bluuebunny/crossref_metadata_2025_split huggingface dataset:
Floral Resources Sustaining African Meliponine Bee Species (Hymenoptera: Meliponini) in a Fragile Habitat of Kenya
Authors: Bobadoye Bridget O. , N. Ndegwa Paul , Irungu Lucy , Ayuka Fombong , Kajobe Robert 
Published: December 2016

A vast majority of insects visit flowers for food, generally termed as floral rewards. Detailed insights on flowering phenology of plants could give a hint of habitat status and the extent to which such landscapes could support insect pollinators to render both direct and indirect ecosystem services. This study monitored flowering plants which could potentially provide both pollen and nectar sources to four African meliponine bee species (Apidae: Meliponini) naturally occurring in six diverse habitat gradients of the eastern arc mountains (Taita hills) of Kenya. Blooming sequences of identified flowering plants overlapped across seasons with approximately 80 different plant species belonging to 34 families recorded, with the highest proportions from Fabaceae and Asteraceae families dominating flowering plants that were visited (67% of the visits). A flowering calendar is presented to indicate the phenological pattern of all identified floral resources. Hypotrigona gribodoi being the most abundant species had the highest visitation rates on plants belonging to Fabaceae and Asteraceae families, followed by Meliponula ferruginea (black), Plebeina hildebrandti and Hypotrigona ruspolii. This indicates that such fragile habitat could invariably sustain nutritional requirements essential for the survival of insect pollinators such as native meliponine bee species, though bee abundance at flowers did not significantly correlate to food availability (expressed by flowering plant richness).
Spatial Inequality and Uneven Development: The Local Stratification of Poverty in Appalachia
Authors: Greenberg Pierce 
Published: December 2016

AbstractScholars have long analyzed the persistence of Appalachian poverty in counties, but less is known about the dimensions of poverty at smaller geographic levels. This paper builds upon the concept of spatial inequality, which explains how socio-economic disadvantage is segregated across residential space based on race and class. I extend the study of spatial inequality to Appalachia by investigating how local poverty is stratified across the region. The literature suggests two historical processes that could lead to spatial stratification in Appalachia: (1) the concentration of local economic opportunity in county seat cities, and (2) historical economic development processes that emphasized growth and marginalized the most rural areas of the region. Therefore, I analyze whether distance to a county seat influences poverty rates in Appalachian neighborhoods. The results indicate that distance to a county seat has a curvilinear ‘U-shaped’ relationship with poverty: the poorest neighborhoods, on average, are likely to be closest and farthest away from county seats. While data limitations exist, these findings emphasize the importance of place-based, subcounty initiatives for poverty alleviation in Appalachia.
Thieves Stealing from Thieves, Victims from Victims: The Culture, Morality, and Politics of Stolen Art in Twentieth Century Poland
Authors: Radzilowski John 
Published: December 2016

Abstract
The article examines the legal, moral, and political contradictions of recovering and repatriating works of art and related objects of cultural significance stolen from Poland and its neighbors during and after World War II. Poland suffered the highest rate of loss of any country occupied by Nazi Germany during the war, but a great deal of art was also taken by the Soviets, for whom art theft was a matter of policy. Art plundered by the Nazis was often re-stolen by the communists. Works were taken from both public and private owners. The losses have been compounded by the policies of postwar governments and public institutions in Poland and other countries, which have often prioritized rather vague public rights and claims for wartime compensation over the rights of individuals. In addition, governments and public institutions have lodged competing claims to specific works of art (of varying degrees of validity) against each other, making a just accounting of wartime losses nearly impossible to achieve.
American Books to the Rescue: The American Library Association (ALA) and the Postwar Restoration of Polish Libraries, 1944–1948
Authors: Sroka Marek 
Published: December 2016

