bluuebunny/crossref_metadata_2025_split huggingface dataset:
Effet de la vitesse d’écoulement sur la dynamique de transport des microparticules dans des lits de sable et de gravier
Authors: Mesticou Zyed , Kacem Mariem 
Published: March 2019

In this study, columns experiments are performed to investigate the effects of the flow velocity on the dynamics of particle transport at the micrometric scale (11µm in diameter) through porous media with various particle sizes under saturated conditions. A comparative study is conducted to characterize the influence of grain shape of the porous media on the critical velocity. Various flows are applied by considering porous bed with fine and coarse size grading at the aim to highlight the effect of the ratio of particle size to that of the grains. The experimental results show a decrease of the retention rate of particle with the increase of the velocity for both materials: sand and gravel. The dynamics of deposit differs with a progressive saturation of the retention sites in the case of the fine media, which increases with the increase of the flow velocity and results from it a decrease of the deposit kinetics. In opposite, the saturation of the retention sites is less fast with a constant retention rate because of the heterogeneity of the grains size despite a similar porosity.
Dans cette étude, des essais de colonnes sont conduits pour investiguer les effets de la vitesse de l’écoulement sur la dynamique de transport des particules à l’échelle micrométrique (diamètre moyen 11 µm) à travers des milieux poreux à différentes tailles granulométriques sous des conditions saturées. Une étude comparative de l’influence de la forme des grains du milieu poreux sur l’effet de la vitesse critique est réalisée. Différents débits sont appliqués en prenant en considération un milieu à granulométries fine et grossière dans l’objectif de mettre en évidence l’effet du rapport de tailles des particules et des grains. Les résultats expérimentaux montrent une diminution du taux de rétention de particule avec l’augmentation de la vitesse pour les deux milieux : sable et gravier. La dynamique de dépôt diffère avec une saturation progressive des sites de rétention dans le cas du milieu fin, un comportement qui s’amplifie avec l’augmentation de la vitesse d’écoulement et en résulte une diminution de la cinétique de dépôt. En contrepartie, la cinétique de saturation des sites de rétention est moins rapide en raison de l’hétérogénéité de la taille des grains en dépit d’une porosité similaire.
Physical and optical characteristics of heavily melted “rotten” Arctic sea ice
Authors: Frantz Carie M. , Light Bonnie , Farley Samuel M. , Carpenter Shelly , Lieblappen Ross , Courville Zoe , Orellana Mónica V. , Junge Karen 
Published: March 2019

Abstract. Field investigations of the properties of heavily melted “rotten” Arctic
sea ice were carried out on shorefast and drifting ice off the coast of
Utqiaġvik (formerly Barrow), Alaska, during the melt season. While no
formal criteria exist to qualify when ice becomes rotten, the objective
of this study was to sample melting ice at the point at which its structural and
optical properties are sufficiently advanced beyond the peak of the summer
season. Baseline data on the physical (temperature, salinity, density,
microstructure) and optical (light scattering) properties of shorefast ice
were recorded in May and June 2015. In July of both 2015 and 2017, small
boats were used to access drifting rotten ice within ∼32 km of Utqiaġvik. Measurements showed that pore space increased as ice
temperature increased (−8 to 0 ∘C), ice salinity
decreased (10 to 0 ppt), and bulk density decreased (0.9 to
0.6 g cm−3). Changes in pore space were characterized with thin-section
microphotography and X-ray micro-computed tomography in the laboratory. These
analyses yielded changes in average brine inclusion number density (which
decreased from 32 to 0.01 mm−3), mean pore size (which
increased from 80 µm to 3 mm), and total porosity (increased from
0 % to > 45 %) and structural anisotropy (variable, with
values of generally less than 0.7). Additionally, light-scattering coefficients
of the ice increased from approximately 0.06 to > 0.35 cm−1 as the ice melt progressed. Together, these findings indicate that
the properties of Arctic sea ice at the end of melt season are significantly
distinct from those of often-studied summertime ice. If such rotten ice were
to become more prevalent in a warmer Arctic with longer melt seasons, this
could have implications for the exchange of fluid and heat at the ocean
surface.
Extracting recent short-term glacier velocity evolution over southern Alaska and the Yukon from a large collection of Landsat data
Authors: Altena Bas , Scambos Ted , Fahnestock Mark , Kääb Andreas 
Published: March 2019

