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Following approximately 1,800 Finnish children, this longitudinal study examined the associations between students' perceived social support (teacher-student relationships, family support, and peer support), behavioral engagement, cynicism towards school, and academic achievement during the transition from primary to lower secondary school. After controlling for parental educational level and cynicism before the school transition, the results showed that the more students experienced pre-transition peer support, the less they reported post-transition cynicism. Furthermore, pre-transition peer support contributed to students' increased academic achievement and behavioral engagement after the transition through decreased cynicism. The findings indicated that peer support functions as a protective factor against cynicism as students move through the critical school transition phase and positively contributes to students' behavioral engagement and academic achievement.

The promotion of students' engagement with school is an internationally acknowledged challenge in education. There is a need to examine the structure of the concept of student engagement and to discover the best practices for fostering it across societies. That is why the cross-cultural invariance testing of students' engagement measures is highly needed. This study aimed, first, to find the reduced set of theoretically valid items to represent students' affective and cognitive engagement forming the Brief-SEI (brief version of the Student Engagement Instrument; SEI). The second aim was to test the measurement invariance of the Brief-SEI across three countries (Denmark, Finland, and Portugal). A total of 4,437 seventh-grade students completed the SEI questionnaires in the three countries. The analyses revealed that of the total 33 original instrument items, 15 items indicated acceptable psychometric properties of the Brief-SEI. With these 15 items, cross-national factorial validity and invariances across genders and students with different levels of academic performance (samples from Finland and Portugal) were demonstrated. This article discusses the utility of the Brief-SEI in cross-cultural research and its applicability in different national school contexts.

This study examined the reliability and validity of the Classroom Assessment Scoring System-Secondary (CLASS-S) in Finnish classrooms. Trained observers coded classroom interactions based on video recordings of 46 Grade 6 classrooms (450 cycles). Concurrent associations were investigated with respect to teacher self-ratings (e.g., efficacy beliefs and teaching-related stress). Confirmatory factor analysis showed that the hypothesized three-factor structure of the original CLASS-S (Emotional Support, Organizational Support, and Instructional Support), with some modifications, provided a better fit for the data compared with one- and two-factor structures. Structural validity was demonstrated by mostly high factor loadings. Except for two interrater intraclass correlations, all item, scale, and interrater reliabilities were either acceptable or good. The study found some evidence for concurrent associations between the three CLASS-S factors and teacher self-ratings. The results provide evidence of the applicability of the CLASS-S instrument in educational contexts (Finland) outside the United States.

Self-ratings of behavioural engagement, cognitive engagement and school burnout were used in person-centred analyses to identify latent profiles among 2,485 Finnish lower-secondary school students. Three profiles were identified: high-engagement/low-burnout (40.6% of the sample), average-engagement/average-burnout (53.9%), and low-engagement/high-burnout (5.5%). Another sample of lower-secondary school students was used to validate the 3 profiles. The factors most strongly associated with the high-engagement/low-burnout profile of lower-secondary school students' were high levels of support from teachers and family, good academic performance, and lack of truancy. The study indicated that teacher and family support and students' academic achievement are pivotal in understanding student engagement and school burnout.

