bluuebunny/crossref_metadata_2025 huggingface dataset:
Atmospheric Conditions for Advection‐Radiation Fog Over the Western Yellow Sea
Authors: Yang Liu , Liu Jing‐Wu , Ren Zhao‐Peng , Xie Shang‐Ping , Zhang Su‐Ping , Gao Shan‐Hong
Published: May 2018

Advection fog occurs usually when warm and moist air flows over cold sea surface. It is occasionally reported that the fog air temperature falls below sea surface temperature (called here the sea fog with sea surface heating [ssH]) due to longwave radiation cooling at fog top. Using 8‐year buoy observations, this study reveals that about 33% of the time, the advection fog is with ssH in the western Yellow Sea. By synthesizing long‐term observations from meteorological stations, atmospheric soundings, and offshore buoys, this study further investigates the marine atmospheric boundary layer (MABL) structure and atmospheric circulation associated with the ssH sea fog. Composite analysis shows that a local anomalous high pressure favors widespread formation of the ssH sea fog. The subsidence in the high pressure intensifies the thermal and moist stratification between the MABL and free atmosphere through adiabatic warming. The dry air above helps cool the fog layer by enhancing the longwave radiative cooling at the fog top and the vertical mixing beneath, causing air temperature to drop below sea surface temperature. The ratio of sea fog with ssH to total sea fog decreases from spring to summer as the descending motion and MABL stratification both weaken. This study highlights the importance of longwave radiative cooling at the advection fog top and suggests a way to improve sea fog forecast in the Yellow Sea.
Modeling Sedimentation Dynamics of Sediment‐Laden River Intrusions in a Rotationally‐Influenced, Stratified Lake
Authors: Scheu Kara R. , Fong Derek , Monismith Stephen G. , Fringer Oliver B.
Published: May 2018

River inflows are often the dominant source of sediment into a lacustrine system and the extent of sediment transport can be an important indicator of the impact of introduced constituents on an ecosystem. Inflow intrusions, which intrude into the middle of the water column at a depth of neutral buoyancy, can be common in deep, stratified lakes and reservoirs. However, the dynamics and associated sediment transport of these flows have received less attention in the literature compared to surface or underflow plumes. A three‐dimensional hydrodynamic and sediment transport model was used to investigate sediment transport due to inflow intrusions in Pallanza Bay, an embayment within Lake Maggiore, Italy. The model was validated using field observations of inflow intrusions over varying conditions and was then used to simulate a range of realistic scenarios to evaluate sediment transport and deposition from inflow intrusions. The extent of sedimentation across the range of simulated scenarios can be estimated using a simple analytical expression with only a priori known parameters. The expression is a function of the intrusion plume speed and thickness, which are governed by the volume flow rate and the ambient stratification. We utilize the first‐mode wave speed to characterize the ambient stratification in the simplified expression, which eliminates the need to characterize near‐field mixing and entrainment to predict the intrusion depth. While the simple expression gives a reasonable estimate of the sedimentation extent, it does not capture lateral variability in the plume due to effects like lateral spreading and the earth's rotation.
Groundwater Withdrawals Under Drought: Reconciling GRACE and Land Surface Models in the United States High Plains Aquifer
Authors: Nie Wanshu , Zaitchik Benjamin F. , Rodell Matthew , Kumar Sujay V. , Anderson Martha C. , Hain Christopher
Published: May 2018

Advanced Land Surface Models (LSM) offer a powerful tool for studying hydrological variability. Highly managed systems, however, present a challenge for these models, which typically have simplified or incomplete representations of human water use. Here we examine recent groundwater declines in the US High Plains Aquifer (HPA), a region that is heavily utilized for irrigation and that is also affected by episodic drought. To understand observed decline in groundwater and terrestrial water storage during a recent multiyear drought, we modify the Noah‐MP LSM to include a groundwater irrigation scheme. To account for seasonal and interannual variability in active irrigated area, we apply a monthly time‐varying greenness vegetation fraction (GVF) data set within the model. A set of five experiments were performed to study the impact of groundwater irrigation on the simulated hydrological cycle of the HPA and to assess the importance of time‐varying GVF when simulating drought conditions. The results show that including the groundwater irrigation scheme improves model agreement with ALEXI ET data, mascon‐based GRACE TWS data, and depth‐to‐groundwater measurements in the southern HPA, including Texas and Kansas, and that accounting for time‐varying GVF is important for model realism under drought. Results for the HPA in Nebraska are mixed, likely due to the model's weaknesses in representing subsurface hydrology in this region. This study highlights the value of GRACE data sets for model evaluation and development and the potential to advance the dynamic representations of the interactions between human water use and the hydrological cycle.
Reduced Summer Aboveground Productivity in Temperate C3 Grasslands Under Future Climate Regimes
Authors: Obermeier Wolfgang A. , Lehnert Lukas W. , Ivanov Martin A. , Luterbacher Jürg , Bendix Jörg
Published: May 2018

