bluuebunny/crossref_metadata_2025_split huggingface dataset:
A Posteriori Error Estimates for Conservative Local Discontinuous GalerkinMethods for the Generalized Korteweg-de Vries Equation
Authors: Karakashian Ohannes , Xing Yulong 
Published: June 2016

AbstractWe construct and analyze conservative local discontinuous Galerkin (LDG) methods for the Generalized Korteweg-de-Vries equation. LDG methods are designed by writing the equation as a system and performing separate approximations to the spatial derivatives. The main focus is on the development of conservative methods which can preserve discrete versions of the first two invariants of the continuous solution, and a posteriori error estimates for a fully discrete approximation that is based on the idea of dispersive reconstruction. Numerical experiments are provided to verify the theoretical estimates.
Language, Colonial Attitude and War in Emecheta’s Destination Biafra: A Stylistic Critical Approach
Authors: Igbokwe I. Chima , Udumukwu Onyemaechi 
Published: June 2016

This study aims at examining the relevance of Sociolinguistic Functional Stylistics (SFS) in supplying a methodical structure upon which Emecheta’s Destination Biafra can be appreciated. Much of the critical attention on Emecheta has been centred on issues of gender and sexuality to the extent that ideological implications of language in her fiction have almost been ignored. This study applies as its theoretical framework Halliday’s Social Semiotic Structure with special reference to the context of situation discourse which not only interpretes relevant linguistic data but also establishes a link between people and the linguistic items used to describe them. This study adopts a qualitative research methodology for its data analysis which entails interpretative and definitive data analysis techniques. The study observes the presence of linguistic items such as verba sentiendi, lexical, syntactic negation, contextual use of language and paralinguistic devices such as figures of speech and so on in the novel under review. These linguistic choices determine the relationship between characters as they interact and also depict the specific function of language in operation. This study, therefore, recommends that the eclectic approach of Sociolinguistic Functional Stylistics should be applied to other sub-genres of prose, and other literary genres in order to open up a new vista in the appreciation of Emecheta’s works.
The relevance of Ali (Earth Deity): Ritual forms and processes in the 21st century Ikwerre of north eastern Niger Delta
Authors: Olumati Rowland 
Published: June 2016

The language of religion is often colored with rites and symbols. Man the “homoreligiosus” has in every age and culture, in his horizontal and vertical relationship with the sacred and the humans, evolved means of communicating and expressing his sentiments and belief patterns. Patent and evocative as they may be, rituals in symbolic forms have remained a rhythm of significance in man’s response to the sacred and his experience within the ecosystem. Configured in icons and expressed in metaphors, religious rituals and symbols convey a people’s religious consciousness, thoughtlogic and world view. This study generally focuses on the relevance of Ali ritual forms and processes among the Ikwerre ethnic nationality located in the North Eastern Niger Delta of Nigeria. The study supports the view of earlier scholars that Ali is Ikwerre's principal deity and the watch dog of Ikwerre moral ethos and has various manifestations of rituals associated with it in order to maintain social order in Ikwerre. Most importantly, this study negates the erroneous impression by some foreign scholars, that Africans were not objective in handling the issue of morality. Our finding shows that in the last one hundred years or so, there have been tremendous changes on beliefs and practices relating to Ali deity in her ritual forms and processes. However, the story of the impact of Christianity and other agents of modern change on Ali deity is one in which at the instant of these agents of modern change, some features of the belief system elapsed while others remain resolute.Keywords: Ali, Deity, Rituals, Niger Delta, Change
Of innocuousness and insolence: A dialogue on commitment in Nigerian drama
Authors: Mbachaga Desen Jonathan 
Published: June 2016

Questioning repression and exploitation especially of the working class is the hallmark of committed writing. This paper looks at the relevance of literature or art to life with a focus on the Nigerian experience. Our commitment as dramatists is to capture socio political experiences in our environments by clearly expressing the anxieties and sensibilities of our societies. The paper submits that the committed dramatist is one who knows his history and refuses to bow to the hegemonic structures of the system (status quo). Also, our writings as dramatists and artistes must not just offer mere social criticism but expose the social institutions in our communities and countries at large by properly delineating the conflicts and struggles between individuals and social classes. The paper concludes that, for our writing and indeed art to find relevance and make impact on the teeming population, it must provide ‘hope’ through reminding the world of a need to re – humanize with a focus on loving ourselves as humans, comforting ourselves and caring for ourselves.Keywords: committed writing, Nigerian Drama, arts for art’s sake
Effect of sporadic destratification, seasonal overturn, and artificial mixing on CH4 emissions from a subtropical hydroelectric reservoir
Authors: Guérin Frédéric , Deshmukh Chandrashekhar , Labat David , Pighini Sylvie , Vongkhamsao Axay , Guédant Pierre , Rode Wanidaporn , Godon Arnaud , Chanudet Vincent , Descloux Stéphane , Serça Dominique 
Published: June 2016

