered in our study, the patients with PCS (partial complex seizures) dominated, as opposed to those with generalized seizures (GS) (D=1.178, p < 0.05). Positive MRI findings were registered in 28 patients (75.7%). Most of them were patients with hippocampal sclerosis, 12 (42.8%), and also they were found to have the highest risk of developing refractory epilepsy (RE) (Odds ratio = 5.7), and the highest association between the etiologic factor and refractory epilepsy (p < 0.01). In detecting the epileptogenic focus, a significant difference was found (p < 0.01) between MRI and CT scan findings, especially in patients with hippocampal sclerosis and cerebral malformations. There was a strong correlation between the MRI findings and the etiologic factor (R = 1), and for CT scan and etiologic factor an R=0.75 correlation. There was a significant difference between imaging methods MRI/CT (p < 0.1), and CT/EEG (p < 0.05) in detecting the etiologic factor, and little difference was noticed between findings of EEG/MRI.CONCLUSION: Our study confirms that for an accurate diagnosis of refractory epilepsy in patients, a combination of neuroimaging and neurophysiologic methods is required. MRI showed to be highly sensitive in detecting the etiologic factor in RE patients, whereas EEG was sensitive in localization of the epileptogenic focus, with high correlation between these two methods. An early diagnosis of these patients is very important in having a better therapeutic response and prognosis for them.
Industrial restructuring and downsizing: Case study of Central Croatia
Authors: Lončar Jelena , Braičić Zdenko
Published: February 2016

The collapse of socialist economic system in Croatia was followed by a period of economic transition during which the industry sector was affected by major changes. This study, on an example of Central Croatia, analyzes the spatial aspect of these changes between 1990 and 2011. The used data were taken from the National Bureau of Statistics and studies in which the transition period industry is researched from economic and geographical point of view. Calculations of most indicators referred to a county level while some indicators were calculated at the level of administrative cities and municipalities. It was found that, in Central Croatia, there had come to a process of deindustrialization, and in some rare cases a process of reindustrialization, an increase in importance of tertiary and quaternary activities, and calculation of some indicators such as degree of industrialization, location quotient, regional factor and index of specialization indicated on the existence of significant differences between individual parts of Central Croatia.
Bojan Erhartič's contribution to geography
Authors: Smrekar Aleš , Zorn Matija , Komac Blaž
Published: February 2016

At the beginning of the twenty-first century, Bojan Erhartič had a strong impact on Slovenian geography because he placed it on the map of countries where geographers deal with geomorphological heritage. He began his research path into the world of natural heritage with the study of geography. After receiving his bachelor’s degree, he turned his attention to studying geodiversity, and this led him to issues concerning the evaluation of geomorphological heritage, especially in mountainous areas. Erhartič was among the first in Slovenian geography to deal with the aesthetic evaluation of geomorphological heritage. His interest in the “beauty of nature” stemmed from many years of planned work in (geographical) photography. The Anton Melik Geographical Institute of the Research Center of the Slovenian Academy of Sciences and Arts holds approximately 218,000 of his “geographical” photos, which he took during his many travels in more than forty countries on five continents.
Quantitative analysis of marginalization indicators – example of the peninsula of Pelješac, Croatia
Authors: Šiljeg Silvija , Šiljeg Ante , Glamuzina Nikola
Published: February 2016

Besides marginalization on the international, national and regional levels, it is possible to speak about marginalization on the local level. It is especially important since its consequences and various aspects are felt in everyday life. This paper presents the results of quantitative analysis of the process of marginalization on the local level on the example of the peninsula of Pelješac in Croatian Littoral. The main aim of the research is to contribute to propose a quantitative approach in the research of marginalization. The authors have defined four indicators which form the basis of the GIS analysis: demographic, socio-economic, educational and an indicator of physical marginalization. In order to see relationship between the indicators, the peninsula has been divided into zones which differ according to the marginalization process. Such differences are expressed quantitatively in form of an index of marginalization.
Spatial diversity of tourist function development: the municipalities of Poland’s West Pomerania province
Authors: Borzyszkowski Jacek , Marczak Mirosław , Zarębski Patrycjusz
Published: February 2016

