bluuebunny/crossref_metadata_2025_split huggingface dataset:
Structure and morphological stability of (Lu1–xEux)2O3 thin films
Authors: Bezkrovnyi O. S. , Babayevskaya N. V. , Mateychenko P. V. , Vovk O. M. , Doroshenko A. G. , Sofronov D. S. 
Published: February 2014

(Lu1–xEux)2O3 smooth, crack‐free, transparent films were prepared by the Pechini sol–gel method and a spin‐coating technique. Thermogravimetric analysis, differential thermal analysis and FITR spectroscopy were used to study the chemical processes during annealing of the films. Film structure, morphology and optical properties were investigated. X‐ray diffraction (XRD) analysis reveals the cubic phase of (Lu1–xEux)2O3 films annealed in the 600–1000 °C temperature range. Smooth and crack‐free films with thicknesses of 250–1000 nm were obtained in the 600–800 °C temperature range. The thickness upper limit (1000 nm) of morphological stability of films (Lu1–xEux)2O3 on sapphire substrates has been studied.
Data traffic‐based analysis of delay and energy consumption in cognitive radio networks with and without resource reservation
Authors: Elmachkour Mouna , Kobbane Abdellatif , Sabir Essaid , Ben‐othman Jalel , El koutbi Mohammed 
Published: February 2014

SummaryA new opportunistic cross‐layer MAC protocol involving channel allocation and packet scheduling for cognitive radio networks is proposed. Cognitive radio allows secondary users (SUs) to exploit the available portions of the licensed spectrum bands without interfering with primary users. In particular, we consider a cognitive radio system, where SUs are equipped with two transceivers: a control transceiver and a software‐defined radio transceiver. Data traffic characteristics of SUs are considered to ameliorate system performance. So, we propose a mechanism of resource reservation to improve QoS requirements that favors successful SUs to transmit data during x time slots without interfering with primary users. The key novelty of this paper is giving priority for SUs with important data traffic and which frequently solicits data channels to transmit for the remaining time of the ongoing time slot and for the next time slots directly after checking the channel availability. We develop a new analytical model to evaluate delay parameter for two scenarios with and without resource reservation and we then investigate the impact of those scenarios on the energy consumption. We show through simulations that cognitive radio performances increase noticeably with the proposed scheme. Copyright © 2014 John Wiley & Sons, Ltd.
Interspecific diversity in root antioxidative enzyme activities reflect root turnover strategies and preferred habitats in wetland graminoids
Authors: Yücel Çağdaş Kera , Bor Melike , Ryser Peter 
Published: February 2014

AbstractAntioxidant enzymes protect cells against oxidative stress and are associated with stress tolerance and longevity. In animals, variation in their activities has been shown to relate to species ecology, but in plants, comparative studies with wild species are rare. We investigated activities of five antioxidant enzymes – ascorbate peroxidase (APX), catalase (CAT), glutathione reductase (GR), peroxidase (POX), and superoxide dismutase (SOD) – in roots of four perennial graminoid wetland species over a growing season to find out whether differences in root turnover or habitat preferences would be associated with variation in seasonal patterns of antioxidant enzyme activities. The investigated species differ in their root turnover strategies (fine roots senesce in the fall or fine roots survive the winter) and habitat preferences (nutrient‐poor vs. productive wetlands). Roots were collected both in the field and from garden‐grown plants. Antioxidant enzyme activities were higher and lipid peroxidation rates lower in species with annual root systems, and for species of the nutrient‐poor wetland, compared with perennial roots and species of productive wetlands, respectively. There was variation in the activities of individual antioxidant enzymes, but discriminant analyses with all enzymes revealed a clear picture, indicating consistent associations of antioxidant enzyme activities with the type of root turnover strategy and with the preferred habitat. We conclude that antioxidant enzyme activities in plant roots are associated with the species' ecological strategies and can be used as traits for the characterization of the species' position along plant economics spectrum.
Novel Lu3+ Carbon Paste Electrode Based on Functionalized Multiwalled Carbon Nanotubes
Authors: Tamaddon Atefeh , Amiri Rahebeh , Hazini Fatemeh 
Published: February 2014

