293 research outputs found
Ilmastovaikutusaineisto ruokapalvelusektorille : Aineiston tuottamisen menetelmÀt
Ravintola-alalla on keskeinen rooli kestÀvÀn ruoan kulutuksen edistÀmisessÀ tarjoamalla kestÀviÀ ateriavaihtoehtoja ja muokkaamalla kuluttajien mieltymyksiÀ. EdistÀÀkseen ravintoloiden ilmastotyötÀ Luonnonvarakeskus (Luke) on tuottanut avoimen ilmastovaikutusdatan, joka kattaa yli 1 200 raaka-ainetta. Aineisto on tuotettu elinkaariarvioinnilla (Life Cycle Assessment, LCA), jolloin ilmastovaikutukset kattavat raaka-aineiden elinkaaren aikana syntyneet kasvihuonekaasupÀÀstöt maatalouden tuotantopanosten valmistuksesta aina tukkukauppaan asti. Aineistossa on huomioitu sekÀ kotimainen ettÀ ulkomainen tuotanto, ja julkaistu datasetti sisÀltÀÀ nÀiden ilmastovaikutusten painotetun keskiarvon. Aineisto on lisÀksi yhteensopiva Terveyden ja hyvinvoinnin laitoksen yllÀpitÀmÀn elintarvikkeiden kansallisen koostumustietopankki Finelin kanssa. TÀssÀ raportissa esitetÀÀn datan tuottamiseen kÀytetyt menetelmÀt ja taustat
Nanometer-scale optical imaging of collagen fibers using gold nanoparticles
We describe 3D single particle tracking of gold nanoparticles (AuNPs) moving along collagen fibers in aqueous environment with two-photon excitation conditions. The photoacoustic effect at the collagen fiber caused by the irradiation with ultrashort, near-infrared laser pulses propels the particles adsorbed to the surface of the collagen fibers. We report the tracking of individual AuNPs in three dimensions with high spatial and temporal resolution, of few nanometers and milliseconds, respectively. Due to the emission signal caused by the interaction between the AuNPs and the weak chromophores in the collagen fiber, the trajectories of individual AuNPs reveal the fiber topography with nanometric resolution. The intensity along the trajectory shows that we are sensitive to the distribution of the weak chromophores on the fiber
Rayleigh Imaging of Graphene and Graphene Layers
We investigate graphene and graphene layers on different substrates by
monochromatic and white-light confocal Rayleigh scattering microscopy. The
image contrast depends sensitively on the dielectric properties of the sample
as well as the substrate geometry and can be described quantitatively using the
complex refractive index of bulk graphite. For few layers (<6) the
monochromatic contrast increases linearly with thickness: the samples behave as
a superposition of single sheets which act as independent two dimensional
electron gases. Thus, Rayleigh imaging is a general, simple and quick tool to
identify graphene layers, that is readily combined with Raman scattering, which
provides structural identification.Comment: 8 pages, 9 figure
Disrupting education using smart mobile pedagogies
© Springer Nature Switzerland AG 2019. As mobile technologies become more multifaceted and ubiquitous in society, educational researchers are investigating the use of these technologies in education. A growing body of evidence shows that traditional pedagogies still dominate the educational field and are misaligned with the diverse learning opportunities offered by the use of mobile technologies. There is an imperative to question those traditional notions of education, including how, where and when teaching and learning are enacted, and to explore the possible mediating roles of new mobile technologies. New smart pedagogies, which embrace the affordances offered by mobile technologies, have the potential to disrupt notions of schooling. In this chapter, we examine the nature of smart pedagogies and their intersection with mobile pedagogies. We unpack notions of innovation and disruption. We then discuss smart mobile learning activities for school students identified from a Systematic Literature Review, together with the pedagogical principles underpinning them. We argue to encourage smart pedagogies, teacher educators should support teachers to implement âfeasible disruptionsâ. Consequently, implications for teacher education are explored
Tropospheric emissions: Monitoring of pollution (TEMPO)
TEMPO was selected in 2012 by NASA as the first Earth Venture Instrument, for launch between 2018 and 2021. It will measure atmospheric pollution for greater North America from space using ultraviolet and visible spectroscopy. TEMPO observes from Mexico City, Cuba, and the Bahamas to the Canadian oil sands, and from the Atlantic to the Pacific, hourly and at high spatial resolution (~2.1 km N/SĂ4.4 km E/W at 36.5°N, 100°W). TEMPO provides a tropospheric measurement suite that includes the key elements of tropospheric air pollution chemistry, as well as contributing to carbon cycle knowledge. Measurements are made hourly from geostationary (GEO) orbit, to capture the high variability present in the diurnal cycle of emissions and chemistry that are unobservable from current low-Earth orbit (LEO) satellites that measure once per day. The small product spatial footprint resolves pollution sources at sub-urban scale. Together, this temporal and spatial resolution improves emission inventories, monitors population exposure, and enables effective emission-control strategies. TEMPO takes advantage of a commercial GEO host spacecraft to provide a modest cost mission that measures the spectra required to retrieve ozone (O), nitrogen dioxide (NO), sulfur dioxide (SO), formaldehyde (HCO), glyoxal (CHO), bromine monoxide (BrO), IO (iodine monoxide), water vapor, aerosols, cloud parameters, ultraviolet radiation, and foliage properties. TEMPO thus measures the major elements, directly or by proxy, in the tropospheric O chemistry cycle. Multi-spectral observations provide sensitivity to O in the lowermost troposphere, substantially reducing uncertainty in air quality predictions. TEMPO quantifies and tracks the evolution of aerosol loading. It provides these near-real-time air quality products that will be made publicly available. TEMPO will launch at a prime time to be the North American component of the global geostationary constellation of pollution monitoring together with the European Sentinel-4 (S4) and Korean Geostationary Environment Monitoring Spectrometer (GEMS) instruments.Peer Reviewe
Properties and customization of sensor materials for biomedical applications.