Abstract. The measurement of glacier
velocity fields using repeat satellite imagery has become a standard method
of cryospheric research. However, the reliable discovery of important glacier
velocity variations on a large scale is still problematic because time series
span different time intervals and are partly populated with erroneous
velocity estimates. In this study we build upon existing glacier velocity
products from the GoLIVE dataset (https://nsidc.org/data/golive, last
access: 26 February 2019) and compile a multi-temporal stack of velocity data
over the Saint Elias Mountains and vicinity. Each layer has a time separation
of 32 days, making it possible to observe details such as within-season
velocity change over an area of roughly 150 000 km2. Our methodology
is robust as it is based upon a fuzzy voting scheme applied in a discrete
parameter space and thus is able to filter multiple outliers. The
multi-temporal data stack is then smoothed to facilitate interpretation. This
results in a spatiotemporal dataset in which one can identify short-term
glacier dynamics on a regional scale. The goal is not to improve accuracy or
precision but to enhance extraction of the timing and location of ice flow
events such as glacier surges. Our implementation is fully automatic and the
approach is independent of geographical area or satellite system used. We
demonstrate this automatic method on a large glacier area in Alaska and
Canada. Within the Saint Elias and Kluane mountain ranges, several surges and
their propagation characteristics are identified and tracked through time, as
well as more complicated dynamics in the Wrangell Mountains.
Heterogeneity, transient and persistent technical efficiency of Polish crop farms
Authors: Pisulewski Andrzej , Marzec Jerzy 
Published: March 2019

Accounting for heterogeneity in the measurement of farm efficiency is crucial to avoid biases related to climate and soil quality diversity in a given area. Therefore, this paper investigates the level of technical efficiency (TE) of Polish crop farms based on several stochastic frontier panel data models with different approaches to the measurement of unobserved heterogeneity, short- and long- run inefficiency. In our study, we show that ignoring farm heterogeneity can lead to underestimation of the level of TE in conventional stochastic frontier panel data models. Moreover, we have found empirically that not accounting for heterogeneity in the Generalized True Random Effects model may lead to incorrect estimates of persistent TE. The obtained results for Polish crop farms indicate that the level of transient TE (0.81) is lower than the level of persistent TE (0.88). This result suggests that Polish farms may have, for example, problems with adopting new technologies and poor managerial skills.
A taxonomic revision of Globba subsect. Nudae (Zingiberaceae)
Authors: Sangvirotjanapat Sunisa , Denduangboriphant Jessada , Newman Mark F. 
Published: March 2019

Globba subsect. Nudae K.Larsen is revised. Seven species are recognised and three names are lectotypified. A key to the species and descriptions are provided. Three new species are described and illustrated: G. aranyaniae Sangvir. & M.F.Newman sp. nov., G. lithophila Sangvir. & M.F.Newman sp. nov., and G. macrochila Sangvir. & M.F.Newman sp. nov. Four names based on types from Bangladesh, India and Myanmar remain doubtful. The morphological expression of andromonoecy in this group is described in detail. Provisional IUCN conservation assessments of all species are supplied.
Avis de négociation prématuré : l’illusion de la souplesse!
Authors: Nadeau Denis 
Published: March 2019

Déterminer le moment précis où les parties à une convention collective acquièrent le droit de grève ou de lock-out s’avère, vu les nombreuses conséquences juridiques en découlant, de toute première importance.
La Cour d’appel du Québec a récemment bouleversé les règles applicables en la matière en avalisant la légalité de l’envoi d’avis de négociation prématuré. Ce texte vise à démontrer les faiblesses de ce jugement ainsi que les répercussions significatives qu’il peut entraîner au niveau de l’exercice des moyens de pression au Québec.
À quoi oeuvre l’esthétique relationnelle? Une approche transitionnelle du paradigme relationnel en sciences humaines et sociales fondée sur les propositions artistiques de Lygia Clark et Marina Abramović
Authors: Volvey Anne 
Published: March 2019