Methane (CH4/ fluxes were investigated in a subarctic Russian tundra site in a multi-approach study combining plot-scale data, ecosystem-scale eddy covariance (EC) measurements, and a fine-resolution land cover classification scheme for regional upscaling. The flux data as measured by the two independent techniques resulted in a seasonal (May-October 2008) cumulative CH4 emission of 2.4 (EC) and 3.7 gCH4 m-2 (manual chambers) for the source area representative of the footprint of the EC instruments. Upon upscaling for the entire study region of 98.6 km2, the chamber measured flux data yielded a regional flux estimate of 6.7 gCH4 m-2 yr-1. Our upscaling efforts accounted for the large spatial variability in the distribution of the various land cover types (LCTs) predominant at our study site. Wetlands with emissions ranging from 34 to 53 gCH4 m-2 yr-1 were the most dominant CH4-emitting surfaces. Emissions from thermokarst lakes were an order of magnitude lower, while the rest of the landscape (mineral tundra) was a weak sink for atmospheric methane. Vascular plant cover was a key factor in explaining the spatial variability of CH4 emissions among wetland types, as indicated by the positive correlation of emissions with the leaf area index (LAI). As elucidated through a stable isotope analysis, the dominant CH4 release pathway from wetlands to the atmosphere was plantmediated diffusion through aerenchyma, a process that discriminates against 13C-CH4. The CH4 released to the atmosphere was lighter than that in the surface porewater, and δ13C in the emitted CH4 correlated negatively with the vascular plant cover (LAI). The mean value of δ13C obtained here for the emitted CH4, -68.2±2.0 ?, is within the range of values from other wetlands, thus reinforcing the use of inverse modelling tools to better constrain the CH4 budget. Based on the IPCC A1B emission scenario, a temperature increase of 6.1 °C relative to the present day has been predicted for the European Russian tundra by the end of the 21st Century. A regional warming of this magnitude will have profound effects on the permafrost distribution leading to considerable changes in the regional landscape with a potential for an increase in the areal extent of CH4-emitting wet surfaces. [ABSTRACT FROM AUTHOR]

Methane (CH4) fluxes were investigated in a subarctic Russian tundra site in a multiapproach study combining plot scale data, ecosystem scale eddy covariance (EC) measurements and fine resolution land cover classification scheme for regional upscaling. The flux data as measured by the two independent techniques resulted in a seasonal (May-October 2008) cumulative CH4 emission of 2.4 (EC) and 3.7 gCH4 m-2 (manual chambers) for the source area representative of the footprint of the EC instruments. Upon upscaling for the entire study region of 98.6 km2, the chamber measured flux data yielded a regional flux estimate of 6.7 gCH4 m-2 yr-1. Our upscaling efforts accounted for the large spatial variability in the distribution of the various land cover types (LCTs) predominant at our study site. In particular, wetlands with emissions ranging from 34 to 53 gCH4 m-2 yr-1 were the most dominant CH4 emitting surfaces. Emissions from thermokarst lakes were an order of magnitude lower, while the rest of the landscape (mineral tundra) was a weak sink for atmospheric methane. Vascular plant cover was a key factor in explaining the spatial variability of CH4 emissions among wetland types, as indicated by the positive correlation of emissions with the leaf area index (LAI). As elucidated through a stable isotope analysis, the plant transport was the dominant CH4 release pathway that discriminates against heavier δ13C-CH4. The methane released from wetlands was lighter than that in the surface porewater and δ13C in the emitted CH4 correlated with the vascular plant cover (LAI) implying that the plant-mediated CH4 release dominates. A mean value of δ13C obtained here for the emitted CH4, -68.2 ± 2.0 ‰, is within the range of values from other wetlands, thus reinforcing the use of inverse modeling tools to better constrain the CH4 budget. Based on the IPCC A1B emission scenario, a temperature increase of 7°C has been predicted for the tundra region of European Russia by the end of the 21st Century. A regional warming of this magnitude will have profound effects on the permafrost distribution leading to considerable changes in the regional landscape with a potential for an increase in the areal extent of methane emitting wet surfaces. We estimate that a projected increase in air temperature of 7°C with a mere 10% associated increase in the combined areal coverage of willow stands, fens and lakes in the region will lead to a 51% higher amount of CH4 being emitted into the atmosphere by the end of this century. [ABSTRACT FROM AUTHOR]