Abstract. Inland waters in general and freshwater reservoirs specifically are recognized as a source of CH4 into the atmosphere. Although the diffusion at the air–water interface is the most studied pathway, its spatial and temporal variations are poorly documented. We measured temperature and O2 and CH4 concentrations every 2 weeks for 3.5 years at nine stations in a subtropical monomictic reservoir which was flooded in 2008 (Nam Theun 2 Reservoir, Lao PDR). Based on these results, we quantified CH4 storage in the water column and diffusive fluxes from June 2009 to December 2012. We compared diffusive emissions with ebullition from Deshmukh et al. (2014) and aerobic methane oxidation and downstream emissions from Deshmukh et al. (2016). In this monomictic reservoir, the seasonal variations of CH4 concentration and storage were highly dependent on the thermal stratification. Hypolimnic CH4 concentration and CH4 storage reached their maximum in the warm dry season (WD) when the reservoir was stratified. Concentration and storage decreased during the warm wet (WW) season and reached its minimum after the reservoir overturned in the cool dry (CD) season. The sharp decreases in CH4 storage were concomitant with extreme diffusive fluxes (up to 200 mmol m−2 d−1). These sporadic emissions occurred mostly in the inflow region in the WW season and during overturn in the CD season in the area of the reservoir that has the highest CH4 storage. Although they corresponded to less than 10 % of the observations, these extreme CH4 emissions (> 5 mmol m−2 d−1) contributed up to 50 % of total annual emissions by diffusion. During the transition between the WD and WW seasons, a new emission hotspot was identified upstream of the water intake where diffusive fluxes peaked at 600 mmol m−2 d−1 in 2010 down to 200 mmol m−2 d−1 in 2012. The hotspot was attributed to the mixing induced by the water intakes (artificial mixing). Emissions from this area contributed 15–25 % to total annual emissions, although they occur in a surface area representative of less than 1 % of the total reservoir surface. We highly recommend measurements of diffusive fluxes around water intakes in order to evaluate whether such results can be generalized.
Ocean acidification in the subpolar North Atlantic: rates and mechanisms controlling pH changes
Authors: García-Ibáñez Maribel I. , Zunino Patricia , Fröb Friederike , Carracedo Lidia I. , Ríos Aida F. , Mercier Herlé , Olsen Are , Pérez Fiz F. 
Published: June 2016

Abstract. Repeated hydrographic sections provide critically needed data on and understanding of changes in basin-wide ocean CO2 chemistry over multi-decadal timescales. Here, high-quality measurements collected at twelve cruises carried out along the same track between 1991 and 2015 have been used to determine long-term changes in ocean CO2 chemistry and ocean acidification in the Irminger and Iceland basins of the North Atlantic Ocean. Trends were determined for each of the main water masses present and are discussed in the context of the basin-wide circulation. The pH has decreased in all water masses of the Irminger and Iceland basins over the past 25 years with the greatest changes in surface and intermediate waters (between −0.0010 ± 0.0001 and −0.0018 ± 0.0001 pH units yr−1). In order to disentangle the drivers of the pH changes, we decomposed the trends into their principal drivers: changes in temperature, salinity, total alkalinity (AT) and total dissolved inorganic carbon (both its natural and anthropogenic components). The increase in anthropogenic CO2 (Cant) was identified as the main agent of the pH decline, partially offset by AT increases. The acidification of intermediate waters caused by Cant uptake has been reinforced by the aging of the water masses over the period of our analysis. The pH decrease of the deep overflow waters in the Irminger basin was similar to that observed in the upper ocean and was mainly linked to the Cant increase, thus reflecting the recent contact of these deep waters with the atmosphere.
The influence of Holocene vegetation changes on topography and erosion rates: a case study at Walnut Gulch Experimental Watershed, Arizona
Authors: Pelletier Jon D. , Nichols Mary H. , Nearing Mark A. 
Published: June 2016

