25 results match your criteria: "Institute National de la Recherche Scientifique[Affiliation]"

Quantitative analysis of vessel characteristics at the cellular scale is of great significance for understan-ding plant adaptation strategies to environment. The direct grinding combined with stereo-microscope imaging is one of the main approaches to examine the anatomical structure of xylem (conifer tracheid and hardwood vessel) wood structure, which inevitably damages xylem cells, hindering the accurate understanding of anatomical structures. In this study, we applied X-ray micro-computed tomography (μCT) and stereo-microscope technology to quantitatively measure the diameter and area of vessels of seven Canadian broadleaved tree species (, , , , , , and ).

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Mn-Based Mullites for Environmental and Energy Applications.

Adv Mater

May 2024

Tianjin Key Laboratory of Photo-Electronic Thin Film Device and Technology, College of Electronic Information and Optical Engineering, Nankai University, Tianjin, 300071, China.

Mn-based mullite oxides AMnO (A = lanthanide, Y, Bi) is a novel type of ternary catalyst in terms of their electronic and geometric structures. The coexistence of pyramid Mn-O and octahedral Mn-O makes the d-orbital selectively active toward various catalytic reactions. The alternative edge- and corner-sharing stacking configuration constructs the confined active sites and abundant active oxygen species.

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Hf and Co Dual Single Atoms Co-Doped Carbon Catalyst Enhance the Oxygen Reduction Performance.

Small

June 2024

The Key Laboratory of Fuel Cell Technology of Guangdong Province & The Key Laboratory of New Energy, School of Chemistry and Chemical Engineering, South China University of Technology, Guangzhou, 510641, China.

Single-atom metal-doped M-N-C (M═Fe, Co, Mn, or Ni) catalysts exhibit excellent catalytic activity toward oxygen reduction reactions (ORR). However, their performance still has a large gap considering the demand for their practical applications. This study reports a high-performance dual single-atom doped carbon catalyst (HfCo-N-C), which is prepared by pyrolyzing Co and Hf co-doped ZIF-8 .

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Concave Structural Carbon Co-Doped with Iron Atom Pairs and Nitrogen as Ultra-High Performance Catalyst Toward Oxygen Reduction.

Small

March 2024

The Key Laboratory of Fuel Cell Technology of Guangdong Province School of Chemistry and Chemical Engineering, South China University of Technology, Guangzhou, 510641, P. R. China.

It is crucial to rationally design and synthesize atomic-scale transition metal-doped carbon catalysts with high electrocatalytic activity to achieve a high-efficient oxygen reduction reaction (ORR). Herein, an electrocatalyst comprised of Fe-Fe dual atom pairs and N-doped concave carbon are reported (N-CC@Fe DA) that achieves ultrahigh electrocatalytic ORR activity. The catalyst is prepared by a gaseous doping approach, with zeolitic imidazolate framework-8 (ZIF-8) as the carbon framework precursor and cyclopentadienyliron dicarbonyl dimer as the Fe-Fe atom pair precursor.

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In this study, we present a promising and facile approach toward the fabrication of non-toxic, water-stable, and eco-friendly luminescent fiber paper composed of polycaprolactone (PCL) polymer and CsPbBr@SiO core-shell perovskite nanocrystals. PCL-perovskite fiber paper was fabricated using a conventional electrospinning process. Transmission electron microscopy (TEM) clearly revealed incorporation of CsPbBr@SiO nanocrystals in the fibers, while scanning electron microscopy (SEM) demonstrated that incorporation of CsPbBr@SiO nanocrystals did not affect the surface and diameter of the PCL-perovskite fibers.

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Biomarkers based on resting-state electroencephalography (EEG) signals have emerged as a promising tool in the study of Alzheimer's disease (AD). Recently, a state-of-the-art biomarker was found based on visual inspection of power modulation spectrograms where three "patches" or regions from the modulation spectrogram were proposed and used for AD diagnostics. Here, we propose the use of deep neural networks, in particular convolutional neural networks (CNNs) combined with saliency maps, trained on power modulation spectrogram inputs to find optimal patches in a data-driven manner.

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Metabolic rate and critical thermal maximum estimates for westslope cutthroat trout, .

Conserv Physiol

December 2022

Fisheries and Oceans Canada, Freshwater Institute, Winnipeg Manitoba, R3T 2N6, Canada.