Temperate grasslands play globally an important role, for example, for biodiversity conservation, livestock forage production, and carbon storage. The latter two are primarily controlled by biomass production, which is assumed to decrease with lower amounts and higher variability of precipitation, while increasing air temperature might either foster or suppress biomass production. Additionally, a higher atmospheric CO2 concentration ([CO2]) is supposed to increase biomass productivity either by directly stimulating photosynthesis or indirectly by inducing water savings (CO2 fertilization effect). Consequently, future biomass productivity is controlled by the partially contrasting effects of changing climatic conditions and [CO2], which to date are only marginally understood. This results in high uncertainties of future biomass production and carbon storage estimates. Consequently, this study aims at statistically estimating mid‐21st century grassland aboveground biomass (AGB) based on 18 years of data (1998–2015) from a free air carbon enrichment experiment. We found that lower precipitation totals and a higher precipitation variability reduced AGB. Under drier conditions accompanied by increasing air temperature, AGB further decreased. Here AGB under elevated [CO2] was partly even lower compared to AGB under ambient [CO2], probably because elevated [CO2] reduced evaporative cooling of plants, increasing heat stress. This indicates a higher susceptibility of AGB to increased air temperature under future atmospheric [CO2]. Since climate models for Central Europe project increasing air temperature and decreasing total summer precipitation associated with an increasing variability, our results suggest that grassland summer AGB will be reduced in the future, contradicting the widely expected positive yield anomalies from increasing [CO2].
Statistical Forecasting of Current and Future Circum‐Arctic Ground Temperatures and Active Layer Thickness
Authors: Aalto J. , Karjalainen O. , Hjort J. , Luoto M.
Published: May 2018

Mean annual ground temperature (MAGT) and active layer thickness (ALT) are key to understanding the evolution of the ground thermal state across the Arctic under climate change. Here a statistical modeling approach is presented to forecast current and future circum‐Arctic MAGT and ALT in relation to climatic and local environmental factors, at spatial scales unreachable with contemporary transient modeling. After deploying an ensemble of multiple statistical techniques, distance‐blocked cross validation between observations and predictions suggested excellent and reasonable transferability of the MAGT and ALT models, respectively. The MAGT forecasts indicated currently suitable conditions for permafrost to prevail over an area of 15.1 ± 2.8 × 106 km2. This extent is likely to dramatically contract in the future, as the results showed consistent, but region‐specific, changes in ground thermal regime due to climate change. The forecasts provide new opportunities to assess future Arctic changes in ground thermal state and biogeochemical feedback.
Traveling Ultralow‐Frequency Waves and Their Influences Over Low‐Energy, Charged Particles
Authors: Yang Mu , Zhou Xu‐Zhi , Zong Qiu‐Gang , Zhang Long‐Fei , Rankin Robert , Wang Yong‐Fu
Published: May 2018

In Earth's magnetosphere, the behavior of charged particles in response to ultralow‐frequency (ULF) waves has long been understood in the framework of their resonant interactions with standing hydromagnetic waves. It has been argued that for impulse‐excited waves, it may take a few wave cycles for the standing structure to be fully established; during these initial cycles, the waves should propagate along magnetic field lines before they are reflected from the ionosphere and are superimposed to form standing waves. However, it has been unclear how particles behave during the initial, traveling stage of the ULF wave evolution. Here we use a simplistic model of ULF wave evolution from traveling to standing waves, to investigate the response of low‐energy electrons (presumably of plasmaspheric and/or ionospheric origin) immediately after the wave excitation. We find that an off‐equatorial spacecraft would observe dispersive signatures in both energy and pitch angle spectra of electron fluxes, and the flux modulation may appear (at specific pitch angle and energy ranges) prior to the electromagnetic oscillations. These predicted signatures, consistent with the scenario of field‐aligned streaming electrons surfing on traveling ULF waves, are indeed observed by the Cluster spacecraft during an ULF wave event on 25 September 2001. Our identification of such signatures, therefore, provides a new understanding of ULF wave evolution and wave‐particle interactions in the inner magnetosphere.
Classifying Precipitation Types in Tropical Cyclones Using the NRL 37 GHz Color Product
Authors: Jiang Haiyan , Zagrodnik Joseph P. , Tao Cheng , Zipser Edward J.
Published: May 2018

The tropical cyclone (TC) webpage developed by the U.S. Naval Research Lab (NRL) has been widely used by the community for real‐time TC monitoring and forecasting. Using 14 years of Tropical Rainfall Measuring Mission Microwave Imager and Precipitation Radar data in TCs, precipitation/convection types are quantitatively classified based on vertical radar profiles corresponding to seven different color regions in the NRL's 37 GHz color composite product. The bright cyan and all pink (including pure pink, bright cyan/pink, and weak cyan/pink, and green/pink) regions are identified as nearly 100% precipitative regions. The bright cyan and pure pink regions are shallow and deep convective precipitation, respectively, while the green/pink, weak cyan/pink, and bright cyan/pink regions are mainly stratiform rain. Eighty‐four percent of pixels in the weak cyan region are precipitating, including either shallow convective, stratiform, or anvil precipitation. Seventy‐six percent of pixels in the green region are nonprecipitating pixels, and 24% of them are very lightly precipitating pixels, which could be contaminated from clouds with high liquid water content. The ability to perform TC precipitation‐type analysis of this detail (convective versus stratiform and deep versus shallow) was previously only possible using radar‐based classification algorithms. Using the 37 GHz precipitation‐type analysis, a significant increase of coverage of stratiform precipitation and shallow convection in the inner core is found between 3 and 21 hr before the onset of TC rapid intensification.
The Far‐UV Albedo of Europa From HST Observations
Authors: Becker T. M. , Retherford K. D. , Roth L. , Hendrix A. R. , McGrath M. A. , Saur J.
Published: May 2018