This article examines the spatial diversity of tourist function development using the example of one of Poland’s sixteen main administrative regions: the West Pomerania Province (Polish: Województwo zachodniopomorskie). The analysis was carried out based on the values of the Defert tourist function index, which is one of the basic indexes used in tourism geography. The analysis demonstrated significant differences between the individual municipalities in the region examined. This confirms the assumption that seaside municipalities have the highest tourist function development.
Transferability of a predictive Robinia pseudacacia distribution model in northeast Slovenia
Authors: Ribeiro Daniela , Somodi Imelda , Čarni Andraž
Published: February 2016

The main goal of this study is to assess the transferability of a species distribution model (SDM) for Robinia pseudacacia (black locust) to two testing sites in the Prekmurje region in northeast Slovenia. The predictive performance of the SDM at the testing sites was measured by 1) visual evaluation, 2) confusion matrix, 3) true positive rate (TPR), 4) the maximum of the true skill statistics (TSS) over possible cutoffs, and 5) paired-sample ANOVA. We show that the model adequately predicted potential distribution of the species in the region, which ensures that extension of the prediction at this scale will be a reliable base for nature conservation decisions. This also serves as a positive example for within-region transfer and extension of SDMs.
Routes et antiroutes de l’immigration tamoule sri-lankaise
Authors: Goreau-Ponceaud Anthony
Published: February 2016

Le Sri Lanka, île de l’océan indien de plus de 20 millions d’habitants, dont les trois-quarts ont pour langue maternelle le cinghalais (une langue issue du fonds indo-aryen) et le dernier quart le tamoul (langue dravidienne d’Inde du Sud)1, a été marqué pendant près de trois décennies par un conflit séparatiste sanglant, déclenché par des groupes militants appartenant à la minorité tamoule autochtone.
Transnational masculinity: Indian nurses’ husbands in Ireland
Authors: Percot Marie
Published: February 2016

I have met many young Christian men in Kerala whose ambition, like Philip’s, was to migrate by marrying a nurse. If the matrimonial market used to be harsh on nurses a few decades ago, the picture has changed and nurses are now on high demand. The stigma attached to this profession in India has certainly not completely vanished, but in Kerala, nursing has become a real chance to enhance one’s career opportunities. While visiting matrimonial websites (See for instance keralamatrimonials.com, keralamatrimony.com or shaadi.com), it is easy to check how much they are looked after by prospective grooms. However despised may the commonly named USA nurses be by the highest class/casts (George, 2005), they tend to represent the key to the Western dream for loads of young men belonging to the Christian Malayali middle class who don’t envisage the possibility of a bright future in their own country.
Bombardment Induced Ion Transport through Ion Conducting Glasses
Authors: Weitzel Karl Michael
Published: February 2016

The recently developed bombardment induced ion transport (BIIT) technique is reviewed. BIIT is based on shining an energy-selected alkali ion beam at the surface of a sample of interest. Attachment of these ions leads to the build-up of a surface potential and a surface particle density. This in turn generates the corresponding gradients which induce ion transport towards a single metal electrode connected to the backside of the sample where it is detected as a neutralization current. Two different versions of BIIT are presented, i.) the native ion BIIT and ii.) the foreign ion BIIT. The former is demonstrated to provide access to absolute ionic conductivities and activation energies, the latter leads to the generation of electrodiffusion profiles. Theoretical modelling of these concentration profiles by means of the Nernst-Planck-Poisson theory allows to deduce the concentration dependence of diffusion coefficients.
Interdiffusion in Ionic Compounds
Authors: Belova Irina V. , Murch Graeme E.
Published: February 2016