Nicolas Bourriaud a défini l’esthétique relationnelle de l’art actuel, comme une « esthétique de la proximité » qui opère dans la sphère intersubjective. Sur le fondement des oeuvres des artistes Lygia Clark et Marina Abramović, ce texte complète non seulement le corpus de cet auteur, mais la typologie qu’il a initiée par la « figure » du care, pour la mettre au principe des phénomènes et jugements que cette esthétique décrit. En appui théorique sur la psychanalyse transitionnelle, le texte revient sur l’esthétique relationnelle, mais montre aussi comment elle oeuvre et ce qu’elle fait oeuvrer, mettant en évidence la part non seulement intersubjective, mais haptique (sens et émotion) de la relationnalité ainsi que son horizon narcissique identitaire. Il propose alors une définition paradigmatique de l’esthétique relationnelle, pour la mettre en perspective critique des développements relationnels et esthétiques des sciences humaines et sociales contemporaines, notamment de la géographie, et du tournant spatial.
Effect of the flavonoid baicalin on the proliferative capacity of bovine mammary cells and their ability to regulate oxidative stress
Authors: Perruchot Marie-Hélène , Gondret Florence , Robert Fabrice , Dupuis Emilien , Quesnel Hélène , Dessauge Frédéric 
Published: March 2019

Background
High-yielding dairy cows are prone to oxidative stress due to the high metabolic needs of homeostasis and milk production. Oxidative stress and inflammation are tightly linked; therefore, anti-inflammatory and/or natural antioxidant compounds may help improve mammary cell health. Baicalin, one of the major flavonoids in Scutellaria baicalensis, has natural antioxidant and anti-inflammatory properties in various cell types, but its effects on bovine mammary epithelial cells (BMECs) have not been investigated.

Methods
Explants from bovine mammary glands were collected by biopsy at the peak of lactation (approximately 60 days after the start of lactation) (n = three animals) to isolate BMECs corresponding to mature secretory cells. Cell viability, apoptosis, proliferative capacity and reactive oxygen species (ROS) production by BMECs were measured after increasing doses of baicalin were added to the culture media in the absence or presence of H2O2, which was used as an in vitro model of oxidative stress.

Results
Low doses of baicalin (1–10 µg/mL) had no or only slightly positive effects on the proliferation and viability of BMECs, whereas higher doses (100 or 200 µg/mL) markedly decreased BMEC proliferation. Baicalin decreased apoptosis rate at low concentrations (10 µg/mL) but increased apoptosis at higher doses. ROS production was decreased in BMECs treated with increasing doses of baicalin compared with untreated cells, and this decreased production was associated with increased intracellular concentrations of catalase and NRF-2. Irrespective of the dose, baicalin pretreatment attenuated H2O2-induced ROS production.

Discussion
These results indicate that baicalin exerts protective antioxidant effects on bovine mammary cells. This finding suggests that baicalin could be used to prevent oxidative metabolic disorders in dairy cows.
Scalable Fabrication of Highly Crystalline Organic Semiconductor Thin Film by Channel‐Restricted Screen Printing toward the Low‐Cost Fabrication of High‐Performance Transistor Arrays
Authors: Duan Shuming , Gao Xiong , Wang Yu , Yang Fangxu , Chen Mingxi , Zhang Xiaotao , Ren Xiaochen , Hu Wenping 
Published: March 2019

AbstractControl over the morphology and crystallinity of small‐molecule organic semiconductor (OSC) films is of key importance to enable high‐performance organic optoelectronic devices. However, such control remains particularly challenging for solution‐processed OSC devices because of the complex crystallization kinetics of small‐molecule OSC materials in the dynamic flow of inks. Here, a simple yet effective channel‐restricted screen‐printing method is reported, which uses small‐molecule OSCs/insulating polymer to yield large‐grained small‐molecule OSC thin‐film arrays with good crystallization and preferred orientation. The use of cross‐linked organic polymer banks produces a confinement effect to trigger the outward convective flow at two sides of the channel by the fast solvent evaporation, which imparts the transport of small‐molecule OSC solutes and promotes the growth of small‐molecule OSC crystals parallel to the channel. The small‐molecule OSC thin‐film array produced by screen printing exhibits excellent performance characteristics with an average mobility of 7.94 cm2 V−1 s−1 and a maximum mobility of 12.10 cm2 V−1 s−1, which are on par with its single crystal. Finally, screen printing can be carried out using a flexible substrate, with good performance. These demonstrations bring this robust screen‐printing method closer to industrial application and expand its applicability to various flexible electronics.
Following Nature: Bioinspired Mediation Strategy for Gram‐Positive Bacterial Cells
Authors: Pankratova Galina , Pankratov Dmitry , Milton Ross D. , Minteer Shelley D. , Gorton Lo 
Published: March 2019