Low-power chemo- and biosensing devices capable of monitoring clinically important parameters in real time represent a great challenge in the analytical field as the issue of sensor calibration pertaining to keeping the response within an accurate calibration domain is particularly significant (1â4). Diagnostics, personal health, and related costs will also benefit from the introduction of sensors technology (5â7). In addition, with the introduction of Registration, Evaluation, Authorization, and Restriction of Chemical Substances (REACH) regulation, unraveling the causeâeffect relationships in epidemiology studies will be of outmost importance to help establish reliable environmental policies aimed at protecting the health of individuals and communities (8â10). For instance, the effect of low concentration of toxic elements is seldom investigated as physicians do not have means to access the data (11)
Detection of X-Ray Polarization from the Blazar 1ES 1959+650 with the Imaging X-Ray Polarimetry Explorer
Observations of linear polarization in the 2-8 keV energy range with the Imaging X-ray Polarimetry Explorer (IXPE) explore the magnetic field geometry and dynamics of the regions generating nonthermal radiation in relativistic jets of blazars. These jets, particularly in blazars whose spectral energy distribution peaks at X-ray energies, emit X-rays via synchrotron radiation from high-energy particles within the jet. IXPE observations of the X-ray-selected BL Lac-type blazar 1ES 1959+650 on 2022 May 3-4 showed a significant linear polarization degree of Î x = 8.0% ± 2.3% at an electric-vector position angle Ï x = 123° ± 8°. However, on 2022 June 9-12, only an upper limit of Î x †5.1% could be derived (at the 99% confidence level). The degree of optical polarization at that time, Î O ⌠5%, is comparable to the X-ray measurement. We investigate possible scenarios for these findings, including temporal and geometrical depolarization effects. Unlike some other X-ray-selected BL Lac objects, there is no significant chromatic dependence of the measured polarization in 1ES 1959+650, and its low X-ray polarization may be attributed to turbulence in the jet flow with dynamical timescales shorter than 1 day
X-Ray Polarization of BL Lacertae in Outburst
We report the first >99% confidence detection of X-ray polarization in BL Lacertae. During a recent X-ray/Îł-ray outburst, a 287 ks observation (2022 November 27-30) was taken using the Imaging X-ray Polarimetry Explorer (IXPE), together with contemporaneous multiwavelength observations from the Neil Gehrels Swift observatory and XMM-Newton in soft X-rays (0.3-10 keV), NuSTAR in hard X-rays (3-70 keV), and optical polarization from the Calar Alto and Perkins Telescope observatories. Our contemporaneous X-ray data suggest that the IXPE energy band is at the crossover between the low- and high-frequency blazar emission humps. The source displays significant variability during the observation, and we measure polarization in three separate time bins. Contemporaneous X-ray spectra allow us to determine the relative contribution from each emission hump. We find >99% confidence X-ray polarization Î 2 - 4 keV = 21.7 â 7.9 + 5.6 % and electric vector polarization angle Ï 2-4keV = â28.°7 ± 8.°7 in the time bin with highest estimated synchrotron flux contribution. We discuss possible implications of our observations, including previous IXPE BL Lacertae pointings, tentatively concluding that synchrotron self-Compton emission dominates over hadronic emission processes during the observed epochs
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