The Advanced Along-Track Scanning Radiometer (AATSR) on board the ENVISAT satellite is used to study aerosol properties. The retrieval of aerosol properties from satellite data is based on the optimized fit of simulated and measured reflectances at the top of the atmosphere (TOA). The simulations are made using a radiative transfer model with a variety of representative aerosol properties. The retrieval process utilizes a combination of four aerosol components, each of which is defined by their (lognormal) size distribution and a complex refractive index: a weakly and a strongly absorbing fine-mode component, coarse mode sea salt aerosol and coarse mode desert dust aerosol). These components are externally mixed to provide the aerosol model which in turn is used to calculate the aerosol optical depth (AOD). In the AATSR aerosol retrieval algorithm, the mixing of these components is decided by minimizing the error function given by the sum of the differences between measured and calculated path radiances at 3-4 wavelengths, where the path radiances are varied by varying the aerosol component mixing ratios. The continuous variation of the fine-mode components allows for the continuous variation of the fine-mode aerosol absorption. Assuming that the correct aerosol model (i.e. the correct mixing fractions of the four components) is selected during the retrieval process, also other aerosol properties could be computed such as the single scattering albedo (SSA). Implications of this assumption regarding the ratio of the weakly/strongly absorbing fine-mode fraction are investigated in this paper by evaluating the validity of the SSA thus obtained. The SSA is indirectly estimated for aerosol plumes with moderate-to-high AOD resulting from wildfires in Russia in the summer of 2010. Together with the AOD, the SSA provides the aerosol absorbing optical depth (AAOD). The results are compared with AERONET data, i.e. AOD level 2.0 and SSA and AAOD inversion products. The RMSE (root mean square error) is 0.03 for SSA and 0.02 for AAOD lower than 0.05. The SSA is further evaluated by comparison with the SSA retrieved from the Ozone Monitoring Instrument (OMI). The SSA retrieved from both instruments show similar features, with generally lower AATSR-estimated SSA values over areas affected by wildfires. [ABSTRACT FROM AUTHOR]

In this study, a method is presented to retrieve the surface reflectance using the radiances measured at the top of the atmosphere for the two views provided by the Advanced Along-Track Scanning Radiometer (AATSR). In the first step, the aerosol optical depth (AOD) is obtained using the AATSR dual-view algorithm (ADV) by eliminating the effect of the surface on the measured radiances. Hence the AOD is independent of surface properties and can thus be used in the second step to provide the aerosol part of the atmospheric correction which is needed for the surface reflectance retrieval. The method is applied to provide monthly maps of both AOD and surface reflectance at two wavelengths (555 and 659 nm) for the whole year of 2007. The results are validated versus surface reflectance provided by the AERONET-based Surface Reflectance Validation Network (ASRVN). Correlation coefficients are 0.8 and 0.9 for 555 and 659 nm, respectively. The standard deviation is 0.001 for both wavelengths and the absolute error is less than 0.02. Pixel-by-pixel comparison with MODIS (Moderate Resolution Imaging Spectrometer) monthly averaged surface reflectances show a good correlation (0.91 and 0.89 for 555 and 659 nm, respectively) with somewhat higher values (up to 0.05) obtained by ADV over bright surfaces. The difference between the ADV- and MODIS-retrieved surface reflectances is smaller than ±0.025 for 68.3% of the collocated pixels at 555 nm and 79.9% of the collocated pixels at 659 nm. An application of the results over Australia illustrates the variation in the surface reflectances for different land cover types. The validation and comparison results suggest that the algorithm can be successfully used for both the AATSR and ATSR-2 (which has characteristics similar to AATSR) missions, which together cover a 17-year period of measurements (1995–2012), as well as a prototype for the Sea and Land Surface Temperature Radiometer (SLSTR) planned to be launched in the fall of 2015 onboard the Sentinel-3 satellite. [ABSTRACT FROM AUTHOR]