AbstractA novel carbon paste ion selective electrode for determination of trace amount of lutetium was prepared. Modified (functionalized) multiwalled carbon nanotubes (f‐MWCNTs) were used for improvement of a lutetium carbon paste sensor response. MWCNTs have a good conductivity which helps the transduction of the signal in carbon paste electrode. In this work it is shown that introducing certain functional groups on MWCNTs can improve the electrode signals. The electrode composition of 20 % paraffin oil, 56 % graphite powder, 18 % ionophore and 6 % f‐MWCNTs showed the stable potential response to Lu3+ ions with the Nernstian slope of 21.1 (±0.3) mV decade−1 over a wide linear concentration range of 1.0×10−6–1.0×10−1 mol L−1. The electrode has fast response time (<15 s) and long term stability (about one month).
Organic solvent‐assisted crystallization of inorganic salts from acidic media
Authors: Moldoveanu Georgiana A. , Demopoulos George P. 
Published: February 2014

AbstractBACKGROUNDSolvent displacement crystallization (SDC) provides an energy‐efficient alternative to evaporative crystallization potentially leading to crystal products of superior quality, both in terms of purity and size, due to better supersaturation control. The present work investigates the SDC process in terms of appropriate organic solvent selection and application to several metal (K+, Na+, Mg2+ Fe2+, Cu2+, Ni2+, Co2+, Zn2+, Fe3+ and Al3+) sulfate and chloride systems of hydrometallurgical interest.RESULTSCriteria for the screening of organic compounds with suitable physical and chemical properties have been established and 2‐propanol was selected as an effective salting out agent to precipitate crystalline metal sulfates of practical interest; differences in crystallization behaviour among the various salts were linked to the hydration energy of the cation. None of the tested metal chlorides could be successfully separated, due to enhanced metal chloride solubility in non‐aqueous solvents relative to water by formation of chloro‐complexes with larger stability constants.CONCLUSIONSThe solvent displacement crystallization process was investigated and selection criteria for the organic solvent were established. 2‐propanol proved to be the most effective salting out agent for metal sulfates resulting in > 90% cation removal. By contrast none of the metal chlorides could be successfully separated due to salting‐in behaviour. © 2014 Society of Chemical Industry
X‐ray investigations of GaInN single quantum wells grown by atomic layer epitaxy and metalorganic vapor phase epitaxy
Authors: Ju Guangxu , Kato Yoshihiro , Honda Yoshio , Tabuchi Masao , Takeda Yoshikazu , Amano Hiroshi 
Published: February 2014

AbstractA set of GaN/GaInN single quantum wells (SQWs) were grown on c‐plane GaN/sapphire templates using metal organic vapor phase epitaxy (MOVPE) and atomic layer epitaxy (ALE). The structural information on the interfaces and surfaces was obtained by fitting the experimental X‐ray spectra and was compared between MOVPE and ALE mode. The X‐ray crystal truncation rod (CTR) scattering measurement results showed that the samples grown by ALE had sharper interfaces than those grown by MOVPE. Both the X‐ray reflectivity (XRR) curve‐fitting results and atomic force microscope (AFM) results indicated that the surfaces of the ALE‐grown SQWs were smoother than those of MOVPE‐grown SQWs. (© 2014 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
“A Little Book of Logic” – Reconstructing Colonial Arts of Suasion at Government College, Umuahia
Authors: Ochiagha Terri 
Published: February 2014

AbstractMemories of political pedagogies in the elite colonial classroom are typically fragmentary and constitute limited historical evidence. But when contextualized and used in combination with coetaneous sources, such as textbooks and lesson notes, they can be crucial in the reconstruction of the transmission of political knowledge, its classroom assimilation and postcolonial negotiation. This article pieces together a number of unconnected but mutually consistent epiphanic moments in the life-writing and interviews of writers Chinua Achebe and Chike Momah, tracing and identifying a mysterious textbook of logic – R.W. Jepson’sClear Thinking(1936) – and its use as a tool to rein in and redirect anti-colonial nationalist undercurrents at Government College, Umuahia, the elite colonial school famous for having produced eight renowned Nigerian writers.
Modelling size segregation of granular materials: the roles of segregation, advection and diffusion
Authors: Fan Yi , Schlick Conor P. , Umbanhowar Paul B. , Ottino Julio M. , Lueptow Richard M. 
Published: February 2014

