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ABSTRACTDue to increased copper production and the associated environmental consequences, copper production processes need to be improved, considering the impact of their byproducts, among others slag. This study investigated the leaching of individual constituents of iron silicate slag from a copper smelter. This was done by characterising granulated samples of its constituents – glass, matte, speiss – to determine their leaching contribution. It was observed that leaching in distilled and deionised water without pH regulation achieved various natural pH for the constituents. At natural pH, glass (Cu, Zn) and speiss (Ni, Sb) contributed to leaching. Static pH titrations showed the increased leaching of Zn, Cu, Ni, As, and Sb with decreasing pH. The results showed that, an iron silicate slag consisting of glass, matte and speiss, contributes to leaching as follows: matte – Cu and Ni, speiss – Cu, Ni, As, and Sb. Zn leaching is similar among the constituents.

ABSTRACTWater-granulated CaO-modified iron-silicate slags have shown beneficial properties for cement applications. To further evaluate potential applications, the leaching properties must be understood. Therefore, this study aims to characterise and assess the metal leaching of iron-silicate slags (2.6% CaO) modified with lime (CaO, up to 20 wt.%) produced on both laboratory and industrial scales. The granulated samples showed amorphous contents for the studied CaO range. Generally, the metal content of the samples decreased with the increasing CaO content. Batch leaching tests were conducted on the slags, and the metal leaching and CaO content of the slag were strongly correlated. The leaching of Zn and Cu decreased with the increasing CaO content in the slag. Overall, the slags with 12–13% CaO exhibited minimal leaching of Zn, Cu, Ni, and Sb. These findings indicate that CaO influences the properties of the slag and can suppress metal leaching from water-granulated iron-silicate slags.

Ions in the F region ionosphere at 150–400 km altitude consist mainly of molecular NO+and O2+${\mathrm{O}}_{2}^{+}$, and atomic O+. Incoherent scatter (IS) radars are sensitive to the molecular‐to‐atomic ion density ratio, but its effect to the observed incoherent scatter spectra is almost identical with that of the ion temperature. It is thus very difficult to fit both the ion temperature and the fraction of O+ions to the observed spectra. In this paper, we introduce a novel combination of Bayesian filtering, smoothness priors, and chemistry modeling to solve for F1region O+ion fraction from EISCAT Svalbard IS radar (75.43° corrected geomagnetic latitude) data during the international polar year (IPY) 2007–2008. We find that the fraction of O+ions in the F1region ionosphere is controlled by ion temperature and electron production. The median value of the molecular‐to‐atomic ion transition altitude during IPY varies from 187 km at 16–17 MLT to 208 km at 04–05 MLT. The ion temperature has maxima at 05–06 MLT and 15–16 MLT, but the transition altitude does not follow the ion temperature, because photoionization lowers the transition altitude. A daytime transition altitude maximum is observed in winter, when lack of photoionization leads to very low daytime electron densities. Both ion temperature and the molecular‐to‐atomic ion transition altitude correlate with the Polar Cap North geomagnetic index. The annual medians of the fitted transition altitudes are 14–32 km lower than those predicted by the International Reference Ionosphere. Ions in the F region ionosphere at 150–400 km altitudes consist mainly of molecular NO+and O2+${\mathrm{O}}_{2}^{+}$, and atomic O+. Incoherent scatter radars are sensitive to the molecular‐to‐atomic ion density ratio, but its effect to the observed incoherent scatter spectra is almost identical with that of the ion temperature. It is thus very difficult to fit both the ion temperature and the fraction of O+ions to the observed spectra. This causes bias to the fitted temperatures and leaves behavior of the F1region ion composition poorly known. We apply a novel combination of inverse mathematics and chemistry modeling to analysis of EISCAT Svalbard incoherent scatter radar data, and solve for both the ion temperature and the fraction of O+ions at the same time. We find that the ion composition is considerably different from a standard model, that it undergoes regular diurnal variations, and it is affected by geomagnetic activity. The typical variations can be qualitatively explained by known diurnal variations in ion temperature, solar photoionization, and ion chemistry. When the ionosphere above Svalbard is in almost complete darkness in mid‐winter, ion composition in the daytime ionosphere is considerably different from that observed during the other seasons. We use novel data analysis techniques and chemistry modeling to fit atomic oxygen ion fractions to EISCAT Svalbard radar data during IPYWe characterize the F1 region ion composition dependence on local time, solar zenith angle, and geomagnetic activityThe molecular‐to‐atomic ion transition altitudes are 14–32 km lower than those predicted by the International Reference Ionosphere We use novel data analysis techniques and chemistry modeling to fit atomic oxygen ion fractions to EISCAT Svalbard radar data during IPY We characterize the F1 region ion composition dependence on local time, solar zenith angle, and geomagnetic activity The molecular‐to‐atomic ion transition altitudes are 14–32 km lower than those predicted by the International Reference Ionosphere