The retrieval of aerosol properties from satellite data is based on the optimized fit of simulated and measured radiances at the top of the atmosphere (TOA). The simulations are made using a radiative transfer model with a variety of representative aerosol properties. The optimum fit is obtained for a certain combination of aerosol components, which are externally mixed to provide the aerosol model which in turn is used to calculate the aerosol optical depth (AOD). However, other aerosol properties could be provided. In the aerosol retrieval algorithm (ADV) applied to data from the Advanced Along Track Scanning Radiometer (AATSR), four aerosol components are used, each of which is defined by their (lognormal) size distribution and a complex refractive index. The fine mode fraction is a continuous mixture of weakly and strongly absorbing components which allows for the definition of any absorbing aerosol model within the specified limits. Hence, assuming that the correct aerosol model is selected during the retrieval process, also the single scattering albedo (SSA) should correctly be retrieved. In this paper we present the SSA retrieval using the ADV algorithm by application to wildfires over Russia in the summer of 2010. Together with the AOD, the SSA provides the aerosol absorbing optical depth (AAOD). The results are compared with AERONET data, i.e. AOD level 2.0 and SSA and AAOD inversion products. The RMSE is 0.03 for SSA and 0.02 for AAOD. The SSA is further evaluated by comparison with the SSA retrieved from the Ozone Monitoring Instrument (OMI). The SSA retrieved from both instruments show similar features, but the AATSR-retrieved SSA values over areas affected by wildfires are lower. [ABSTRACT FROM AUTHOR]

In this study, a method is presented to retrieve the surface reflectance using reflectance measured at the top of the atmosphere for the two views provided by the Along-Track Scanning Radiometer (AATSR). In the first step, the aerosol optical depth (AOD) is obtained using the AATSR dual view algorithm (ADV) by eliminating the effect of the surface on the measured radiances. Hence the AOD is independent of surface properties and can thus be used in the second step to provide the aerosol part of the atmospheric correction which is needed for the surface reflectance retrieval. The method is applied to provide monthly maps of both AOD and surface reflectance at two wavelengths (555 and 659 nm) for the whole year of 2007. The results are validated vs. surface reflectance provided by the AERONET-based Surface Reflectance Validation Network (ASRVN). Correlation coefficients are 0.8 and 0.9 for 555 and 659 nm, respectively. The standard deviation is 0.001 for both wavelengths and the absolute error is less than 0.02. Pixel-by-pixel comparison with MODIS (MODerate resolution Imaging Spectrometer) monthly averaged surface reflectances show a good correlation (0.91 and 0.89 for 555 and 659 nm, respectively) with some (up to 0.05) overestimation by ADV over bright surfaces. The difference between the ADV and MODIS retrieved surface reflectance is smaller than ±0.025 for 68.3% of the collocated pixels at 555nm and 79.9% of the collocated pixels at 659 nm. An application of the results over Australia illustrates the variation of the surface reflectances for different land cover types. The validation and comparison results suggest that the algorithm can be successfully used for the both AATSR and ATSR-2 (which has characteristics similar to AATSR) missions, which together cover 17 years period of measurements (1995-2012), as well as a prototype for The Sea and Land Surface Temperature Radiometer (SLSTR) to be launched in 2015 onboard the Sentinel-3 satellite. [ABSTRACT FROM AUTHOR]

The uncertainty associated with satellite-retrieved aerosol properties is needed when these data are used to constrain chemical transport or climate models by using data assimilation. Global uncertainty as provided by comparison with independent ground-based observations is usually not adequate for that purpose. Rather the per-pixel uncertainty is needed. In this work we describe how these are determined in the AATSR dual and single view aerosol retrieval algorithms (ADV and ASV) which are used to retrieve aerosol optical properties from reflectance measured at the top of the atmosphere. AATSR is the Aerosol Along-Track Scanning Radiometer which flies on the European Space Agency Environmental Satellite ENVISAT. In addition, issues related to multi-year retrievals are described and discussed. The aerosol optical depth (AOD) retrieved for the year 2008 is validated versus ground-based AERONET sun photometer measurements with good agreement (r = 0.85). The comparison of the AOD uncertainties with those provided by AERONET shows that they behave well in a statistical sense. Other considerations regarding global multi-year aerosol retrievals are presented and discussed [ABSTRACT FROM AUTHOR]