Abstract
The American Library Association (ALA)’s role in the postwar cultural restoration of Polish libraries remains relatively unknown. This article discusses the ALA’s efforts at sharing the works of American cultural and research institutions with war devastated libraries in the context of war losses suffered by Polish libraries. Special attention is given to individual requests for American books and journals as they offer insight into various needs of Polish libraries. The ALA’s collaboration with the Kosciuszko Foundation and the American Book Center for War Devastated Libraries with respect to Polish libraries is also examined.
Paisajes Rituales y Políticos Paracas en el Valle de Chincha, Costa Sur del Perú
Authors: Tantaleán Henry 
Published: December 2016

ResumenEn este artículo se realiza una descripción y análisis de los primeros edificios monumentales, caminos, geoglifos y canales de irrigación del valle de Chincha, costa sur del Perú, como un conjunto de rasgos producto de la construcción de un paisaje ritual y político. Se plantea que los edificios monumentales del periodo Paracas tardío (400–100 a.C.) fueron puntos de llegada, encuentro y salida de grupos humanos muy bien organizados en el territorio. Para organizar y dirigir los movimientos sociales hacia esta arquitectura, las elites que dirigieron la construcción de estos rasgos en el paisaje utilizaron su conocimiento del movimiento del sol durante el año, especialmente, durante los solsticios y equinoccios.
AlN and AlGaN layers grown on Si(111) substrate by mixed-source hydride vapor phase epitaxy method
Authors: Jeon Hunsoo , Jeon Injun , Lee Gang Seok , Bae Sung Geun , Ahn Hyung Soo , Yang Min , Yi Sam Nyung , Yu Young Moon , Honda Yoshio , Sawaki Nobuhiko , Kim Suck-Whan 
Published: December 2016

Abstract
High Al-composition AlGaN and AlN epilayers were grown directly on Si(111) substrate by a hydride vapor phase epitaxy (HVPE) method with a melted mixed source in a graphite boat set in a source zone with high temperatures of T = 700 and 800 °C, respectively. The presence of the Ga material in the mixed source of Ga and Al promoted the growth of AlN and AlGaN epilayers in the growth zone. When the temperature in the source zone was 800 °C, the crystalline quality of the AlN and AlGaN epilayers increased as the ratio of Ga to Al increased, and the optimum mix ratio of Ga to Al for the growth of AlN epilayers was approximately 0.35–0.42, obtained from a numerical fitting analysis of the X-ray diffraction (XRD) data for these epilayers. It appears that they can be grown directly by our melted-mixed-source HVPE method in a high-temperature source zone.
An Earth's Future Special Collection: Impacts of the coastal dynamics of sea level rise on low‐gradient coastal landscapes
Authors: Kidwell David M. , Dietrich J. Casey , Hagen Scott C. , Medeiros Stephen C. 
Published: December 2016

AbstractRising sea level represents a significant threat to coastal communities and ecosystems, including altered habitats and increased vulnerability to coastal storms and recurrent inundation. This threat is exemplified in the northern Gulf of Mexico, where low topography, marshes, and a prevalence of tropical storms have resulted in extensive coastal impacts. The ability to facilitate adaptation and mitigation measures relies, in part, on the development of robust predictive capabilities that incorporate complex biological processes with physical dynamics. Initiated in 2010, the 6‐year Ecological Effects of Sea Level Rise—Northern Gulf of Mexico project applied a transdisciplinary science approach to develop a suite of integrated modeling platforms informed by empirical data that are capable of evaluating a range of climate change scenarios. This special issue highlights resultant integrated models focused on tidal hydrodynamics, shoreline morphology, oyster ecology, coastal wetland vulnerability, and storm surges that demonstrate the need for dynamic models to incorporate feedbacks among physical and biological processes in assessments of sea level rise effects on coastal systems. Effects are projected to be significant, spatially variable and nonlinear relative to sea level rise rates. Scenarios of higher sea level rise rates are projected to exceed thresholds of wetland sustainability, and many regions will experience enhanced storm surges. Influenced by an extensive collaborative stakeholder engagement process, these assessments on the coastal dynamics of sea level rise provide a strong foundation for resilience measures in the northern Gulf of Mexico and a transferable approach for application to other coastal regions throughout the world.
Evaluating models of Coulomb stress transfer: Is variable fault geometry important?
Authors: Mildon Zoe K. , Toda Shinji , Faure Walker Joanna P. , Roberts Gerald P. 
Published: December 2016