The primary focus of this study was the motion of auroral patches and the polarization electric field generated therein observed on 9 November 2015 in an experiment using the European incoherent scatter (EISCAT) radars, Kilpisjärvi Atmospheric Imaging Receiver Array (KAIRA), and an all‐sky imager simultaneously. Based on the all‐sky imager data, the drift speed of the auroral patches corresponded to a southward electric field of 14.1( ± 3.7)–17.2( ± 4.5) mV/m. The convective electric field derived from the EISCAT radars and KAIRA observation was approximately 14.6 mV/m in the southward direction. This suggest that the spatial distribution of the auroral patches reflects the distribution of the cold plasma in the magnetosphere. The electron density and the height‐integrated Hall conductance between 80 and 120 km were enhanced by a factor of 2–4 inside the auroral patches. In this situation, a polarization electric field was generated therein. Enhanced ion velocities due to the polarization electric field was observed at up to 200‐km altitude; however, the absolute values of the ion velocities were approximately 40% of what was expected from the polarization electric field. A field‐aligned current (FAC) from 5 to 10 μA/m−2in the edges of the auroral patches could explain the weakening of the polarization electric field. Since a FAC of that order of magnitude corresponded with that observed by the Swarm satellite, it was suggested that the polarization electric field was weakened by the FAC. Furthermore, the polarization electric field propagated upward from the dynamo region to at least 200 km. The drift speed of auroral patches was consistent with the convective electric fieldThe polarization electric fields perpendicular to the convective electric fields were generated inside the auroral patchesThe upward and downward FACs contacting the west and east side edges of the auroral patches weakened the polarization electric field

The widespread acceptability of mobile devices in present times have caused their applications to be increasingly rich in terms of the functionalities they provide to the end users. Such applications might be very prevalent among users but the execution results in dissipating many of the device end resources. Mobile cloud computing (MCC) has a solution to this problem by offloading certain parts of the application to cloud. At the first place, one might find computation offloading quite promising in terms of saving device end resources but eventually may result in being the other way around if performed in a static manner. Frequent changes in device end resources and computing environment variables may lead to a reduction in the efficiency of offloading techniques and even cause a drop in the quality of service for applications involving the use of real-time information. In order to overcome this problem, the authors propose an adaptive computation offloading framework for data stream applications wherein applications are partitioned dynamically followed by being offloaded depending upon the device end parameters, network conditions, and cloud resources. The article also talks about the proposed algorithm that depicts the workflow of the offloading model. The proposed model is simulated using the CloudSim simulator. In the end, the authors illustrate the working of the proposed system along with the simulated results.

This study investigates the response of the semidiurnal tide (SDT) to the 2013 major sudden stratospheric warming (SSW) event using meteor radar wind observations and mechanistic tidal model simulations. In the model, the background atmosphere is constrained to meteorological fields from the Navy Global Environmental Model—High Altitude analysis system. The solar (thermal) and lunar (gravitational) SDT components are forced by incorporating hourly temperature tendency fields from the ERA5 forecast model, and by specifying the M2and N2lunar gravitational potentials, respectively. The simulated SDT response is compared against meteor wind observations from the CMOR (43.3°N, 80.8°W), Collm (51.3°N, 13.0°E), and Kiruna (67.5°N, 20.1°E) radars, showing close agreement with the observed amplitude and phase variability. Numerical experiments investigate the individual roles of the solar and lunar SDT components in shaping the net SDT response. Further experiments isolate the impact of changing propagation conditions through the zonal mean background atmosphere, non‐linear wave‐wave interactions, and the SSW‐induced stratospheric ozone redistribution. Results indicate that between 80 and 97 km altitude in the northern hemisphere mid‐to‐high latitudes the net SDT response is driven by the solar SDT component, which itself is shaped by changing propagation conditions through the zonal mean background atmosphere and by non‐linear wave‐wave interactions. In addition, it is demonstrated that as a result of the rapidly varying solar SDT during the SSW the contribution of the lunar SDT to the total measured tidal field can be significantly overestimated. Simulations of the semidiurnal tide (SDT) are compared against meteor wind observations in the mid‐to‐high latitude northern hemisphere during the 2013 sudden stratospheric warmingIndividual lunar and solar SDT simulations find that the net tidal response is largely driven by the solar componentThe response of the solar SDT is driven by changing zonal mean propagation conditions and by non‐linear interactions with planetary waves Simulations of the semidiurnal tide (SDT) are compared against meteor wind observations in the mid‐to‐high latitude northern hemisphere during the 2013 sudden stratospheric warming Individual lunar and solar SDT simulations find that the net tidal response is largely driven by the solar component The response of the solar SDT is driven by changing zonal mean propagation conditions and by non‐linear interactions with planetary waves