AbstractEmployment of redox polymers as mediators is a promising concept to facilitate electron transfer (ET) and improve operational performance of bioelectrochemical systems. Materials science offers a broad range of mediation possibilities; however, their employment so far relies on a trial‐and‐error approach, since there is no comprehensive understanding of the nature of the ET between bacterial cells and redox polymers. In the current work, the polymer–cell interaction is investigated in detail and clear experimental evidence that a redox polymer containing quinone moieties mimicking the natural bacterial charge carriers can be incorporated into the respiratory chain of Gram‐positive Enterococcus faecalis cells and outperform monomeric mediator in ET features is reported. The presented findings disclose the main principles to overcome incompatibilities between abiotic charge carriers and microbial metabolism and provide essential knowledge for further development of mediated microbial bioelectrocatalysis.
Cysteinselektive phosphonamidatbasierte Elektrophile für modulare Biokonjugationen
Authors: Kasper Marc‐André , Glanz Maria , Stengl Andreas , Penkert Martin , Klenk Simon , Sauer Tom , Schumacher Dominik , Helma Jonas , Krause Eberhard , Cardoso M. Cristina , Leonhardt Heinrich , Hackenberger Christian P. R. 
Published: March 2019

AbstractWir beschreiben eine neue Methode zur Proteinsynthese, die das bestehende Repertoire an Möglichkeiten zur Proteinmodifikation erweitert: Eine chemoselektive Reaktion induziert Reaktivität für eine nachfolgende Biokonjugation. Hierbei reagiert ein azidmodifizierter Baustein zunächst mit einem Ethinylphosphonit in einer Staudinger‐Phosphonit‐Reaktion (SPhR) zu einem Ethinylphosphonamidat. Die so entstehende elektronenarme Dreifachbindung modifiziert anschließend in einer cysteinselektiven Reaktion Proteine und Antikörper. Wir zeigen, dass Ethinylphosphonamidate eine herausragende Selektivität für Cysteine aufweisen, gepaart mit einer überragenden Stabilität der Thiol‐Addukte im Vergleich zu klassischen Maleimid‐Konjugaten. Diese Erkenntnis macht unsere Technik zu einer vielseitigen und leistungsstarken Methode für die mühelose Herstellung von stabilen, funktionalen Proteinkonjugaten.
Stable Conversion Chemistry‐Based Lithium Metal Batteries Enabled by Hierarchical Multifunctional Polymer Electrolytes with Near‐Single Ion Conduction
Authors: Zhou Dong , Tkacheva Anastasia , Tang Xiao , Sun Bing , Shanmukaraj Devaraj , Li Peng , Zhang Fan , Armand Michel , Wang Guoxiu 
Published: March 2019

AbstractThe low Coulombic efficiency and serious safety issues resulting from uncontrollable dendrite growth have severely impeded the practical applications of lithium (Li) metal anodes. Herein we report a stable quasi‐solid‐state Li metal battery by employing a hierarchical multifunctional polymer electrolyte (HMPE). This hybrid electrolyte was fabricated via in situ copolymerizing lithium 1‐[3‐(methacryloyloxy)propylsulfonyl]‐1‐(trifluoromethanesulfonyl)imide (LiMTFSI) and pentaerythritol tetraacrylate (PETEA) monomers in traditional liquid electrolyte, which is absorbed in a poly(3,3‐dimethylacrylic acid lithium) (PDAALi)‐coated glass fiber membrane. The well‐designed HMPE simultaneously exhibits high ionic conductivity (2.24×10−3 S cm−1 at 25 °C), near‐single ion conducting behavior (Li ion transference number of 0.75), good mechanical strength and remarkable suppression for Li dendrite growth. More intriguingly, the cation permselective HMPE efficiently prevents the migration of negatively charged iodine (I) species, which provides the as‐developed Li‐I batteries with high capacity and long cycling stability.
Biomimetic synthesis of silver nanoparticles using Syzygium aromaticum (clove) extract: Catalytic and antimicrobial effects
Authors: Ajitha B. , Reddy Y. Ashok Kumar , Lee Yonghee , Kim Min Jun , Ahn Chi Won 
Published: March 2019