In this chapter, we review the Nernst-Planck equation describing the cation interdiffusion coefficient, the two tracer cation diffusion coefficients and the thermodynamic factor in ionic compounds and how it is related to the analogous Darken-Manning relationship in binary alloy systems. We make use of the Onsager flux equations of non-equilibrium thermodynamics to rigorously address the problem. The recently found correction factor to the Nernst-Planck equation is analyzed visually by means of computer simulation
Nanostructured Metal Films Formed onto Porous Silicon Template
Authors: Bandarenka Hanna , Dolgiy Alexei , Chubenko Eugene , Redko Sergei , Girel Kseniya , Prischepa Serghej L. , Panarin Andrei , Terekhov Sergei , Pilipenko Vladimir , Bondarenko Vitaly
Published: February 2016

The review reports on the results of our research work on nanostructured metal films onto porous silicon. Principal steps of the techniques allowing fabrication of metal films completely inheriting morphological pattern of different types of porous silicon are presented. It is shown, that giving of the nanostructured pattern to metal films by means of porous silicon template opens their new structural, optical, mechanical and electrical properties, which can be successfully applied in nanoelectronics and biomedicine, particularly including devices based on superconductivity effect, SERS analysis with picomolar sensitivity and transdermal drug delivery by electroporation.
Technological Modes of Stretching Operation Involving Wall Thinning of Axissymmetric Blanks Made out of Anisotropic Materials
Authors: Yakovlev Sergey Sergeevich , Gryazev Michail Vasilievich , Travin Vadim Yurievich
Published: February 2016

Provided is a mathematical model of stretching operation involving wall thinning of axisymmetric blanks of anisotropic materials. Obtained were correlations which can be used to evaluate the kinematics of the material flow, the stress and strain states of the blank, the force conditions and the limit possibilities of drawing involving wall thinning of thick-walled anisotropic axisymmetric blanks. Comparison of results of theoretical calculation against experimental data have shown satisfactory similarity. The maximal difference between the theoretical and experimental data does not exceed 10 percent. The research results were used in developing the technological process to manufacture thick-walled cylindrical blanks for critical axisymmetric items made of steel 11YUA.
The Wear-Resistance and Antifrictional Properties of Hard Alloys of Chromium Carbide with Titanium Produced by the Explosive Compaction of Powders
Authors: Krokhalev Aleksandr Vasilevich , Kharlamov V.O. , Tupitsin M.A. , Kuz’min S.V. , Lysak V.I.
Published: February 2016

The tribological characteristics of the Cr3С2–Ti system hard alloys produced by the explosive compaction of powders containing 20, 30, 40, and 50 vol. % of the titanium binder are investigated. The general approach to selecting the optimal structure and properties of wear-resistant hard alloys for manufacturing the slider bearing parts working in conjunction with silicified graphite under water lubrication conditions is formulated. It is shown that, to attain the highest antifriction characteristics and minimal wear of the friction unit, the alloy should have the maximally possible hardness with the minimally admissible specific volume of a carbide phase in the material structure. It is established that such alloys have higher antifriction characteristics and wear resistance than silicified graphite and the Cr3C2–20% Ni-type materials produced by conventional methods.
Pressing Tubes with Conical-Stepped Needles Computer Simulating
Authors: Grechnikov Fedor Vasilievich , Afanasyev Alexander Evgenievich , Kargin Vladimir Rodionovich , Kargin Boris Vladimirovich
Published: February 2016

There are the results of computer simulating using DEFORM-2D specialized software and experimental researches during the pressing of aluminium alloys tubes with conical-stepped needles. On the basis of the experiment mathematical planning and dividing coordinate grid the influence of the taper angle and needle position to the pressing stress and the intensity of deformation relative to the die parallel land was established. The optimal parameters determining methods of conical-stepped needles geometry were proposed.
Characteristics of Large Bars Extruding Using Small Extrusion Ratio
Authors: Kargin Vladimir Rodionovich , Deryabin Andrey Yurievich
Published: February 2016

Computer analysis of distribution of stress intensity and strain intensity in different cross sections of plastic deformation region and in finished material in the course of hot extruding process was carried out. By means of the finite element method in the Deform-2D program influence of small extrusion ratio value on stress-strained state of large 250mm to 500mm dia. bars in 7075 high-strength Aluminium alloy was established.
Determination of Rheological Properties of Titanium Alloys under Conditions of High Strain Rates
Authors: Balaykin Andrey V. , Kondratev Alexsandr I. , Galkina Natalia V.
Published: February 2016