AbstractPredicting segregation of granular materials composed of different-sized particles is a challenging problem. In this paper, we develop and implement a theoretical model that captures the interplay between advection, segregation and diffusion in size bidisperse granular materials. The fluxes associated with these three driving factors depend on the underlying kinematics, whose characteristics play key roles in determining particle segregation configurations. Unlike previous models for segregation, our model uses parameters based on kinematic measures from discrete element method simulations instead of arbitrarily adjustable fitting parameters, and it achieves excellent quantitative agreement with both experimental and simulation results when applied to quasi-two-dimensional bounded heaps. The model yields two dimensionless control parameters, both of which are only functions of control parameters (feed rate, particle sizes, and system size) and kinematic parameters (diffusion coefficient, flowing layer depth, and percolation velocity). The Péclet number, $\mathit{Pe}$, captures the interplay of advection and diffusion, and the second dimensionless parameter, $\Lambda $, describes the interplay between segregation and advection. A parametric study of $\Lambda $ and $\mathit{Pe}$ demonstrates how the particle segregation configuration depends on the interplay of advection, segregation and diffusion. The model can be readily adapted to other flow geometries.
Categorizing threatened species: an analysis of the Red List of the flora of Brazil
Authors: Moraes M. A. , Borges R.A.X. , Martins E. M. , Fernandes R. A. , Messina T. , Martinelli G. 
Published: February 2014

AbstractIn Brazil most of the effort for the conservation of plant species has comprised evaluation of taxa for the Lista Oficial das Espécies Ameaçadas de Extinção da Flora Brasileira (Official Threatened Flora Species List), and little has been done to conserve individual species. This is a result of the listing process being interpreted as the final goal rather than as a means to achieve conservation effectiveness. In addition, a variety of systems for the classification of extinction risk have been applied, resulting in an inaccurate view of the conservation status of the flora of the country. Here we review the national listing process to highlight the strengths and weaknesses of the Official Threatened Flora Species List. We used all available information to compile a list of taxa officially recorded as threatened in Brazil. The list was revised using the Flora do Brasil database. The resulting list has 4,967 taxa in 1,235 genera and 232 families. Despite controversies about advances in the Red Listing process, several improvements have been made at the institutional level, such as: (1) improving conservation databases, (2) developing information systems, and (3) increasing the number of taxonomists working in conservation biology. However, there is still no classification system for extinction risk that facilitates standardization of the listing process at the national level. In addition, regulatory processes related to the conservation of threatened plant species are not up-to-date with the conceptual and methodological advances made by the scientific community. We conclude that adjustments are needed to ensure the effectiveness of the conservation of plant species in Brazil.
Progress and prospects for targeting Hsp90 to treat fungal infections
Authors: VERI AMANDA , COWEN LEAH E. 
Published: February 2014

SummaryFungal pathogens pose a major threat to human health worldwide. They infect billions of people each year, leading to at least 1·5 million deaths. Treatment of fungal infections is difficult due to the limited number of clinically useful antifungal drugs, and the emergence of drug resistance. A promising new strategy to enhance the efficacy of antifungal drugs and block the evolution of drug resistance is to target the molecular chaperone Hsp90. Pharmacological inhibitors of Hsp90 function that are in development as anticancer agents have potential to be repurposed as agents for combination antifungal therapy for some applications, such as biofilm infections. For systemic infections, however, effective combination therapy regimens may require Hsp90 inhibitors that can selectively target Hsp90 in the pathogen, or alternate strategies to compromise function of the Hsp90 chaperone machine. Selectively impairing Hsp90 function in the pathogen could in principle be achieved by targeting Hsp90 co-chaperones or regulators of Hsp90 function that are more divergent between pathogen and host than Hsp90. Antifungal combination therapies could also exploit downstream effectors of Hsp90 that are critical for fungal drug resistance and virulence. Here, we discuss the progress and prospects for establishing Hsp90 as an important therapeutic target for life-threatening fungal infections.
Toxoplasma gondiiHsp90: potential roles in essential cellular processes of the parasite
Authors: ANGEL SERGIO O. , FIGUERAS MARIA J. , ALOMAR MARIA L. , ECHEVERRIA PABLO C. , DENG BIN 
Published: February 2014