We present an analysis of Europa's far‐UV spectral albedo using observations during the 1999–2015 time period made by the Space Telescope Imaging Spectrograph on the Hubble Space Telescope. Disk‐integrated observations show that the far‐UV spectrum in the ~130 to 170‐nm range is relatively flat or slightly blue (increasing albedo with decreasing wavelength) for the studied hemispheres: the leading, trailing, and anti‐Jovian hemispheres. At Lyman‐α (121.6 nm), the albedo of the trailing hemisphere continues the blue trend, but it reddens for the leading hemisphere. Also at this wavelength, the albedo of the leading hemisphere, which is higher than the trailing hemisphere at near‐UV and visible wavelengths, is lower than the trailing hemisphere, exhibiting spectral inversion. We find no evidence of a sharp water‐ice absorption edge at 165 nm on any hemisphere of Europa, which is intriguing since such an absorption feature has been observed on the icy Saturnian satellites.
Modifications of Middle Atmosphere Conductivity During Sudden Ionospheric Disturbances Deduced From Changes of Schumann Resonance Peak Frequencies
Authors: Kudintseva I. G. , Galuk Yu. P. , Nickolaenko A. P. , Hayakawa M.
Published: May 2018

This paper presents a novel technique to reveal modifications of the Schumann resonance peak frequencies during sudden ionospheric disturbances (SIDs) caused by the solar X‐ray flares. An SID is associated with the abrupt reduction in ionospheric height over the day hemisphere during solar flares. Reduction of the daytime ionosphere lowers the average height of the Earth‐ionosphere cavity and leads to an increase in its resonant frequencies. An improved profile is used describing the middle atmosphere conductivity and its modification. The resonance frequencies of the Earth‐ionosphere cavity and the characteristic heights of the conductivity profile are computed by the full wave technique for various intensities of ionosphere modifications. Power spectra of the vertical electric field component are calculated using the 2‐dimensional telegraph equations for the uniform spatial distribution of global thunderstorms in the cavity with the day‐night nonuniformity for several observer positions relative to the solar terminator. Changes in the peak frequencies are obtained as a function of magnitude of ionosphere modifications. The weighted average frequency of Schumann resonance is calculated over the first three modes, and the linear fitting is performed for the dependence of this weighted average frequency on the SID intensity and/or on changes in the magnetic characteristic height of the conductivity profile. The data obtained might be used in further interpretations of observational data and in estimating the lower ionosphere modification by using Schumann resonance records.
Shock Connectivity and the Late Cycle 24 Solar Energetic Particle Events in July and September 2017
Authors: Luhmann J. G. , Mays M. L. , Li Yan , Lee C. O. , Bain H. , Odstrcil D. , Mewaldt R. A. , Cohen C. M. S. , Larson D. , Petrie Gordon
Published: May 2018

As solar activity steadily declined toward the cycle 24 minimum in the early months of 2017, the expectation for major solar energetic particle (SEP) events diminished with the sunspot number. It was thus surprising (though not unprecedented) when a new, potentially significant active region rotated around the East limb in early July that by midmonth was producing a series of coronal eruptions, reaching a crescendo around 23 July. This series, apparently associated with the birth of a growing pseudostreamer, produced the largest SEP event(s) seen since the solar maximum years. Activity abated with the decay of the active region, but a second episode of magnetic flux emergence in the same area in early September initiated a new round of eruptions. The western longitude of the erupting region, together with its similar coronal setting in both cases, resulted in a set of nearly homologous multipoint SEP event periods at Earth, Solar TErrestrial RElations Observatory‐A and Mars (Mars Atmosphere and Volatile EvolutioN) for July and September 2017. We use a combination of WSA‐ENLIL‐cone heliospheric simulation results, together with SEPMOD SEP event modeling, to illustrate how the event similarities at the three observer sites can be understood from their relative positions and their connectivities to the generated interplanetary shocks.
Stochastic Rainfall Modeling at Sub‐kilometer Scale
Authors: Benoit Lionel , Allard Denis , Mariethoz Gregoire
Published: May 2018

New measurement devices allow observing rainfall with unprecedented resolution. Such observations often reveal new features of rainfall occurring at the local scale (areas of about 1–25 km2). In particular, the joint effects of the advection of rain storms over the ground, and the deformation of spatial rain patterns along time, generate a complex rain field dependence structure characterized by strong space‐time interactions. When a high‐resolution is desired, stochastic rainfall models must therefore be upgraded to account for these new features of rain fields. In this paper, we propose to improve the meta‐Gaussian framework, which is typically used to model space‐time rain fields, to the specific case of sub‐kilometer rainfall. Particular attention is paid to the reproduction of the main features of local scale rainfall, namely: (1) a skewed distribution of rain intensities with the presence of intraevent intermittency and (2) a space‐time dependency structure with strong and complex space‐time interactions. The resulting model, able to generate high‐resolution, continuous and space‐time rain fields at the local scale, is validated and applied to a real data set collected by a network of drop‐counting rain gauges recording rainfall at a 1 min frequency. The combination of these data with the proposed model results in a complete framework that allows resolving the features of high‐resolution rainfall (1 min temporal resolution, 100 m spatial resolution) over a small alpine catchment in Switzerland.
Fludarabine and neurotoxicity in engineered T-cell therapy
Authors: Lowe Kate L. , Mackall Crystal L. , Norry Elliot , Amado Rafael , Jakobsen Bent K. , Binder Gwendolyn
Published: May 2018