AbstractTo determine the importance of receiver fault geometry in Coulomb stress calculations a new methodology is presented to model faults with variable geometry. Although most models use planar faults, it is known that these are inaccurate representations of faults observed in the field. The central Italian Apennines are chosen as a straightforward tectonic system with well‐exposed normal faults to investigate the effect of variable geometry. It is shown that the static Coulomb stress transfer is most sensitive to changes in strike of the receiver faults, rather than changes in dip and rake. Therefore, a novel methodology to generate strike‐variable faults composed of discrete rectangular patches is developed. Using the 2009 L'Aquila earthquake (Mw = 6.3) the calculated stress transferred to planar versus variable faults is assessed. The stress transferred to variable faults is sufficiently different when compared to planar cases to merit other earthquake sequences being reassessed with available fault geometry.
The relationship between the Guinea Highlands and the West African offshore rainfall maximum
Authors: Hamilton H. L. , Young G. S. , Evans J. L. , Fuentes J. D. , Núñez Ocasio K. M. 
Published: December 2016

AbstractSatellite rainfall estimates reveal a consistent rainfall maximum off the West African coast during the monsoon season. An analysis of 16 years of rainfall in the monsoon season is conducted to explore the drivers of such copious amounts of rainfall. Composites of daily rainfall and midlevel meridional winds centered on the days with maximum rainfall show that the day with the heaviest rainfall follows the strongest midlevel northerlies but coincides with peak low‐level moisture convergence. Rain type composites show that convective rain dominates the study region. The dominant contribution to the offshore rainfall maximum is convective development driven by the enhancement of upslope winds near the Guinea Highlands. The enhancement in the upslope flow is closely related to African easterly waves propagating off the continent that generate low‐level cyclonic vorticity and convergence. Numerical simulations reproduce the observed rainfall maximum and indicate that it weakens if the African topography is reduced.
Understanding time scales of diffusive fluxes and the implication for steady state and steady shape conditions
Authors: Jazaei Farhad , Simpson Matthew J. , Clement T. Prabhakar 
Published: December 2016

AbstractThe diffusion equation is one of the most commonly used models for describing environmental problems involving heat, solute, and water transport. A diffusive system can be either transient or steady state. When a system is transient, the dependent variable (e.g., temperature, concentration, or hydraulic head) varies with time; whereas at steady state, the temporal variations are negligible. Here we consider an intermediate state, called steady shape, corresponding to the situation where temporal variations in diffusive fluxes are negligible but the dependent variable may remain transient. We present a general theoretical framework for identifying steady shape conditions and propose a novel method for evaluating the time scale needed for a diffusive system to approach both steady shape and steady state conditions.
A comprehensive suite of suprathermal ion sensors
Authors: Allegrini F. , Ho G. C. , Desai M. I. , Ebert R. W. , Nelson K. , Ogasawara K. 
Published: December 2016

AbstractIons with energies from a few times the solar wind plasma thermal energy up to hundreds of keV/e are called suprathermal (ST) ions. ST ions are ubiquitous throughout the heliosphere and comprise material from many sources that vary in time and space. ST ions constitute a key source of material for solar energetic particles and other higher‐energy interplanetary particle populations. Measuring the energy spectra and composition (ionic charge and elemental) of ST ions in the heliosphere has proved to be rather difficult. This is because their energy region lies between that sampled by solar wind instruments, which require long integration times to acquire adequate statistics at these energies, and that by the energetic particle instruments, which typically do not extend down into the lower part of the ST regime due to the low‐energy thresholds (~25–50 keV) of solid‐state detectors. We present two novel concepts that, when combined, measure ST ions with high time, mass, and charge state resolution to address these challenges. Both use electrostatic analyzers that essentially serve as spectrographs. They simultaneously select ions over a broad range of energy‐per‐charge (E/q), thus requiring fewer voltage steps to cover the entire energy range. Their sensitivity is large compared to current instruments because each E/q is sampled for a longer period of time while the geometric factor is comparable. We describe the results obtained with laboratory prototypes. We also present a list of potential options for the detector section.
Saturation effects of the lower ionosphere based on two‐dimensional HF heating model
Authors: Cheng Qi , Guo Li‐xin , Li Hui‐min , Li Jiang‐ting 
Published: December 2016