Differential energy flux of electrons precipitating into the high‐latitude ionosphere can be estimated from incoherent scatter radar observations of the ionospheric electron density profile. We present a method called ELSPEC for electron spectrum estimation from incoherent scatter radar measurements, which is based on integration of the electron continuity equation and spectrum model selection by means of the Akaike information criterion. This approach allows us to use data with almost arbitrary time resolutions, enables spectrum estimation with dense energy grids, avoids noise amplifications in numerical derivatives, and yields statistical error estimates for all the output parameters, including the number and energy fluxes and upward field‐aligned currents carried by the precipitating electrons. The technique is targeted for auroral energies, 1–100 keV, which ionize the atmosphere mainly between 80 and 150 km altitudes. We validate the technique by means of a simulation study, which shows that Maxwellian, kappa, and mono‐energetic spectra, as well as combinations of those, can be reproduced. Comparison study for two conjugate satellite measurements to the EISCAT UHF radar are shown, for Reimei and Swarm, showing an agreement with the results. Finally, an example of a 2‐hr measurement by the EISCAT radar is shown, during which we observe a variety of precipitation characteristics, from soft background precipitation to mono‐energetic spectra with peak energies up to 60 keV. The upward field‐aligned current varies from 0 to 10 μAm−2and the total energy flux from 0 to 250 mWm−2. Electron energy spectra are estimated from incoherent scatter radar measurements by integrating the electron continuity equationEstimates of upward field‐aligned current and auroral power are integrated from the spectrum estimatesThe results are validated using simulations and comparisons with satellite measurements

Dust impact detection by electric field instruments is a relatively new method. However, the influence of dust impacts on electric field measurements is not completely understood and explained. A better understanding is very important for reliable dust impact identification, especially in environments with low dust impact rate. Using data from Earth‐orbiting Magnetospheric Multiscale mission (MMS) spacecraft, we present a study of various pulses detected simultaneously by multiple electric field antennas in the monopole (probe‐to‐spacecraft potential measurement) and dipole (probe‐to‐probe potential measurement) configurations. The study includes data obtained during an impact of a millimeter‐sized object. We show that the identification of dust impacts by a single antenna is a very challenging issue in environments where solitary waves are commonly present and that some pulses can be easily misinterpreted as dust impacts. We used data from multiple antennas to distinguish between changes in the spacecraft potential (dust impact) and structures in the ambient plasma or electric field. Our results indicate that an impact cloud is in some cases able to influence the potential of the electric field antenna during its expansion. Dust impact detection by multiple electric field antennas in the monopole and dipole configurationsSimilarities in signatures of dust impacts and solitary waves are discussedData obtained during the impact of a millimeter‐sized object are described in detail

Using data from the Sodankylä Geophysical Observatory (67°22′N, 26°38′E, Finland) meteor camera from the whole year 2015, we identified and investigated 28 optical meteors with accompanying ionization trails unambiguously detected by the Sodankylä Geophysical Observatory ionosonde, which sounded the ionosphere once per minute with frequency rising from 0.5 to 16 MHz. These ionosonde reflections were obtained from heights around 90 km. The electron line densities of the trails were found to be between 1014and 1016m−1, which characterize the trails as nonunderdense (i.e., transitional and overdense). The ionosonde reflections were observed for a few minutes, with decreasing maximal frequency of the return. During the first 250 s, for the trails with initial line density about (2–3) · 1015m−1the return frequency decreased with time corresponding to the diffusional expansion of cylindrical meteor trails, that is, f∝ t−γ, where the exponent γ= 0.5, whereas less dense trails decayed slower (γ≈ 0.2) and more dense trails decayed faster (γ≈ 1). In many cases the meteor events were accompanied by nonspecular long‐lived detections using a colocated all‐sky interferometric meteor radar with operating frequency 36.9 MHz. As a rule the meteor radar echo durations were longer than expected from diffusional expansion of cylindrical meteor trails and their amplitudes were highly variable. We suggest that the slower frequency decrease of the ionosonde echoes and the nonspecular long‐lived meteor radar echoes might be associated with the presence of meteoric dust. Optical, ionosonde, and meteor radar observations of non‐underdense (transitional and overdense) meteor trails were made at high latitudeDuring the first 4 min the decay rate of ionosonde echo depends on initial electron line density of trails (empirical dependence obtained)Meteor events were accompanied by nonspecular long‐lived detections using a colocated meteor radar with operating frequency 36.9 MHz