Global warming is changing the thermal habitat of cold-water freshwater fishes, which can lead to decreased fitness and survival and cause shifts in species distributions. The Alberta population of westslope cutthroat trout () is listed as 'Threatened' under the Canadian . The major threats to the species are the alteration in habitat and water flow, competition and hybridization with non-native trout species and climate change.

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Stressor-response functions as a generalizable model for context dependence.

Trends Ecol Evol

December 2022

Central Coast Indigenous Resource Alliance, Campbell River, BC, Canada, V9A 4X1.

Defining the context dependence of ecological states or processes is a fundamental goal of ecology. Stressor-response functions are the quantitative representation of context dependence, where the context (environmental contingency) is defined by location on the stressor (x) axis, and represents a unifying concept in biological science.

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Nanotheranostic agents based on plasmonic nanostructures with their resonance wavelengths located in the second near-infrared window (NIR-II) have gained significant attention in profound tumor photothermal therapy. However, the modulation of localized surface plasmon resonance of gold nanomaterials from the first near-infrared (NIR-I) window to the NIR-II window is still challenging. The structures and compositions of the plasmonic nanomaterials have demonstrated promising characteristics in controlling the optical properties of plasmonic nanostructures.

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Altered Strategies to Inhibit Surface Colonies.

Front Cell Infect Microbiol

November 2021

Infectious Disease Research Laboratory, San Jose, CA, United States.

and infections frequently co-localize in lungs of immunocompromised patients and individuals with cystic fibrosis (CF). The antifungal activity of has been described for its filtrates. Pyoverdine and pyocyanin are the principal antifungal molecules active against biofilm metabolism present in iron-limited or iron-replete planktonic culture filtrates, respectively.

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Digital elevation model (DEM) plays a vital role in hydrological modelling and environmental studies. Many essential layers can be extracted from this land surface information, including slope, aspect, rivers, and curvature. Therefore, DEM quality and accuracy will affect the extracted features and the whole process of modeling.

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Synthesis and optoelectronic properties of Cu3VSe4 nanocrystals.

PLoS One

July 2020

Department of Mechanical and Materials Engineering, Florida International University, College of Engineering and Computing, Miami, Florida, United States of America.

The ternary chalcogenide Cu3VSe4 (CVSe) with sulvanite structure has been theoretically predicted to be a promising candidate for photovoltaic applications due to its suitable bandgap for solar absorption and the relatively earth-abundant elements in its composition. To realize the absorber layer via an inexpensive route, printed thin-films could be fabricated from dispersions of nano-sized Cu3VSe4 precursors. Herein, cubic Cu3VSe4 nanocrystals were successfully synthesized via a hot-injection method.

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Effect of ionic liquid [MIm]HSO on WPCB metal-enriched scraps refined by slurry electrolysis.

Environ Sci Pollut Res Int

November 2019

Key Laboratory of Solid Waste Treatment and Resource Recycle, Ministry of Education, Southwest University of Science and Technology, Mianyang, 621010, China.

Waste printed circuit boards (WPCBs) are usually dismantled, crushed, and sorted to WPCB metal-enriched scraps, still containing an amount of non-metallic materials. This research used slurry electrolysis to refine these WPCB metal-enriched scraps and to examine if a standard ionic liquid, [MIm]HSO, can replace HSO in the system. The impact of the refinement process on metal migration and transformation is discussed in detail.

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Sensitivity analysis of the Pesticide in Water Calculator model for applications in the Pampa region of Argentina.

Sci Total Environ

January 2020

Instituto de Recursos Biológicos, Centro de Investigaciones de Recursos Naturales (CIRN), Instituto Nacional de Tecnología Agropecuaria (INTA), Hurlingham, Buenos Aires, Argentina.

Despite the widespread use of pesticides in the Pampa region of Argentina, mathematical models are rarely employed to predict pesticide fate due to the lack of regionally tested models and the absence of readily available databases to run such models. The objective of the current study was to perform a sensitivity analysis of the Pesticide in Water Calculator (PWC) model for the Pampa Region of Argentina. The sensitivity analysis was performed while simulating applications of 2,4-D (mobile, low Kd) and glyphosate (soil-binding, high Kd) in five localities of the Pampa region: Anguil, Paraná, Marcos Juárez, Pergamino and Tres Arroyos.

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As an indispensable part of printed circuit boards (PCBs), central processing unit (CPU) slots contain a significant amount of precious metals which makes economic sense to recycle these materials. Slurry electrolysis is an attractive approach for electronic waste (e-waste) recycling. In this study, the effect of electrolyte reuse on the recovery of metals (Primarily aluminum, nickel, copper, lead, silver, palladium, platinum and gold), from waste CPU slots by slurry electrolysis is discussed in detail.