AbstractThis paper presents a two‐dimensional (2‐D) theoretical model of the lower ionospheric heating by high‐frequency (HF) electromagnetic waves. Compared with the traditional one‐dimensional model, we develop the half‐power width of the heating beam into the theoretical formulations, which dictates the 2‐D distribution characteristics of electron temperature and density perturbations; we also introduce the Sodankylä Ion Chemistry (SIC) model. Based on this numerical model, the saturation effect of ionospheric electron temperature and density is investigated, and simulation is performed by heating at a wave frequency of 6 MHz. Results show that because of energy absorption, the electron temperature peaks at 74 km, and the relative increment of electron density peaks at 94 km in the height direction. Conversely, both the maximum perturbations of electron temperature and density appear on the beam center in the horizontal direction. Second, the saturation time of electron temperature initially increases slowly and then rapidly with increased height. Meanwhile, the saturation time of electron density decreases with increased height. In the horizontal aspect, both the saturation time of electron temperature and density are symmetrical at approximately the position of the beam center owing to the initial Gaussian distribution. Electron temperature far from the beam center results in a long saturation time. Conversely, with increased distance from the beam center, the saturation time of electron density decreases.
Typical values of the electric drift E × B/B2 in the inner radiation belt and slot region as determined from Van Allen Probe measurements
Authors: Lejosne Solène , Mozer F. S. 
Published: December 2016

AbstractThe electric drift E × B/B2 plays a fundamental role for the description of plasma flow and particle acceleration. Yet it is not well‐known in the inner belt and slot region because of a lack of reliable in situ measurements. In this article, we present an analysis of the electric drifts measured below L ~ 3 by both Van Allen Probes A and B from September 2012 to December 2014. The objective is to determine the typical components of the equatorial electric drift in both radial and azimuthal directions. The dependences of the components on radial distance, magnetic local time, and geographic longitude are examined. The results from Van Allen Probe A agree with Van Allen Probe B. They show, among other things, a typical corotation lag of the order of 5 to 10% below L ~ 2.6, as well as a slight radial transport of the order of 20 m s−1. The magnetic local time dependence of the electric drift is consistent with that of the ionosphere wind dynamo below L ~ 2 and with that of a solar wind‐driven convection electric field above L ~ 2. A secondary longitudinal dependence of the electric field is also found. Therefore, this work also demonstrates that the instruments on board Van Allen Probes are able to perform accurate measurements of the electric drift below L ~ 3.
Comb layering monitors decompressing and fractionating hydrous mafic magmas in subvolcanic plumbing systems (Fisher Lake, Sierra Nevada, USA)
Authors: McCarthy Anders , Müntener Othmar 
Published: December 2016

AbstractUnderstanding the dynamics of volcanic eruptions requires constraints on the processes of melt extraction in shallow magma reservoirs. This study focuses on the formation of intraplutonic igneous layering known as comb layers and orbicules within the Fisher Lake Pluton, Sierra Nevada. Comb layers are mineralogically and texturally diverse, ranging from plagioclase‐amphibole comb layers to plagioclase‐pyroxene and olivine comb layers. The majority of individual layers are related to the initiation of plagioclase nucleation and growth on preexisting host rocks and remobilized xenoliths. We use simple phase diagrams to illustrate the formation of comb layers through crystal fractionation along conduit walls and xenoliths, with plagioclase as the liquidus phase. Near‐adiabatic ascent of water‐undersaturated melts through the crust will lead to superheating and crystal resorption, which upon saturation of volatiles at shallow depth can induce heterogeneous nucleation of plagioclase. The rarity of orbicules and comb layers worldwide suggests that adiabatic decompression of crystal‐poor, moderately hydrous melts through the crust is rare. Most melts in intermediate/silicic volcanoes crystallize in multiple reservoirs within the crust prior to emplacement at shallow depth as crystal‐bearing melts. Comb layers and orbicules preserve evidence of multiple melt injections where a sequence of texturally and mineralogically similar comb layers and orbicules reflect the timescale of an individual melt pulse. Short timescales on the order of months to years for the growth of these sequences are estimated using experimental plagioclase growth rates and are interpreted as representing the lifetime of a melt injection within a long‐lived, subvolcanic melt extraction zone.
Bidirectional leader development in a preexisting channel as observed in rocket‐triggered lightning flashes
Authors: Qie Xiushu , Pu Yunjiao , Jiang Rubin , Sun Zhuling , Liu Mingyuan , Zhang Hongbo , Li Xun , Lu Gaopeng , Tian Ye 
Published: December 2016