Adoptive T-cell therapy, incorporating engineered T cell receptors (TCRs) or chimeric antigen receptors (CARs), target tumor antigens with high affinity and specificity. To increase the potency of adoptively transferred T cells, patients are conditioned with lymphodepleting chemotherapy regimens prior to adoptive T-cell transfer (ACT), and data suggest that fludarabine is an important component of an effective regimen. In a recent clinical trial using CAR-T cells engineered to target the CD19 B-cell antigen to treat acute lymphoblastic leukemia, JCAR-015 (NCT02535364), two patient deaths due to cerebral edema led to trial suspension. The lymphodepleting agent fludarabine was suggested as the causative agent, in part due to its known association with neurotoxicity and its ability to induce greater potency. In a similar CAR-T study also incorporating fludarabine in the preconditioning regimen, ZUMA-1 (NCT02348216), one patient died of cerebral edema. However, subsequent deaths in the JCAR-015 study after removal of fludarabine and improved understanding behind the mechanisms of CAR-T-related encephalopathy syndrome (CRES) indicate that fludarabine is not the primary causative agent of cerebral edema and that it can be safely incorporated into the preconditioning regimen for ACT. Since entering clinical use in the late 1980s as a chemotherapy agent, fludarabine and similar analogs have been associated with lethal neurological toxicity, yet the manifestation and timing of symptoms are distinct to those observed recently in ACT. Herein, we review the history of fludarabine development as a chemotherapeutic agent, and discuss the safety of its continued use in preconditioning regimens for ACT.
1H NMR, 1H–1H 2D TOCSY and GC-MS analyses for the identification of olive oil in Early Bronze Age pottery from Castelluccio (Noto, Italy)
Authors: Tanasi Davide , Greco Enrico , Noor Radwan Ebna , Feola Stephanie , Kumar Vasantha , Crispino Anita , Gelis Ioannis
Published: May 2018

The development of analytical research in recent decades, at the edge between analytical chemistry and archaeology, provides new methods for the study of organic residues that are usually highly sensitive to natural decay.
Effect of conformational flexibility on photophysics of bis-coumarins
Authors: Kielesiński Łukasz , Gryko Daniel T. , Sobolewski Andrzej L. , Morawski Olaf W.
Published: May 2018

The fluorescence of bis-coumarins linked via CONH and COO functionalities is strongly dependant on solvent polarity.
Influence of Cu adatoms on the molecular assembly of 4,4′-bipyridine on Cu(111)
Authors: Dubois M.-A. , Guillermet O. , Gauthier S. , Zhan G. , Makoudi Y. , Palmino F. , Bouju X. , Rochefort A.
Published: May 2018

The formation of highly organized structures based on two ligands with pyridyl functionalities, 4,4′-bipyridine (BPY) and 1,4-di(4,4′′-pyridyl) benzene (BPYB), and Cu adatoms on the Cu(111) surface has been studied with low temperature and variable temperature scanning tunneling microscopy (STM) and first-principles calculations.
Carbon-supported perovskite-like CsCuCl3 nanoparticles: a highly active and cost-effective heterogeneous catalyst for the hydrochlorination of acetylene to vinyl chloride
Authors: Zhai Yuanyuan , Zhao Jia , Di Xiaoxia , Di Shuxia , Wang Bolin , Yue Yuxue , Sheng Gangfeng , Lai Huixia , Guo Lingling , Wang Hong , Li Xiaonian
Published: May 2018

Non-mercuric catalysts in acetylene hydrochlorination reaction have been gained much attention.
Synthesis, PtS-type structure, and anomalous mechanics of the Cd(CN)2 precursor Cd(NH3)2[Cd(CN)4]
Authors: Coates Chloe S. , Makepeace Joshua W. , Seel Andrew G. , Baise Mia , Slater Ben , Goodwin Andrew L.
Published: May 2018

We report the nonaqueous synthesis of Cd(CN)2 by oxidation of cadmium metal with Hg(CN)2 in liquid ammonia.
Microfluidic engineering of exosomes: editing cellular messages for precision therapeutics
Authors: Zhu Qingfu , Heon Mikala , Zhao Zheng , He Mei
Published: May 2018

This review examines scientific advancements of microfluidic technology for engineering exosomes and assesses future applications and perspectives in developing precision therapeutics, which can serve the community by identifying potential new research areas or technologies that are urgently needed in precision therapeutics.
The effect of the cobalt and manganese central metal ions on the nonlinear optical properties of tetra(4-propargyloxyphenoxy)phthalocyanines
Authors: Mwanza D. , Louzada M. , Britton J. , Sekhosana E. , Khene S. , Nyokong T. , Mashazi P.
Published: May 2018