Abstract. Quantifying how landscapes have responded and will respond to vegetation changes is an essential goal of geomorphology. The Walnut Gulch Experimental Watershed (WGEW) offers a unique opportunity to quantify the impact of vegetation changes on landscape evolution over geologic timescales. The WGEW is dominated by grasslands at high elevations and shrublands at low elevations. Paleovegetation data suggest that portions of WGEW higher than approximately 1430 m a.s.l. have been grasslands and/or woodlands throughout the late Quaternary, while elevations lower than 1430 m a.s.l. changed from a grassland/woodland to a shrubland ca. 2–4 ka. Elevations below 1430 m a.s.l. have decadal timescale erosion rates approximately 10 times higher, drainage densities approximately 3 times higher, and hillslope-scale relief approximately 3 times lower than elevations above 1430 m. We leverage the abundant geomorphic data collected at WGEW over the past several decades to calibrate a mathematical model that predicts the equilibrium drainage density in shrublands and grasslands/woodlands at WGEW. We use this model to test the hypothesis that the difference in drainage density between the shrublands and grassland/woodlands at WGEW is partly the result of a late Holocene vegetation change in the lower elevations of WGEW, using the upper elevations as a control. Model predictions for the increase in drainage density associated with the shift from grasslands/woodlands to shrublands are consistent with measured values. Using modern erosion rates and the magnitude of relief reduction associated with the transition from grasslands/woodlands to shrublands, we estimate the timing of the grassland-to-shrubland transition in the lower elevations of WGEW to be approximately 3 ka, i.e., broadly consistent with paleovegetation studies. Our results provide support for the hypothesis that common vegetation changes in semi-arid environments (e.g., from grassland to shrubland) can change erosion rates by more than an order of magnitude, with important consequences for landscape morphology.
mizuRoute version 1: a river network routing tool for a continental domain water resources applications
Authors: Mizukami Naoki , Clark Martyn P. , Sampson Kevin , Nijssen Bart , Mao Yixin , McMillan Hilary , Viger Roland J. , Markstrom Steve L. , Hay Lauren E. , Woods Ross , Arnold Jeffrey R. , Brekke Levi D. 
Published: June 2016

Abstract. This paper describes the first version of a stand-alone runoff routing tool, mizuRoute. The mizuRoute tool post-processes runoff outputs from any distributed hydrologic model or land surface model to produce spatially distributed streamflow at various spatial scales from headwater basins to continental-wide river systems. The tool can utilize both traditional grid-based river network and vector-based river network data. Both types of river network include river segment lines and the associated drainage basin polygons, but the vector-based river network can represent finer-scale river lines than the grid-based network. Streamflow estimates at any desired location in the river network can be easily extracted from the output of mizuRoute. The routing process is simulated as two separate steps. First, hillslope routing is performed with a gamma-distribution-based unit-hydrograph to transport runoff from a hillslope to a catchment outlet. The second step is river channel routing, which is performed with one of two routing scheme options: (1) a kinematic wave tracking (KWT) routing procedure; and (2) an impulse response function – unit-hydrograph (IRF-UH) routing procedure. The mizuRoute tool also includes scripts (python, NetCDF operators) to pre-process spatial river network data. This paper demonstrates mizuRoute's capabilities to produce spatially distributed streamflow simulations based on river networks from the United States Geological Survey (USGS) Geospatial Fabric (GF) data set in which over 54 000 river segments and their contributing areas are mapped across the contiguous United States (CONUS). A brief analysis of model parameter sensitivity is also provided. The mizuRoute tool can assist model-based water resources assessments including studies of the impacts of climate change on streamflow.
Development and calibration of an automatic spectral albedometer to estimate near-surface snow SSA time series
Authors: Picard Ghislain , Libois Quentin , Arnaud Laurent , Verin Gauthier , Dumont Marie 
Published: June 2016