In the current work, we followed a green chemistry route to prepare and characterize the silver nanoparticles (AgNPs) using Syzygium aromaticum (clove) extract at room temperature. Suitably, the clove extract acted as a reducing agent as well as a capping agent, and these reactions occurred rapidly. The formation of the AgNPs was confirmed by the observation of the distinct absorption peak at a wavelength of 418 nm using ultraviolet–visible (UV–Vis) spectroscopy, and a morphological study confirmed the uniform distribution of the optimally spherical nanoparticles. Fourier transform infrared spectroscopy (FTIR) results indicated the methoxy and allyl functional groups of eugenol of the clove extract to be responsible for the bioreduction of silver ions and for the stabilization of the resulting nanoparticles (flavonoids). We also found the AgNPs to be effective catalysts of the degradation of three pollutant organic dyes viz., 4‐nitrophenol, methylene blue and rhodamine B, in the presence of excess NaBH4. The antibacterial and antifungal activities of the bio‐synthesized AgNPs were also explored. Overall, the results suggested the potential use of clove extract as a resource for the synthesis of AgNPs having a broad range of possible commercial and biomedical applications.
PBAT/TPS‐nanowhiskers blends preparation and application as food packaging
Authors: da Silva Jania Betania Alves , Santana Jamille Santos , de Almeida Lucas Alessandra , Passador Fabio Roberto , de Sousa Costa Larissa Alves , Pereira Fabiano Vargas , Druzian Janice Izabel 
Published: March 2019

ABSTRACTAbout 85–90% of the market for new materials in biodegradable packaging is served by various blends and composites containing starch in some portion. In an attempt to satisfy the increasing consumer demand, innovative materials are being developed. This includes the concept of active packaging, which, in addition to protecting, interacts with the packaged product. In this context, flexible films have been prepared from blends of poly(butylene adipate‐co‐terephthalate), thermoplastic starch (TPS), and cellulose nanowhiskers (CNW) at different concentrations (0–3.0 wt %) and with distinct compatibilizing agents (glycerol, stearic acid, and citric acid) by flat extrusion. Palm oil was packaged in the films, and was stored under accelerated oxidation conditions as a model system. The films were also used for packing lettuce. The TPS increased the rate of water vapor permeability of the blends. The micrographs showed the films with very porous surface as a function of the CNW concentration. In addition to the antimicrobial action pronounced within 10 days (fungi—molds and yeasts; bacteria—mesophilic and psychrotrophic), the film showed a prooxidant action, indicating its suitability for fruit and vegetable packaging. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019, 136, 47699.
Engineered Targeted Hyaluronic Acid–Glutathione‐Stabilized Gold Nanoclusters/Graphene Oxide–5‐Fluorouracil as a Smart Theranostic Platform for Stimulus‐Controlled Fluorescence Imaging‐Assisted Synergetic Chemo/Phototherapy
Authors: Yang Ying , Wang Shuxin , Wang Chen , Tian Chen , Shen Yuhua , Zhu Manzhou 
Published: March 2019

AbstractA theranostic platform with integrated diagnostic and therapeutic functions as well as specific targeted and controlled combination therapy to enhance treatment efficacy is of great importance for a wide range of biomedical applications. Here, we first attempted to develop biocompatible hyaluronic acid (HA)–glutathione (GSH) conjugate stabilized gold nanoclusters (GNCs) combined with graphene oxide (GO), accompanied by loading 5‐fluorouracil (5FU), as a novel theranostic platform (HG‐GNCs/GO‐5FU, HG refers to HA‐GSH). Multifunctional HG‐GNCs possessed excellent fluorescence, photosensitivity and specific targeting ability to the cancer cells while their fluorescence and singlet oxygen generation could be strongly inhibited by GO and then effectively restored by lysosomal hyaluronidase in tumor cells. The sustained and complete release of 5FU from HG‐GNCs/GO could also be stimulated successively by enzymatic degradation of HA and light‐induced heat effect of GO under laser irradiation so that turn‐on cell imaging‐assisted synergistic therapeutic strategies associated with triple enzyme/light‐controlled chemo/photothermal/photodynamic therapy could be achieved at the same time, reducing greatly the side effects of materials to normal cells. Our study presents a novel strategy to combine targeting and bioimaging with triple therapies to enhance the antitumor effect.