AbstractTwo cases of bidirectional leader, starting almost immediately below a decaying dart or dart‐stepped leader which terminated before reaching the ground, were identified, for the first time, in rocket‐triggered lightning flashes based on high‐speed video, electric field changes, and channel base current, indicating that a bidirectional leader can be excited by a decayed dart leader and propagate in a preexisting discharge channel. The positive end of the bidirectional leader moved upward along the terminated downward dart leader path, and the negative end extended downward along the decayed initial continuous current or preceding stroke path to the ground and culminated in a return stroke. The positive leader propagated with an average speed of 1.3 × 106 m/s and 2.2 × 106 m/s in the two cases, roughly twice as fast as its negative counterpart with speed of 7.8 × 105 m/s and 1.0 × 106 m/s, respectively. The positive end started earlier than the negative end with a preceding time less than 40.3 µs. The bidirectional leader can be regarded as a recoil leader with the positive end retrogressing along a negative leader channel, whose polarity is contrary to the traditional recoil leader with negative leader end retrogressing along an existing positive leader channel. Weak luminosity was continuously observed during the terminated dart leader and bidirectional leader stage, but the channel current was less than the minimum detection capability of 9.3 A.
A study on radiative transfer effects in 3‐D cloudy atmosphere using satellite data
Authors: Okata M. , Nakajima T. , Suzuki K. , Inoue T. , Nakajima T. Y. , Okamoto H. 
Published: December 2016

AbstractThis study evaluates 3‐D cloud effects on the radiation budget with a combined use of active sensor cloud profiling radar/CloudSat and imager Moderate Resolution Imaging Spectroradiometer/Aqua data on the A‐train. An algorithm is devised for constructing 3‐D cloud fields based on satellite‐observed cloud information. The 3‐D cloud fields thus constructed are used to calculate the broadband solar and thermal radiative fluxes with a 3‐D radiative transfer code developed by the authors. The aim of this study is to investigate the effects of cloud morphology on solar radiative transfer in cloudy atmosphere. For this purpose, 3‐D cloud fields are constructed with the new satellite‐based method, to which full 3D‐RT (radiative transfer) simulations are applied. The simulated 3‐D radiation fields are then used to examine and quantify errors of existing typical plane‐parallel approximations, i.e., Plane‐Parallel Approximation, Independent Pixel Approximation and Tilted Independent Pixel Approximation. Such 3D‐RT simulations also serve to address another objective of this study, i.e., to devise an accurate approximation and to characterize the observed specific 3D‐RT effects by the cloud morphology based on knowledge of idealized 3D‐RT effects. We introduce a modified approach based on an optimum value of diffusivity factor to better approximate the radiative fluxes for arbitrary solar zenith angle determined from the results of 3‐D radiative transfer simulations to redeem the overcorrections of these approximations for large solar zenith angles (SZAs). This new approach, called Slant path Independent Pixel Approximation, is found to be better than other approximations when SZA is large for some cloud cases. Based on the SZA dependence of the errors of these approximations relative to 3‐D computations, satellite‐observed real cloud cases are found to fall into either of three types of different morphologies, i.e., isolated cloud type, upper cloud‐roughened type and lower cloud‐roughened type. Such a classification offers a novel insight into error characteristics of the approximations that are interpreted in the context of specific cloud morphology.