SUMMARYHsp90 is a widely distributed and highly conserved molecular chaperone that is ubiquitously expressed throughout nature, being one of the most abundant proteins within non-stressed cells. This chaperone is up-regulated following stressful events and has been involved in many cellular processes. InToxoplasma gondii, Hsp90 could be linked with many essential processes of the parasite such as host cell invasion, replication and tachyzoite-bradyzoite interconversion. A Protein-Protein Interaction (PPI) network approach of TgHsp90 has allowed inferring how these processes may be altered. In addition, data mining ofT. gondiiphosphoproteome and acetylome has allowed the generation of the phosphorylation and acetylation map of TgHsp90. This review focuses on the potential roles of TgHsp90 in parasite biology and the analysis of experimental data in comparison with its counterparts in yeast and humans.
The population size and breeding range of the Scaly-sided MerganserMergus squamatus
Authors: SOLOVYEVA DIANA V. , LIU PEIQI , ANTONOV ALEXEY I. , AVERIN ANDREY A. , PRONKEVICH VLADIMIR V. , SHOKHRIN VALERY P. , VARTANYAN SERGEY L. , CRANSWICK PETER A. 
Published: February 2014

SummaryBased on surveys during 2000–2012 and best available knowledge, we estimate the global population size of the Endangered Scaly-sided MerganserMergus squamatusto be c.1,940 pairs (or c.4,660 birds prior to reproduction). In Russia, surveys identified the breeding range in the Sikhote-Alin mountain range and the area adjoining the lower Amur River. Particular effort was made to define the edge of the range. Breeding densities in the Sikhote-Alin were applied to un-surveyed rivers within the range to estimate overall numbers. The breeding range comprises c.7,800 km of 120 rivers: 6,800 km in Russia, 600 in China and 400 in DPR Korea. In Russia it comprises 88 rivers of both the western and eastern slopes of the Sikhote-Alin Range, and two small isolated areas, one in central Khabarovsk and the other in the Jewish Autonomous Oblast. All known and potential breeding areas were surveyed in China, where the breeding range comprises the western slope of the Changbai Mountains, and one isolated river system in the Lesser Xingan Mountains. Scaly-sided Mergansers are also assumed to breed on the eastern slope of the Changbai Mountains in DPR Korea. No recent surveys have been made there but numbers were estimated by applying densities from China to rivers with apparently suitable habitat. Detailed examination of past records suggests that an earlier claim of breeding Scaly-sided Mergansers on the Dep River was erroneous and we conclude that the breeding range never extended as far west as has been portrayed in most literature. The lack of comparable surveys previously precludes an assessment of change in population range or size, though it seems inevitable that habitat loss in China is likely to have resulted in some loss of range and numbers, particularly in Heilongjiang Province, in recent decades.
Exploring the Limits to Observational Diffuse Interstellar Band Studies
Authors: Foing B. H. 
Published: February 2014

AbstractThe status of DIB research (Herbig 1995) has strongly advanced since the DIB conference in Boulder in 1994. In the same year we reported the discovery of two near IR diffuse bands coincident with C60+, that was confirmed in subsequent years. Since then a number of DIB observational studies have been published such as DIB surveys, measurements of DIB families, correlations and environment dependences as well as DIBs in extra-galactic sources. Resolved substructures were measured and compared to predicted rotational contours of large molecules. Polarisation studies provided constraints on possible carrier molecules and upper limits. DIBs carriers have been linked with several classes of organic molecules observed in the interstellar medium, in particular to the UIR bands (assigned to PAHs), the Extended Red Emission (ERE) or the recently detected Anomalous Microwave Emission (AME, assigned to spinning dust). In particular fullerenes and PAHs have been proposed to explain some DIBs and specific molecules were searched for in DIB spectra. DIB carriers could be present in various dehydrogenation and ionization states. Experiments in the laboratory and in space contribute to our understanding of the photo-stability of possible DIB carriers. In summary, the status of DIB research in the last 20 years has strongly advanced. We review DIB observational results and their interpretation and introduce the relevant plenary discussion.
Probing the Local Bubble with Diffuse Interstellar Bands
Authors: Farhang A. , Khosroshahi H. G. , Javadi A. , van Loon J. 
Published: February 2014