The phthalocyanines were investigated as optical limiters. The paramagnetic complexes were not effective owing to quenching of the excited states.
Ni-core CuO-shell fibers produced by electrospinning and electroplating as efficient photocathode materials for solar water splitting
Authors: Jo Hong-Seok , Kim Min-Woo , Joshi Bhavana , Samuel Edmund , Yoon Hyun , Swihart Mark T. , Yoon Sam S.
Published: May 2018

Photocathodes of CuO coated over Ni nanofiber cores provide dramatically improved performance in photoelectrochemical water splitting, compared to CuO alone.
Ultra-low voltage triggered release of an anti-cancer drug from polypyrrole nanoparticles
Authors: Samanta Devleena , Hosseini-Nassab Niloufar , McCarty Aidan D. , Zare Richard N.
Published: May 2018

Redox-active anti-cancer drugs can be released without compromising their bioactivity from polypyrrole nanoparticles that respond to ultra-low voltages (−75 mV).
A facile method for preparation of uniform polymeric vesicles with tunable size
Authors: Wu Ming , Wang Yingying , Han Yuanyuan , Cui Jie , Jiang Wei
Published: May 2018

A simple yet general cosolvent method which can be used to prepare polymeric vesicles with rather uniform and tunable sizes is reported.
Highly enantioselective synthesis of α-tertiary chiral amino acid derivatives through rhodium-catalyzed asymmetric arylation of cyclic N-sulfonyl α-ketimino esters
Authors: Wang Zheng , Xu Ming-Hua
Published: May 2018

A simple sulfur-olefin ligand promoted Rh-catalyzed highly enantioselective arylation of cyclic α-ketimino esters with arylboronic acids is described.
Scalable syntheses of well-defined pentadecablock bipolymer and quintopolymer
Authors: Carroll Dean R. , Constantinou Anna P. , Stingelin Natalie , Georgiou Theoni K.
Published: May 2018

The one-pot syntheses of two pentadeca-(15)-block methacrylate-based amphiphilic copolymers, specifically a bipolymer (AB)7A and a quintopolymer (ABCDE)3, are being reported using a fast and easy to scale up procedure that does not require any intermediate purification steps.
Selenium dioxide-promoted selective synthesis of mono- and bis-sulfenylindoles
Authors: Thurow Samuel , Penteado Filipe , Perin Gelson , Alves Diego , Santi Claudio , Monti Bonifacio , Schiesser Carl H. , Barcellos Thiago , Lenardão Eder J.
Published: May 2018

Easy access to mono- and bis-sulfenylindoles using the SeO2/I2 system.
Shear-density coupling for a compressible single-component yield-stress fluid
Authors: Gross Markus , Varnik Fathollah
Published: May 2018

Flow behavior of a single-component yield stress fluid is addressed on the hydrodynamic level. The figure shows the growth direction (arrows) and magnitude (color scale) of the most unstable mode. The white area corresponds to the stable regime.
KIC 8553788: A pulsating Algol with an extreme mass ratio
Authors: Liakos A.
Published: May 2018

Context. The present research paper focuses on the eclipsing binary KIC 8553788 which belongs to two different types of binary systems regarding its physical properties. In particular, it is one of the 71 oscillating stars of Algol-type that have been discovered so far and one of the six that have been published based on high-cadence photometric data of theKeplermission. In addition, it is one of the four semi-detached binaries of the group of R CMa-type systems, while its pulsating component has the fourth fastest frequency among theδScuti stars-members of semi-detached binaries. Detailed light curves as well as spectroscopic and pulsation analyses are presented, while possible explanation scenarios for the evolution of the system involving past mass transfer, mass loss, and/or angular momentum loss due to the presence of a tertiary component are discussed.

Aims. The goal of the study is to extract the pulsational characteristics of the oscillating star of the system, to estimate the absolute parameters of its components, and to provide a possible explanation for its extreme evolutionary status.

Methods. Ground-based spectroscopic observations using the 2.3 m “Aristarchos” telescope were obtained and used for the estimation of the spectral type of the primary component and to model the light curves of the system with higher certainty. The short-cadence photometric data provided by theKeplermission were analysed using standard eclipsing binary modelling techniques, while Fourier analysis was applied on their residuals aiming to reveal the properties of the intrinsic oscillations. The resulting photometric model was combined with a published radial velocity curve to obtain accurate absolute parameters for the components of the system.

Results. The results show that the primary component of the system is of A8 spectral type, has a mass of 1.6M⊙, and a radius of 2R⊙. It is a relatively fast pulsator ofδScuti type that oscillates in 89 frequency modes with the dominant one being 58.26 cycles day−1. On the other hand, the secondary component has a mass of only 0.07M⊙, a radius of 1R⊙, and a temperature of 4400 K. In addition, it was found to be magnetically active with migrating cool spots on its surface.

Conclusions. KIC 8553788, according to its geometrical configuration and its pulsational properties, belongs to the group of oscillating stars of Algol type, while according to its very low mass ratio and its relatively short orbital period belongs also to the group of R CMa stars. If confirmed by radial velocity data of the secondary component, the system would have the lowest mass ratio that has ever been found in semi-detached systems and could therefore be considered as one of the most extreme cases.
Metals and dust in the neutral ISM: the Galaxy, Magellanic Clouds, and damped Lyman-α absorbers
Authors: De Cia Annalisa
Published: May 2018

Context. The presence of dust in the neutral interstellar medium (ISM) dramatically changes the metal abundances that we measure. Understanding the metal content in the neutral ISM, and a direct comparison between different environments, has been hampered to date because of the degeneracy to the observed ISM abundances caused by the effects of metallicity, the presence of dust, and nucleosynthesis.