This article considers the method of determining the parameters of the rheological properties of material of titanium alloy BT6 used in aircraft engine technology, under face milling. Calculations were carried out in CAE system Deform using FEM - model.
The Forming Process of the Sharply Curved Offsets by the Pushing Method
Authors: Maslov Valentin Dmitrievich , Popov I.P. , Misyura Valentin Dmitrievich
Published: February 2016

The scheme of device for the thin-walled sharply curved offset parts forming by pushing the tube-shaped workpiece through the die channel is presented. The numerical simulation of the bending process by pushing the tube-shaped workpiece is performed using ANSYS-LS/DYNA program complex. The wall thickness distribution law along the generatrix of curved workpiece is determined. The influence of curvature radius of the curved offset part on thinning deformation during bending process is defined. The experimental determination of the AISI 304 stainless steel tube-shaped workpiece thickness changes is performed. Application of the developed device for the sharply curved offset parts manufacturing according to DIN/ISO standards is demonstrated.
Forming of Small-Diameter Tubes via Pulse-Magnetic Technology
Authors: Chernikov Dmitrij
Published: February 2016

The article implies development of effective forming method of small-diameter tubular workpieces with the use of pulse-magnetic technologies. Results of LS-DYNA computational simulation of the process and experimental results are shown. Also, advantages of the method are shown and recomendations of it's use are given.
Nanostructured Aluminum Matrix Composites of Al-10%TiC Obtained In Situ by the SHS Method in the Melt
Authors: Amosov Aleksandr P. , Luts A.R. , Ermoshkin A.A.
Published: February 2016

The aim of this study was an investigation of the influence of technological parameters of the process of self-propagating high-temperature synthesis (SHS) on the formation of nanoparticles of titanium carbide from a mixture of powders of titanium and carbon in molten aluminum and on the properties of the obtained composite Al-10 wt. %TiC. The results show that the application of such techniques as the use of titanium powder of coarse fraction, the integrated flux of composition 30-35% NaCI, 52-57% KCI, 10-13% Na2SiF6 and adding aluminum powder to the initial charge can reduce the size of most of the synthesized particles of the carbide phase TiC to ultrafine sizes. At the same time, the replacement of 20% titanium metal powder in the charge with the titanium-containing salt Na2TiF6 makes it possible to synthesize nanoparticles of titanium carbide with size less than 0.1 μm in the composite Al-10%TiC. The produced SHS composite Al-10%TiC is characterized by a high level of physico-mechanical and tribological properties with good corrosion resistance. Reinforcement with ultrafine and nanosized particles of TiC enhances the strength characteristics of the composite Al-10%TiC by 2.5-2.9 times in comparison with pure aluminum, while the reinforcement with microsized particles of TiC (2-4 μm) only by 1.5-1.7 times; resistance to corrosion increases by 4-5 times.
Modeling the Hot Deformation Behavior of 1565ch Aluminum Alloy
Authors: Rushchits S.V. , Aryshensky E.V. , Sosedkov S.M. , Akhmed'yanov A.M.
Published: February 2016

The deformation behavior of 1565ch alloy under the plane-strain conditions in the temperature range of 350–490 оС and strain rates range of 0,1–10 s-1 is studied. The expression for steady flow stress as the functions of temperature of deformation and strain rate is obtained. It is established that 1565ch alloy with zirconium addition shows higher strain resistance and less tendency to dynamic and static recrystallization than AMg6.
Effect of Strain on the Anisotropy Coefficient of Sheet Alloys AA2024, Ti-2Al-1Mn, Titanium Grade 2, STEEL X10CrNiTi18-9
Authors: Nosova Ekaterina A. , Grechnikov Fedor Vasilievich
Published: February 2016