AbstractThe Sun is located inside an enormous local cavity filled with a million degree, ionized hydrogen gas and surrounded by a wall of dense and cold gas, this cavity is known as the Local Bubble (LB). Since the tempreture of Local Bubble is high, the typical singly-ionized atoms or molecules can not survive at this high tempreture. To overcome this problem we should probe the Local Bubble using species which survive under this condition so we have done a whole sky survey in north hemisphere by observing absorptions in the Diffuse Interstellar Bands (DIBs) for sight-lines with distance >300 pc. We have done 30 nights observation and have observed 473 bright stars. We found that the correlations between 5780 Å DIBs and Na I D doublets inside of the LB is much more than carriers outside of the LB.
The Properties of Near-Infrared Diffuse Interstellar Bands
Authors: Rawlings M. G. , Adamson A. J. , McCall B. J. , Kerr T. H. 
Published: February 2014

AbstractIn addition to the hundreds of known visual-wavelength Diffuse Interstellar Bands (DIBs), a number of DIBs in the near-infrared (NIR) are now also known to exist. We present here high-resolution UKIRT echelle spectroscopy of two of the NIR DIBs toward sightlines exhibiting a range of visual extinctions. Variations in the strengths and profile shapes of the bands are considered in the context of known properties of the narrow DIBs at visual wavelengths.
Type Ia Supernovae as Probes of the Interstellar Medium in Galaxies
Authors: Cox N. L. J. , Patat F. 
Published: February 2014

AbstractWe present and discuss recent results from observations of bright Type Ia supernovae as probes of physical and chemical condtions of extra-galactic interstellar clouds. To illustrate the case we present new results obtained for SN 2009ig.
C2 and Diffuse Interstellar Bands
Authors: Kaźmierczak M. , Schmidt M. , Weselak T. , Galazutdinov G. , Krełowski J. 
Published: February 2014

AbstractC2, the simplest multicarbon molecule is a useful astronomical tool, because the analysis of its lines allows to determine the physical conditions in interstellar clouds. C2 abundances give information about the chemistry of interstellar clouds, especially on the pathway to the formation of long-chain carbon molecules, which may be connected with carriers of diffuse interstellar bands (Douglas 1977, Thorburn et al. 2003). Here we summarize all relations between C2 and diffuse interstellar bands (DIBs).
Relating Diffuse Interstellar Band Strengths to Line of Sight Properties
Authors: Rashedi H. , Cami J. , Cox N. L. J. , van Winckel H. 
Published: February 2014

AbstractWe present a preliminary analysis of a set of optical (3800-8800 Å) high resolution (R = 80,000) spectra for 69 diffuse interstellar band targets. We carried out a sensitive search for interstellar features in the wavelength range 8470-8740 Å that will be covered by the upcoming GAIA mission. We also investigate how the λ8620Å DIB strength varies as a function of other interstellar parameters (other DIBs, E(B-V) and atomic and molecular column densities).
Polyynyl-Substituted PAH Molecules and DIB Carriers
Authors: Rouillé G. , Jäger C. , Huisken F. , Henning T. 
Published: February 2014

AbstractPolycyclic aromatic hydrocarbon (PAH) molecules have been long considered promising candidates for the carriers of the diffuse interstellar bands (DIBs). The PAH-DIB hypothesis, however, raises two major issues. First, the number of interstellar PAH species is potentially orders of magnitude larger than the number of DIBs. Second, the absorption spectrum of a PAH is in general dominated by bands found at UV wavelengths while, conversely, DIBs are absent from the UV wavelength domain and arise at visible and near IR wavelengths. These issues do not necessarily weaken the PAH-DIB hypothesis and can actually allow us to refine it. In that context, we analyze the UV/vis absorption spectra of PAH molecules isolated in Ne matrices and propose that polyynyl-substituted PAHs, or similar species, are valid candidates for the carriers of the DIBs. Finally, a possible lifecycle for DIB-carrying PAHs is presented.