Aims. We study the metal and dust content in the neutral ISM consistently in different environments, and assess the universality of recently discovered sequences of relative abundances. We also intend to assess the validity of [Zn/Fe] as a tracer of dust in the ISM. This has recently been cast into doubt based on observations of stellar abundances, and needs to be addressed before we can safely use it to study the ISM.

Methods. In this letter we present a simple comparison of relative abundances observed in the neutral ISM in the Galaxy, the Magellanic Clouds, and damped Lyman-α absorbers (DLAs). The main novelty in this comparison is the inclusion of the Magellanic Clouds.

Results. The same sequences of relative abundances are valid for the Galaxy, Magellanic Clouds, and DLAs. These sequences are driven by the presence of dust in the ISM and seem “universal”.

Conclusions. The metal and dust properties in the neutral ISM appear to follow a similar behaviour in different environments. This suggests that a dominant fraction of the dust budget is built up from grain growth in the ISM depending of the physical conditions and regardless of the star formation history of the system. In addition, the DLA gas behaves like the neutral ISM, at least from a chemical point of view. Finally, despite the deviations in [Zn/Fe] observed in stellar abundances, [Zn/Fe] is a robust dust tracer in the ISM of different environments, from the Galaxy to DLAs.
L’empreinte piézographique en pratique quotidienne
Authors: ROKHSSI Hasnaa , ABDELKOUI Annissa , MERZOUK Nadia , BENFDIL Faiza
Published: May 2018

L’édentement complet demeure un handicap fréquent
malgré les progrès obtenus par la prévention
bucco-dentaire. La résorption continue de l’os
alvéolaire suite à la perte des dents peut conduire
à des situations cliniques défavorables pour nos
patients. Dans ces cas, la réhabilitation par prothèse
amovible complète constitue pour le praticien un défi
très difficile à relever.

Actuellement, l’utilisation d’implants comme
supports de moyens de rétention complémentaires
est le traitement de choix pour pallier au manque
de stabilité et de rétention des prothèses amovibles
complètes.

Toutefois, l’empreinte piézographique, constitue une
alternative intéressante surtout pour les patients
chez qui le traitement implantaire ne peut être utilisé.
Elle permet de réaliser des prothèses s’intégrant
parfaitement au jeu musculaire fonctionnel liant
anatomie et physiologie, en adaptant la forme
à la fonction.

Ce travail se donne pour objectif de démystifier
cette technique pour la rendre accessible dans
notre pratique quotidienne au plus grand nombre
d’omnipraticiens.
La prothèse complète immédiate
d’usage : difficultés et gestion
Authors: BAGUI Mohssine , FAJRI Leila , BELHAJ Khalifa , EL MOHTARIME Bouabid , MERZOUK Nadia
Published: May 2018

Vu les multiples avantages qu’offre
la réhabilitation prothétique par une prothèse
complète immédiate d’usage, elle demeure
toujours une solution de choix devant l’urgence
esthétique. Cependant cet acte prothétique
reste très délicat à perfectionner puisqu’il
expose plusieurs difficultés à gérer durant toutes
les étapes cliniques. La présence des dents mal
positionnées, toujours très mobiles constitue
le principal problème qui complique toutes
les étapes prothétiques et à qui tous les autres
problèmes sont reliés.
Modeling of a diffusion with aggregation: rigorous derivation and numerical simulation
Authors: Chen Li , Göttlich Simone , Knapp Stephan
Published: May 2018

In this paper, a diffusion-aggregation equation with delta potential is introduced. Based on the global existence and uniform estimates of solutions to the diffusion-aggregation equation, we also provide the rigorous derivation from a stochastic particle system while introducing an intermediate particle system with smooth interaction potential. The theoretical results are compared to numerical simulations relying on suitable discretization schemes for the microscopic and macroscopic level. In particular, the regime switch where the analytic theory fails is numerically analyzed very carefully and allows for a better understanding of the equation.
Effect of soil stabilized by cement on dynamic response of machine foundations
Authors: Al-Wakel Saad , Abdulrasool Ahmed
Published: May 2018

Machine foundations require significant attention from designers. The main goal of the design of machine foundation is to limit the amplitude displacement and not disturb the people who work near the machine. In some cases, if the design of machine foundations does not satisfy the acceptable value of the dynamic response (such as maximum amplitude of displacement), the stabilization of soil under the machine foundation may be used to decrease the amplitude of displacement. This paper outlines effect of stabilized soil under the foundation by cement on the displacement response of machine foundations. Three-dimensional analyses by using finite element method are carried out to investigate the effect of depth of stabilized layer with different percentage of cement content on the dynamic response of the machine foundation. In addition, the effect of area stabilized by cement material on the dynamic response of machine foundation is investigated. The results shown that, the dynamic response of machine foundations generally decreases with increasing the depth of soil layer stabilized with cement. A significant decrease in the displacement of machine foundations is occurred for the stabilized soil layer with a depth of two times of the width of foundation, and the optimum percentage of cement for stabilizing is 6%.
Simulation of bearing capacity of bored piles
Authors: Majeed Ahmed , Haider Olla
Published: May 2018