Anisotropy of the plastic properties is an index of sheet’s ability to stamping. In this work the transverse deformation coefficient and r-value were used. Uniaxial test was made for annealed pieces of 1 mm thickness from aluminum alloy AA2024, steel X10CrNiTi18-9, Titanium Grade 2 and titanium alloy Ti-2Al-1Mn. Pieces were cut at angle of 0, 22.5, 45, 67.5 and 90O to the rolling direction. Steel pieces have anisotropy coefficients practically independent from angle between it’s’ axis and the rolling direction. Pieces made of AA2024 cut at angle 45О to the rolling direction have largest anisotropy coefficients. Titanium alloys have the largest coefficients for angle 67,5О between axis of piece and the rolling direction. Both indexes of anisotropy are higher for titanium alloys, which is property of HCP-metals.
Manufacturing Process Optimization at Enterprises
Authors: Matveeva Е.A. , Simagina S.G.
Published: February 2016

The article deals with competitiveness ensuring of enterprises at the expense of computerized control systems creation in production of highly engineered products on the basis of solving optimization problems on product startup estimation, estimation and redistribution of machine utilization, manufacturing process modelling.
Enhancement of a Methodology of Assembly Lathing Tools Quality Evaluation
Authors: Ostapenko M.S. , Tveryakov A.M.
Published: February 2016

New ways of determination of maximum efficiency and machinability temperatures were developed in order to reduce manpower input of methodology of assembly lathing tools quality evaluation.
Peculiarities of Quality Ensuring in Parts from Ti-Based Alloy VT6 with Ultrafine-Grained Structure
Authors: Safin Eduard Vilardovich , Smyslov Anatoliy Mikhailovich
Published: February 2016

The work analyzes application perspectives of Ti-based alloy VT6 (Ti-6Al-4V) with an ultrafine-grained structure with different grain sizes as structural material to produce high-load machine parts. The paper considers technological factors for ensuring quality of parts with account of assumed conditions of their exploitation, differently directed change of mechanical properties with reduction of an average grain size and choice of surface hardening technique.
Improvement of Methodology of Evaluation of Efficiency of the Metallurgical Complex Processes Development
Authors: Klochkov Yury , Gazizulina Albina
Published: February 2016

The article is devoted to the development of a model for monitoring the effectiveness of the organization development. It is suggested that the development is possible only when the norms and standards, upon which the method for determining the rate of development of the organization is proposed, are changed
Mathematical Model and Program Development for the Efficient Process Conditions Determination during FeC0.15Cr12Ni2 Steel Diamond Smoothing
Authors: Shvetcov Aleksei Nicolaevich , Skuratov Dmitrii Leonidovich
Published: February 2016

In this paper the mathematical model and the program based on this model for efficient process conditions during a diamond smoothing is introduced. The mathematical model has been tested with heatproof martensite category steel FeC0.15Cr12Ni2 by the synthetic diamond DSB-1 using as a smoothing tool. The mathematical model takes into account plastic deformation degree which could have both smoothing and reinforcing nature. Through the smoothing conditions the surface has a microroughnesses crumpling but reinforcing conditions involve also surface layer microhardness increasing.
Designing Forging and Die Tooling for the Manufacture of Turbine Engine Compressor Blades in Siemens NX
Authors: Goryainov D.S. , Anokhin V.V. , Shlyapugin Aleksey
Published: February 2016

For designing forging and die tooling for bulk forging a necessity in using the data of the geometry of the part produced arises. Obviously, the use as a data source for designing drawings of commonly applied in “manual alternate design” (without a computer) especially such complex parts as compressor blades is not perspective because of the complexity of developing theoretical contour specified by a point cloud. In this case the use of special tooling of direct modeling that provides changing the original model of the part developed by the designers is a perspective one. It should be taken into account during the process of forging and die tooling designing that it is necessary to register the special features of the technology, upon that, the technologist should be highly proficient in using the software. The work given describes the designing technique of gas turbine compressor blade with the account of using the potential of NX Siemens program.
Problems of Realization of Static-Dynamic Technologies and Ways of their Solution
Authors: Belyaeva Irina , Yusupov Rinat Yu. , Glushchenkov Vladimir
Published: February 2016