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Dual chemosensor for the rapid detection of mercury(ii) pollution and biothiols.

Analyst

August 2019

Queensland University of Technology (QUT), School of Chemistry, Physics and Mechanical Engineering, 2 George street, QLD 4000, Australia.

A new benzothiazole azo dye [(E)-1-((6-methoxybenzo[d]thiazole-2-yl)diazenyl)naphthalene-2,6-diol] (also known as "BAN"), has been synthesised and used as a chemosensor for the rapid and selective detection of mercury(ii) ions in water. The pink coloured chemosensor turns blue when reacted with mercury(ii) ions due to the formation of a 2 : 1 coordination complex. The complex formation causes a bathochromic shift of the chemosensor's UV absorption peak from 540 to 585 nm and turns on a highly selective fluorescence emission at 425 nm.

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Advancing neodymium single-band nanothermometry.

Nanoscale

June 2019

Institute National de la Recherche Scientifique, Centre Énergie Matériaux Télécommunication, Université du Québec, 1650 Boul. Lionel-Boulet, Varennes, Québec J3X 1S2, Canada.

Near-infrared (NIR) emitting contrast agents with integrated optical temperature sensing are highly desirable for a variety of biomedical applications, particularly when subcutaneous target visualization and measurement of its thermodynamic properties are required. To that end, the possibility of using Nd doped LiLuF rare-earth nanoparticles (RENPs) as NIR photoluminescent nanothermometers is explored. These RENPs are relatively small, have narrow size distribution, and can easily be core/shell engineered - all combined, these features meet the requirements of biologically relevant and multifunctional nanoprobes.

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Background: Floods represent a serious threat to human health beyond the immediate risk of drowning. There is few data on the potential link between floods and direct consequences on health such as on cardiovascular health. This study aimed to explore the impact of one of the worst floods in the history of Quebec, Canada on acute cardiovascular diseases (CVD).

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We theoretically and experimentally study the phenomena related to self-phase modulation of Airy pulses in fibers. During nonlinear evolution, most spectral components of the Airy pulses concentrate into one or two peaks for normal and anomalous dispersion, respectively. The resulting peaks self-shift along the propagation, effectively mapping the longitudinal coordinate into the frequency domain.

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We demonstrate theoretically and experimentally that a finite Airy beam changes its trajectory while maintaining its acceleration in nonlinear photorefractive media. During this process, the spatial spectrum reshapes dramatically, leading to negative (or positive) spectral defects on the initial spectral distribution under a self-focusing (or defocusing) nonlinearity.

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The Cotton-Mouton (Voigt) and Faraday effects induce adjustable linear and circular birefringence in optical media with external magnetic fields. We consider these effects as a technique for magneto-optical control of the transmission of bimodal light beams through Kerr-nonlinear crystals. Numerical analysis suggests that a properly applied magnetic field may accelerate, delay, or arrest the collapse of (2+1)D beams.

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Polarization proximity effect in isolator crystal pairs.

Opt Lett

December 2008

Institute National de la Recherche Scientifique, Université du Québec, Varennes, Québec J3X 1S2, Canada.

We experimentally study the polarization dynamics (orientation and ellipticity) of near-infrared light transmitted through magneto-optical yttrium iron garnet isolator crystal pairs using a modified balanced detection scheme. When the pair separation is in the submillimeter range, we observed a proximity effect in which the saturation field is reduced by up to 20%. One-dimensional calculations suggest that the proximity effect originates from magnetostatic interactions between the dipole moments of the isolator crystals.

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We study numerically the trapping dynamics of nonlinear waves scattered by local guiding photonic centers with normal eigenmodes which are embedded in uniform nonlinear Kerr waveguides. The linear and nonlinear scattering from a local defect may be treated from either a wave optics approach or a ray optics approach. The former provides a better understanding of the wave dynamics while the latter enables one to perform quasi-analytical estimates of the extent of trapping in a given structure.

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Observation of discrete gap solitons in binary waveguide arrays.

Opt Lett

December 2004

Institute National de la Recherche Scientifique, Université du Quebec, Varennes, Quebec J3X 1S2, Canada.

We report an experimental study of discrete gap solitons in binary arrays of optical waveguides. We observe self-focusing indicating soliton generation when the inclination angle of an input beam is slightly above the Bragg angle and show that the propagation direction of the emerging gap soliton is influenced by the effect of interband momentum exchange.

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