This study focuses on how one can possibly predict the ultimate load for the piles that did not reach failure. This challenge was acquired through Chin- Konder method by which, the estimated settlement that correspond to failure load is well defined. Hence, this research aims to make a comparative study between the results of pile load tests carried out in Al-Basrah sewage treatment plant project, and those results induced from the numerical analysis in term of ultimate pile capacity. Consequently, it may give a clear idea on the ability of numerical simulation in getting close to the actual behavior of piles. In the current study, a numerical study using Plaxis 3D Foundation program has been performed on bored piles by the assistance of site investigations of soil. Mohr- Coulomb and linear elastic models were adopted in the simulation for soil and pile respectively. Ten bored piles were used in this analysis under different values of loading. The diameter and length of pile are 0.6m and 24m respectively. The test results indicate that, an excellent agreement has been found as a response of pile capacity between the field and numerical studies. Also, ideal load- settlement curves were created using Chin- Konder method to predict the failure load of bored piles. Also, the results have demonstrated that, the pile capacity obtained from the simulation process is larger about 51% than that design load estimated before the design of piles. This may present a priority to use the finite element method to be accounted as an effective approach in the primary analysis.
Decrease in failure load of inclined driven piles by using Allpile program
Authors: Al-Gharbawi Ahmed
Published: May 2018

One of the problems in construction piles in field is driven inclined which maybe become by error during putting pile or driven. This type of problem in construction is difficult to determine bearing capacity. In this research, studying the determination of bearing capacity of inclined pile in deferent angles and different types of soil as well as deferent types of piles shapes by using AllPile program. The results demonstrate that the reduction in bearing capacity of 30° inclined pile less than 20% from the non inclined pile.
Studying of the combined salts effect on the engineering properties of clayey soil
Authors: Al-Obaidi Anwar , Ihssan Alaa , Allawi Hamed
Published: May 2018

In recent years, a number of studies had been performed to investigate the effect of pore water chemistry on the strength and compressibility characteristics of soil. Although the effect of chloride and sulfates salts separately in pore fluids on the geotechnical properties of soil seems to be well understood, but the influence of combined effect of sulfates and chlorides in pore water on the behavior of soil is still unclear mostly due to the limited numbers of studies as well as the complexity of processes that may occur in soil (with the presence of salts) in pore water-soil interaction. Southern regions of Iraq, especially Basra suffers from low water levels in the summer season in addition to the lack of rain water, which causes a significant increase of salt in the Shatt al Arab. Water salinity continues to increase with time. To investigate the combined impacts of water salinity on the behavior of clayey soils, the basic characteristics of the soil brought from Al-Nahrawan site was studied. Chemical methods were done with three types of water (distilled, water of highly saline as Shatt Al-Arab water and water of Tarmiya as moderate saline water). The effect of water salinity on the geotechnical properties of fine grain soil was investigated. Different laboratory tests such as Atterberg limits, standard compaction, consolidation and shear strength of soil .Results showed that the presence of perceptible amounts of dissolved salts in water can lead to changes in the engineering properties of the soil.
Stability analysis of roadway embankments supported by stone columns with the presence of water table under short-term and long-term conditions
Authors: Kadhim Shaymaa Tareq , Fouad Ziad Bashar
Published: May 2018

Use of stone column technique to improve soft foundation soils under roadway embankments has proven to increase the bearing capacity and reduce the potential settlement. The potential contribution of stone columns to the stability of roadway embankments against general (i.e. deep-seated) failure needs to be thoroughly investigated. Therefore, a two-dimensional finite difference model implemented by FLAC/SLOPE 7.0 software, was employed in this study to assess the stability of a roadway embankment fill built on a soft soil deposit improved by stone column technique. The stability factor of safety was obtained numerically under both short-term and long-term conditions with the presence of water table. Two methods were adopted to convert the three-dimensional model into plane strain condition: column wall and equivalent improved ground methods. The effect of various parameters was studied to evaluate their influence on the factor of safety against embankment instability. For instance, the column diameter, columns’ spacing, soft soil properties for short-term and long-term conditions, and the height and friction angle of the embankment fill. The results of this study are developed in several design charts.
Compressibility of soft Iraqi soil stabilized with traditional Iraqi stabilizers (cement and lime)
Authors: Baqir Husam , Al-Adili Aqeel , Sharef Ali
Published: May 2018

This study shows an improvement of two types of clay soil brought from different parts of Iraq. The first soil (A) from Al - Zaafaraniya site in Baghdad governorate. The second soil (B) from Garma Ali site in the Al Basra governorate, Iraq. Soft clayey soils were treated by a combination of sulphate resistance Portland cement (PC) and Quicklime (LQ) to modify and stability. PC was added in percentages of 2,4,6,8 and 10%, as well as, LQ was added to 2 and 4%, of dry weight. Laboratory tests to determine specific gravity, Atterbergs limits and standard proctor test were conducted. Also, the main objective of this research is the concentrating on compression ratio (CR), the Rebound (Swelling) ratio (RR) and the stiffness during the modulus of elasticity (Es) for treated and natural soils procreation from consolidation test. The results from laboratory tests shows high ability on the enhancing in terms of reduction in plasticity index (greatly increased workability), reduction in compression ratio (CR), reduction in the Rebound (Swelling) ratio (RR), increase in the modulus of elasticity (Es). The change in moisture-density relationships resulting in lower maximum dry densities, higher optimum water content, and less variation of dry density from the maximum over a much wider range of water contents.
Favorable of grouted micropiles for the load transfer in weak sandy soils
Authors: Al-Obaidi Ahmed , Al-Karawi Ansam
Published: May 2018