Precipitation of energetic particles into the Earth's atmosphere can significantly change the properties, dynamics, as well as the chemical composition of the upper and middle atmosphere. In this paper, using Monte Carlo models, we simulate, from first principles, the interaction of monoenergetic beams of precipitating electrons with the atmosphere, with particular emphasis on the process of bremsstrahlung radiation and its resultant ionization production and atmospheric effects. The pitch angle dependence of the ionization rate profile has been quantified: the altitude of peak ionization rate depends on the pitch angle by a few kilometers. We also demonstrate that the transport of precipitating electron energy in the form of bremsstrahlung photons leads to ionization at altitudes significantly lower than the direct impact ionization, as low as ∼20 km for 1 MeV precipitating electrons. Moreover, chemical modeling results suggest that the chemical effects in the atmosphere due to bremsstrahlung‐induced ionization production during energetic electron precipitation are likely insignificant. The energy and altitude distributions of bremsstrahlung photons produced during electron precipitation have been quantifiedThe ionization rate due to both precipitating electrons and associated bremsstrahlung photons has been calculatedBremsstrahlung‐induced chemical impacts on the atmosphere during realistic electron precipitation are likely insignificant

The plasmas (electrons and ions) in the inner magnetosphere have wide energy ranges from electron volts to mega-electron volts (MeV). These plasmas rotate around the Earth longitudinally due to the gradient and curvature of the geomagnetic field and by the co-rotation motion with timescales from several tens of hours to less than 10 min. They interact with plasma waves at frequencies of mHz to kHz mainly in the equatorial plane of the magnetosphere, obtain energies up to MeV, and are lost into the ionosphere. In order to provide the global distribution and quantitative evaluation of the dynamical variation of these plasmas and waves in the inner magnetosphere, the PWING project (study of dynamical variation of particles and waves in the inner magnetosphere using ground-based network observations, http://www.isee.nagoya-u.ac.jp/dimr/PWING/) has been carried out since April 2016. This paper describes the stations and instrumentation of the PWING project. We operate all-sky airglow/aurora imagers, 64-Hz sampling induction magnetometers, 40-kHz sampling loop antennas, and 64-Hz sampling riometers at eight stations at subauroral latitudes (~ 60° geomagnetic latitude) in the northern hemisphere, as well as 100-Hz sampling EMCCD cameras at three stations. These stations are distributed longitudinally in Canada, Iceland, Finland, Russia, and Alaska to obtain the longitudinal distribution of plasmas and waves in the inner magnetosphere. This PWING longitudinal network has been developed as a part of the ERG (Arase)-ground coordinated observation network. The ERG (Arase) satellite was launched on December 20, 2016, and has been in full operation since March 2017. We will combine these ground network observations with the ERG (Arase) satellite and global modeling studies. These comprehensive datasets will contribute to the investigation of dynamical variation of particles and waves in the inner magnetosphere, which is one of the most important research topics in recent space physics, and the outcome of our research will improve safe and secure use of geospace around the Earth.

AbstractBefore the secretion of hard dental tissues, tooth germs undergo several distinctive stages of development (dental lamina, bud, cap and bell). Every stage is characterized by specific proliferation patterns, which is regulated by various morphogens, growth factors and homeodomain proteins. The role of MSX homeodomain proteins in odontogenesis is rather complex. Expression domains of genes encoding for murine Msx1/2 during development are observed in tissues containing highly proliferative progenitor cells. Arrest of tooth development in Msxknockout mice can be attributed to impaired proliferation of progenitor cells. In Msx1knockout mice, these progenitor cells start to differentiate prematurely as they strongly express cyclin-dependent kinase inhibitor p19INK4d. p19INK4dinduces terminal differentiation of cells by blocking the cell cycle in mitogen-responsive G1 phase. Direct suppression of p19INK4dby Msx1 protein is, therefore, important for maintaining proliferation of progenitor cells at levels required for the normal progression of tooth development. In this study, we examined the expression patterns of MSX1, MSX2 and p19INK4din human incisor tooth germs during the bud, cap and early bell stages of development. The distribution of expression domains of p19INK4dthroughout the investigated period indicates that p19INK4dplays active role during human tooth development. Furthermore, comparison of expression domains of p19INK4dwith those of MSX1, MSX2 and proliferation markers Ki67, Cyclin A2 and pRb, indicates that MSX-mediated regulation of proliferation in human tooth germs might not be executed by the mechanism similar to one described in developing tooth germs of wild-type mouse.