We report here the carbon dioxide (CO2) budget of a 98.6 km² subarctic tundra area in northeast European Russia based on measurements at two different scales and two independent upscaling approaches. Plot-scale measurements (chambers on terrestrial surfaces, gas gradient method and bubble collectors on lakes) were carried out from July 2007 to October 2008. The landscape-scale eddy covariance (EC) measurements covered the snow-free period of 2008. The annual net ecosystem exchange (NEE) of different land cover types ranged from -251 to 84 g Cm-2. Leaf area index (LAI) was an excellent predictor of the spatial variability in gross photosynthesis (GP), NEE and ecosystem respiration (ER). The plot-scale CO2 fluxes were first scaled up to the EC source area and then to the whole study area using two data sets: a land cover classification and a LAI map, both based on field data and a 2.4m pixel-sized Quick- Bird satellite image. The good agreement of the CO2 balances for the EC footprint based on the different measuring techniques (-105 to -81 g Cm-2 vs. -79 g Cm-2; growing season 2008) justified the integration of the plot-scale measurements over the larger area. The regional CO2 balance based on area-integrated plot-scale measurements was -41 or -79 g Cm-2 yr-1 according to the two upscaling methods, the land cover classification and the LAI map, respectively. Due to the heterogeneity of tundra, the effect of climate change on CO2 uptake will vary strongly according to the land cover type and, moreover, likely changes in their relative coverage in the future will have great impact on the regional CO2 balance. [ABSTRACT FROM AUTHOR]

We report here the carbon dioxide (CO2) budget of a 98.6-km² subarctic tundra area in Northeast European Russia based on measurements at two different scales and two independent up-scaling approaches. Plot scale measurements (chambers on terrestrial surfaces, gas gradient method and bubble collectors on lakes) were carried out from July 2007 to October 2008. The landscape scale eddy covariance (EC) measurements covered the snow-free period 2008. The annual net ecosystem exchange (NEE) of different land cover types ranged from -251 to 84 gCm-2. Leaf area index (LAI) was an excellent predictor of the spatial variability in gross photosynthesis (GP), NEE and ecosystem respiration (ER). The plot scale CO2 fluxes were first scaled up to the EC source area and then to the whole study area using two data sets: a land cover classification and a LAI map, both based on field data and 2.4m pixel-sized Quickbird satellite image. The good agreement of the CO2 balances for the EC footprint based on the different methods (-105 to -81 gCm-2 vs. -79 gCm-2; growing season 2008) justified the integration of the plot scale measurements over the larger area. The annual CO2 balance for the study region was -67 to -41 gCm-2. Due to the heterogeneity of tundra, the effect of climate change on CO2 uptake will vary strongly according to the land cover type and, moreover, likely changes in their relative coverage in future will have great impact on the regional CO2 balance. [ABSTRACT FROM AUTHOR]

This paper presents theoretical and experimental results about constrained non-negative matrix factorization (NMF) to model the excitation of the musical instruments. These excitations represent vibrating objects, while the filter represents the resonance structure of the instrument, which colors the produced sound. We propose to model the excitations as the weighted sum of harmonically constrained basis functions, whose parameters are tied across different pitches of an instrument. An NMF-based framework is used to learn the model parameters. We assume that the excitations of a well-tempered instrument should possess an identifiable characteristic structure whereas the conditions of the music scene might produce variations in the filter. In order to test the reliability of our proposal, we evaluate our method for a music transcription task in two scenarios. On the first one, comparison with state-of-the-art methods has been performed over a dataset of piano recordings obtaining more accurate results than other NMF-based algorithms. On the second one, two woodwind instrument databases have been used to demonstrate the benefits of our model in comparison with previous excitation-filter model approaches. [ABSTRACT FROM PUBLISHER]

We use Fermi liquid theory to study the mechanical impedance of ³He-4He mixtures at low temperatures. The theory is applied to the case of vibrating wires, immersed in the liquid. We present numerical results based on a direct solution of the Landau-Boltzmann equation for the ³He quasiparticle distribution for the full scale of the quasiparticle mean-free path £. The two-fluid nature of mixtures is taken into account in the theory, and the effect of Fermi liquid interactions and boundary conditions are studied in detail. The results are in fair quantitative agreement with experimental data. In particular, we can reproduce the anomalous decrease in inertia, observed in vibrating wire experiments reaching the ballistic limit. The essential effect of the experimental container and second-sound resonances is demonstrated. [ABSTRACT FROM AUTHOR]

Discusses the influence of geology, discharge regime, vegetation type, vegetation density, slope, and permafrost conditions on periglacial channel morphology in the Usa catchment of northern European Russia. Idea that dense vegetation is an important factor in determining the meandering morphology because it inhibits the sediment supply and braided conditions of rivers; View that differences in vegetation types, taiga in the south, tundra in the north, have no effect on channel plan form.