The paper presents examples of use of the created actuators in engineering - development of various test equipment including that for the needs of space materials-science (devices for measuring of hardness, devices for testing of samples in the conditions of the complex stressed state, testing of assembling joints and others); deforming equipment and devices (presses, dies for cutting - punching, calibration and others); devices used for elimination of consequences of hazard situations.
Actuator from a Material with the High-Temperature Shape Memory Effect and Examples of its Application in Engineering
Authors: Glushchenkov Vladimir , Yusupov Rinat Yu. , Alekhina Valentina , Egorov Yuri
Published: February 2016

The report provides designs of actuators from the shape memory material-nitinol. It is proposed to use rods, wire, sheets and tape as working elements of the actuators. Special attention is paid to the designs of composite multil-element actuators, working elements of which are connected in parallel or in series. The experimental technique and results of experiments on evaluation of stresses developed by such actuators are given. It is shown that using the composite actuators from thin working elements facilitates control over their heating and cooling.
Graphene Based Functional Hybrid Nanostructures: Preparation, Properties and Applications
Authors: Chatterjee Aniruddha , Hansora Dharmesh
Published: February 2016

The intent of this chapter is to provide a basic overview of recent advances in graphene based hybrid nanostructures including their preparation, properties and potential applications in various field. The development of graphene based functional materials, has shown their tremendous interest in areas of science, engineering and technology. These materials include graphene supported inorganic nanomaterials and films, graphene-metal decorated nanostructures, Core/shell structures of nanocarbon-graphene and graphene doped polymer hybrid nanocomposites etc. They have been prepared by various methods like chemical vapor deposition of hydrocarbon on metal surface, liquid phase exfoliation of graphite, chemical reduction of GO, silver mirror reaction, catalysis, in-situ hydroxylation and sono sol-gel route, respectively. The attractive properties of graphene and their derivatives filled with metal nanoparticles (e.g. Au, Ag, Pd, Pt, Ni, and Cu) have made them ideal templates. Graphene and their derivatives have also been decorated with various semiconductor nanomaterials (e.g. metal oxides and dioxides, metal sulfides). These metal decorated graphene nanostructures can be useful as functional hybrid nanomaterials in electronics, optics, and energy based products like solar cells, fuel cells, Li-ion batteries and supercapacitors, ion exchange and molecular adsorption.
Splenic RNA and MicroRNA Mimics Promote Complement Factor B Production and Alternative Pathway Activation via Innate Immune Signaling
Authors: Zou Lin , Feng Yan , Xu Ganqiong , Jian Wenling , Chao Wei
Published: February 2016

Complement factor B (cfB) is an essential component of the alternative pathway (AP) and plays an important role in the pathogenesis of polymicrobial sepsis. However, the mechanism leading to cfB production and AP activation during sepsis remains poorly understood. In this study, we found that plasma cell–free RNA was significantly increased following cecal ligation and puncture (CLP), an animal model of polymicrobial sepsis, and was closely associated with sepsis severity. Quantitative RT-PCR and microRNA (miRNA) array analysis revealed an increase in bacterial RNA and multiple host miRNAs (miR-145, miR-146a, miR-122, miR-210) in the blood following CLP. Treatment with tissue RNA or synthetic miRNA mimics (miR-145, miR-146a, miR-122, miR-34a) induced a marked increase in cfB production in cardiomyocytes or macrophages. The newly synthesized cfB released into medium was biologically active because it participated in AP activation initiated by cobra venom factor. Genetic deletion of TLR7 or MyD88, but not TLR3, and inhibition of the MAPKs (JNK and p38) or NF-κB abolished miR-146a–induced cfB production. In vivo, CLP led to a significant increase in splenic cfB expression that correlated with the plasma RNA or miRNA levels. Peritoneal injection of RNA or miR-146a led to an increase in cfB expression in the peritoneal space that was attenuated in MyD88-knockout or TLR7-knockout mice, respectively. These findings demonstrate that host cellular RNA and specific miRNAs are released into the circulation during polymicrobial sepsis and may function as extracellular mediators capable of promoting cfB production and AP activation through specific TLR7 and MyD88 signaling.