This study investigates the contribution of energetic (E> 30 keV) particle precipitation during a pulsating aurora event over Kilpisjärvi (L= 6.2) on 26 February 2014. It is based on the comparison of auroral blue‐line emission (427.8 nm) data from an all‐sky camera and cosmic noise absorption (CNA) data obtained from a multibeam experiment of the Kilpisjärvi Atmospheric Imaging Receiver Array (KAIRA) riometer. The data sets are compared for three KAIRA beams close to magnetic zenith. Results show a clear correlation between the measured CNA and the auroral blue‐line emission during the event, for each beam. In addition, individual pulsations are observed for the first time in the cosmic noise absorption data measured by KAIRA and are found to be close‐to‐identical to the optical pulsations. This suggests that the modulation of electron precipitation during pulsating aurora takes place in a consistent way over a broad range of energies. Cosmic noise absorption and blue‐line auroral emission are strongly correlated during pulsating aurora eventIndividual pulsations can be detected in cosmic noise absorption data and are consistent with the optical pulsationsPrecipitation of both auroral and energetic electrons was simultaneously modulated during the studied pulsating aurora event

We present the first study of dust impact events on one of the Earth‐orbiting Cluster satellites. The events were identified in the measurements of the wide band data (WBD) instrument on board the satellite operating in monopole configuration. Since 2009 the instrument is operating in this configuration due to the loss of three electric probes and is therefore measuring the potential between the only operating antenna and the spacecraft body. Our study shows that the WBD instrument on Cluster 1 is able to detect pulses generated by dust impacts and discusses four such events. The presence of instrumental effects, intensive natural waves, noncontinuous sampling modes, and the automatic gain control complicates this detection. Due to all these features, we conclude that the Cluster spacecraft are not ideal for dust impact studies. We show that the duration and amplitudes of the pulses recorded by Cluster are similar to pulses detected by STEREO, and the shape of the pulses can be described with the model of the recollection of impact cloud electrons by the positively charged spacecraft. We estimate that the detected impacts were generated by micron‐sized grains with velocities in the order of tens of km/s. The first hypervelocity dust impact detection by the Cluster spacecraftThe concept of dust impact detection with electric field instruments is discussedThe size and velocity of impinging dust grains are estimated

It is well known that auroral patterns at the substorm recovery phase are characterized by diffuse or patch structures with intensity pulsation. According to satellite measurements and simulation studies, the precipitating electrons associated with these aurorae can reach or exceed energies of a few hundreds of keV through resonant wave‐particle interactions in the magnetosphere. However, because of difficulty of simultaneous measurements, the dependency of energetic electron precipitation (EEP) on auroral morphological changes in the mesoscale has not been investigated to date. In order to study this dependency, we have analyzed data from the European Incoherent Scatter (EISCAT) radar, the Kilpisjärvi Atmospheric Imaging Receiver Array (KAIRA) riometer, collocated cameras, ground‐based magnetometers, the Van Allen Probe satellites, Polar Operational Environmental Satellites (POES), and the Antarctic‐Arctic Radiation‐belt (Dynamic) Deposition‐VLF Atmospheric Research Konsortium (AARDDVARK). Here we undertake a detailed examination of two case studies. The selected two events suggest that the highest energy of EEP on those days occurred with auroral patch formation from postmidnight to dawn, coinciding with the substorm onset at local midnight. Measurements of the EISCAT radar showed ionization as low as 65 km altitude, corresponding to EEP with energies of about 500 keV. Aurora is emission of the atmospheric particles excited by electrons coming from the magnetosphere. The electrons have energies of 1–10 keV or higher. In particular, it is known that the energy can increase more than 100 keV in association with the pulsating aurora and that morphology of the pulsating aurora changes with time. However, relationships between the energy increase and the morphological change have not been studied well. This study analyzed the ionospheric density and auroral images and found that significant increases of the energy coincides with evolution of the patch structures in the pulsating aurora. Ground‐based and satellite measurements showed that auroral EEP (>100 keV) coincided with the patch appearance in the late morningMeasurements of the EISCAT radar showed ionization as low as 65 km altitude by ~500 keV electron precipitationEEP activity highly depended on MLT rather than geomagnetic activity