Acute effects on the upper and lower respiratory tract due to inhalation exposure to Stachybotrys chartarum (Sc) extract were investigated in mice. In addition, the capacity of the Sc exposure to activate immune system and cause inflammation in the respiratory tract was studied. The inhalation of Sc extract aerosols was observed to provoke sensory irritation in the airways of both naive and Sc-immunized mice. In contrast, exposure to aerosolized ovalbumin or phosphate buffered saline did not cause this effect. Exposure to Sc twice a week for 3 wk increased significantly the serum total immunoglobulin E (IgE) levels in BALB/c mice immunized with Sc as well as in nonimmunized mice. A slight presence of inflammatory cells was observed in the alveoli 3 days after the last exposure to Sc. In conclusion, Sc extract has the capacity to provoke sensory irritation in the murine airways and to activate the murine immune system. [ABSTRACT FROM AUTHOR]

Acute effects of repeated inhalation exposure to Stachybotrys chartarum extract (Sc) on the respiratory tract were investigated in Sc-immunized (group Sc/Sc) and non-immunized (PBS/Sc) mice. Control animals were exposed to aerosolized water (PBS/water) and one group was immunized against Sc but not exposed via the airways (Sc/-). Immune responses, measured as the production of total IgE and Sc-specific IgA, IgG1 and IgG2a antibodies, the cytokines IL-4, IL-10 and IFN-γ by spleen cells, spleen cell proliferation and signs of inflammation in the respiratory tract were studied. Inhalation of Sc aerosols (but not water) induced sensory irritation in both the Sc-immunized and non-immunized mice on every exposure. Spleen cells from Sc/Sc mice exhibited higher proliferation indices and production of IL-10 and IL-4 compared with the responses in the other groups. Sc immunization increased serum antibody levels except for IgA. Inhalation of Sc increased IgG2a in Sc-immunized mice and decreased IgE levels in the non-immunized mice. Clear signs of inflammation were not detected in tissue samples of the upper respiratory tract in the exposed groups, whereas mild focal lung inflammation was observed in the Sc/Sc mice and one PBS/Sc mouse. As a conclusion, inhalation of Sc aerosols caused sensory irritation in the murine airways. Cytokine production and Sc-specific proliferative responses were activated in spleen cells of Sc-immunized mice, whereas only the level of IgG2a antibody was increased. [ABSTRACT FROM AUTHOR]

We tested experimentally whether shoot feeding aphids Cinara pinea (Mordv.) can promote the development of Gremmeniella abietina (Lagerb.) Morelet, a fungus which causes Scleroderris canker disease in conifers. Pine seedlings were infested with aphids at two different times, and subsequently inoculated with conidia of G. abietina at two different times. The degree of infestation was classified into three groups based on the number of aphids/seedling: none, one (low level), and three (high level). Because of parthenogenetic reproduction, the number of aphids increased during the summer, so we also used aphid numbers to explain the development of the symptoms. Necrosis caused by G. abietina was more prevalent in seedlings infested by aphids in June, and inoculated with fungus in July. Expressed as percents of the total length of the shoots, the necrosis had advanced 50%, 70%, and 95% with no, low, and high aphid levels, respectively. Canker formation was significantly greater when G. abietina conidia were inoculated in July, compared to August. In August, there were no statistically significant differences in the intensity of disease between aphid infestation levels, but the mean number of aphids was related to disease intensity. In the spring following infection, seedlings with aphids had more dead and fewer healthy terminal buds compared to seedlings without aphids. [ABSTRACT FROM AUTHOR]