Abstract. Spectral albedo of the snow surface in the visible/near-infrared range has been measured for 3 years by an automatic spectral radiometer installed at Dome C (75° S, 123° E) in Antarctica in order to retrieve the specific surface area (SSA) of superficial snow. This study focuses on the uncertainties of the SSA retrieval due to instrumental and data processing limitations. We find that when the solar zenith angle is high, the main source of uncertainties is the imperfect angular response of the light collectors. This imperfection introduces a small spurious wavelength-dependent trend in the albedo spectra which greatly affects the SSA retrieval. By modeling this effect, we show that for typical snow and illumination conditions encountered at Dome C, retrieving SSA with an accuracy better than 15 % (our target) requires the difference of response between 400 and 1100 nm to not exceed 2 %. Such a small difference can be achieved only by (i) a careful design of the collectors, (ii) an ad hoc correction of the spectra using the actual measured angular response of the collectors, and (iii) for solar zenith angles less than 75°. The 3-year time series of retrieved SSA features a 3-fold decrease every summer which is significantly larger than the estimated uncertainties. This highlights the high dynamics of near-surface SSA at Dome C.
Microincision 25G Pars Plana Vitrectomy with Peeling of the Inner Limiting Membrane and Air Tamponade in Idiopathic Macular Hole
Authors: Hejsek Libor , Stepanov Alexandr , Dusova Jaroslava , Marak Jan , Nekolova Jana , Jiraskova Nada , Codenotti Marco 
Published: June 2016

Purpose To evaluate the success of a mini-invasive technique for operation of idiopathic macular hole (IMH). Methods We retrospectively examined 29 patients (30 eyes) in whom 25-G pars plana vitrectomy (PPV), peeling of the inner limiting membrane (ILM), and application of air tamponade were performed. The group of the patients included 7 males and 22 females (76%), age range 57-79 years (median 70). The follow-up period was 3-47 months (median 17). Results Pars plana vitrectomy was indicated only in the stages of full-thickness macular hole. Prior to operation, 13 eyes (43%) were in stage 2, 15 eyes (50%) in stage 3, and 2 eyes (7%) in stage 4. The IMH healed in 28 eyes after operation. Persistence of IMH occurred in 2 eyes (7%). After subsequent reoperation with extension of the peeling zone of the ILM and gas tamponade (with 10% C3F8), these macular holes also healed (100%). Prior to carrying out PPV, best-corrected visual acuity (BCVA) ranged between 20/40 and 20/500 (median 20/125). At the end of the follow-up period, BCVA was improved to 20/40 (median). The change in the final BCVA compared to the initial visual acuity was statistically significant (p = 0.008; Wilcoxon). Conclusions The 25-G PPV with peeling of the ILM and air tamponade is an effective technique and presents no increased risks in comparison with routine procedures. The main benefit of the intervention is its good tolerance by the patient, particularly with respect to painfulness and postoperative irritation.
Salvaging Deep Anterior Lamellar Keratoplasty with Microbubble Incision Technique in Failed “Big Bubble” Cases: An Update Study
Authors: Banerjee Sanjib , Li He J. , Tsaousis Konstantinos T. , Tabin Geoffrey C. 
Published: June 2016

Purpose To report the achievement rate of bare Descemet membrane (DM) dissection with the help of microbubble incision technique in eyes with failed big bubble formation and to investigate the mechanism of the microbubble rescue technique through ex vivo imaging of human cadaver corneas. Methods This retrospective clinical study included 80 eyes of 80 patients that underwent deep anterior lamellar keratoplasty (DALK). In 22/80 (27.5%) cases, big bubble dissection failed. After puncturing the microbubbles, viscodissection helped to achieve separation of DM from the remaining stroma. In addition, an ex vivo study with human cadaver cornea specimens, gross photography, and anterior segment optical coherence tomography imaging was accomplished ex vivo to explore the mechanism of this method. Results Microbubble dissection technique led to successful DALK in 19 of 22 cases of failed big bubble. Microperforation occurred in 3 eyes. Deep anterior lamellar keratoplasty was completed without any complications in 2 out of the 3 eyes with microperforation. In 1 eye, conversion to penetrating keratoplasty was required. Microbubble-guided viscodissection achieved 95.4% (21/22) success in exposing bare DM in failed big-bubble cases of DALK. Anterior segment optical coherence tomography imaging results of cadaver eyes showed where these microbubbles were concentrated and their related size. Conclusions Microbubble-guided DALK should be considered an effective rescue technique in achieving bare DM in eyes with failed big bubble. Our ex vivo experiment illustrated the possible alterations in cornea anatomy during this technique.
Retinal Nerve Fiber Layer Thickness by Stratus and Cirrus OCT in Retrobulbar Optic Neuritis and Nonarteritic Ischemic Optic Neuropathy
Authors: Giambene Barbara , Virgili Gianni , Menchini Ugo 
Published: June 2016