Micropiles are defined as small diameter piles, implemented as a cast-in-place replacement or injected grout. Generally assumed with a diameter less than 300 mm. The axial capacity of micropiles develops primarily through the bond between gravity grouted (Type A) or post grouted (Type B, C or D) and soil in bonded zone of the micropile. Because of this, micropiles are useful in a variety of applications. Micropiles (Type D) indicate a two-step process of grouting, neat cement grout is placed under gravity head, then, additional grout is injected via a sleeved grout pipe at a specified pressure. In this research, a numerical model was developed to simulate the properties of the micropile (Type D), in addition to micropile (Type A). A general finite element program ABAQUS was selected for the numerical analysis method and for generating the solution. The parameters that affect the load transfer and ultimate capacity of the micropile foundation, which includes micropile length, diameter, grouted length and weak soil type, were investigated. The main results show that the pressure grouting micropile provides better load transfer mechanism as it makes surrounding soil strength to be fully mobilized upon axial loading. Micropiles (Type D)show more favorable in a capacity where the increment range is up to 50% as compared with groundgrouted micropiles (Type A). In addition, the results indicate that the ultimate capacity of micropile increases as the grouted length increases.
Behavior of a strip footing on reinforced soil subjected to inclined load
Authors: Abbas Jawdat
Published: May 2018

This study investigates the behavior of a strip footing under inclined load on reinforced sandy soil by using experimental model. The effect of the load inclination angle (α), number of geogrid layers (N) and the relative density (RD) on the bearing capacity, settlement and horizontal displacement were studied. The results showed that by increasing the number of reinforcement layers (N), the bearing capacity increased, but there is an optimum value (N=4-5) depending on relative density of supporting soil. Also the settlement and horizontal displacement of footing decreasing with increase number of reinforcement layers.
Three-dimensional analysis for piled raft machine foundation embedded in sand
Authors: Mahmood Mahmood , Al-Wakel Saad , Abdulwahhab Ihab
Published: May 2018

Three-dimensional analysis for the dynamic response of a piled raft foundation subjected to vertical vibration is presented in this study. The analysis considers several factors affecting the amplitude of displacement for deep foundation such as pile cap embedment, pile cap thickness, relative density of the sand and the boundary effect. A validation for an experimental piled raft model depending on a scale factor of (20) using at (Plaxis 3D) computer program was performed. The sand is simulated using Mohr-Coloumb model while the concrete is simulated as linear elastic material. It has been found that embedding the pile cap in the soil and increasing its thickness lead to decrease the maximum amplitude of displacement. Furthermore, the predictions showed that increasing the distance between the foundation and the boundaries and increasing the relative density of the sand can significantly minimize the dynamic response of the foundation.
Toward converting some individual parks into smart parks in Kerbela city
Authors: Al-Jameel Hamid Athab
Published: May 2018

The city of Kerbela is from the famous holy cities in Iraq and in the world where the holy shrine of Imam Hussein there. This city suffers from lack of suitable parking area for the vehicles coming to this city. This study selects a surrounding section which is approximately the same as other sections surrounding the city center. Knowing the problems in this section give a comprehensive picture for parking problems in the whole city. The study area has serious parking problems; therefore five off-street parks have been surveyed for two days during ordinary day and the other one in religious day (Thursday at day and night). Other types of data have been collected such as vehicular flow and pedestrian flow in order to select the best management for this area. The location of these five parks is on the north side of the city facing the main arterial street surrounding the holy city and in the opposing direction to the main garage called Al-Garage Al-Muhad from which different trips end and start. The analysis results of field data show that parking behavior differs in the ordinary day from the day of religious issues. It is a specific location has been assigned for one park with multi-stories in the same area as alternative of these separated parks. In addition, it was found that there is a need for managing pedestrian movement related to the parking vehicles in this area. This study also suggests using smart parking system as first step towards building intelligent transportation system to manage the parking facilities.
Effect of curing age on the self-sensing behavior of carbon-based engineered cementitious composites (ECC) under monotonic flexural loading scenario
Authors: Al-Dahawi Ali Majeed
Published: May 2018

The potential effects of curing age on the self-sensing (piezoresistivity) capability of carbon-based Engineered Cementitious Composites (ECC) specimens are under focus in the present study. This non-structural feature can be regarded as one of the best solutions for continuously monitoring of infrastructures in terms of damage and deformations. Carbon fibers which are a micro-scale electrically conductive material were added to the ECC matrix and well dispersed to create the electrically conductive network. This network is responsible for sensing the applied loads on the prismatic specimens. The self-sensing behavior of electrically conductive prismatic specimens under four-point monotonic flexural loading was investigated and compared with dielectric ECC specimens at four ages of curing (7, 28, 90 and 180 days). The results showed that the developed multifunctional cementitious composites can sense the changes in the applied flexural stresses and the resultant mid-span deflection along the adopted curing ages with an improvement in the later ages.