Purpose To compare retinal nerve fiber layer thickness (RNFLT) measurements by Stratus and Cirrus optical coherence tomography (OCT) and to evaluate agreement between the 2 instruments in retrobulbar optic neuritis (RON), nonarteritic ischemic optic neuropathy (NAION), and healthy controls. Methods A total of 89 eyes with RON, 92 with NAION (6 to 12 months after diagnosis of acute disease), and 159 control eyes were studied. Average RNFLT was measured by Stratus and Cirrus OCTs. Comparisons among groups were performed by analysis of variance. Agreement between the 2 instruments was assessed using intraclass correlation coefficient (ICC) with 95% confidence interval (CI) and Bland-Altman analysis. Statistical significance was set at p≤0.05. Results Average RNFLT was lower in NAION eyes than in RON and control ones using both OCT devices (60.0 ± 1.2, 69.9 ± 1.2, and 97.4 ± 0.9 μm, p<0.001 by Cirrus; 49.7 ± 1.5, 65.9 ± 1.9, and 99.2 ± 1.3 μm, p<0.001 by Stratus). The RNFLT values were higher with Cirrus than with Stratus in NAION (+10.30 μm, confidence interval [CI] 7.82-12.79 μm) and RON (+4.01 μm, CI 1.32-6.70 μm) eyes, and slightly lower in control ones (-1.75 μm, CI -3.51 to 0.01 μm). A stronger agreement between the 2 instruments was found in control and RON eyes than in NAION ones (ICC 0.682, CI 0.566-0.771; 0.635, CI 0.467-0.758; 0.321, CI 0.132-0.472, respectively). Conclusions Both Stratus and Cirrus OCT can identify RNFLT reduction in previous RON and NAION. Absolute RNFLT values differ between the 2 instruments; hence they are not to be considered interchangeable.
Light-Storing Photocatalyst: The Possibility of Activating Titanium Dioxide by Photoluminescence
Authors: Cattini Stefano , Bondioli Federica 
Published: June 2016

Introduction The aim of the present work was to analyze the possibility of creating a light-storing photocatalyst material, a system that couples a phosphorescent substrate with a titania coating. The substrate could activate the titanium dioxide coating even in condition of darkness thanks to its light emission. This improvement of absorption can be achieved because the titania semiconductor is irradiated both by the direct light and by the luminescent substrate which is activated at the same time. Methods TiO2-based sol-gel solutions were deposited on commercial borosilicate glasses containing 2 different phosphorescent pigments (emission peaks at 470 and 520 nm, respectively). Particular attention was paid to optimize the film-substrate adhesion by using a scratch test to evaluate the optimal temperature of the post- treatment step. Results and discussion The main result is that when irradiated the photoluminescent pigments allow an increase in the photocatalytic acitivity of the coatings. The pigments are able to convert the ultraviolet component of light in order to increase the amount of energy that can be absorbed by titania. Moreover, the hydrophilicity test showed that in the absence of irradiation the phosphorescent samples are characterized by a lower loss of superhydrophilicity.
Incorporation of an Antibiotic in Poly(Lactic Acid) and Polypropylene by Melt Processing
Authors: Scaffaro Roberto , Botta Luigi , Maio Andrea , Gallo Giuseppe 
Published: June 2016

Purpose In this work an antibiotic, ciprofloxacin (CFX), was incorporated into 2 different polymeric matrices, poly(lactic acid) (PLA) and polypropylene (PP), to provide them with antimicrobial properties. The influence of CFX content on release kinetics and on antimicrobial and mechanical properties was evaluated. Methods CFX was incorporated into both the polymers by melt mixing. Results The effect of CFX incorporation was found to strongly depend on which polymer matrix was used. In particular, the antimicrobial tests revealed that PLA samples containing CFX produced no inhibition zone and only a slight antibacterial activity was observed when the highest concentration of CFX was added to PLA. On the contrary, PP-based materials incorporating CFX, even those containing the smallest concentration of antibiotic, showed antimicrobial activity. These results were found to be in good agreement with the evaluation of the CFX release. Conclusions The negative findings of PLA-based systems are attributed to degradation phenomena that occur during the melt processing, involving some interaction between PLA and CFX. A proposed reaction mechanism between CFX and PLA occurring in the melt is presented.