This paper aims to review one of the least used, but no less important, approaches in the assessment of the environmental implications of electricity generation: the Economic Input-Output Life Cycle ...Assessment (EIO-LCA). This methodology is a top-down approach intertwined with the environmental satellite accounts provided by the national statistical office. Through the use of economic input-output (IO) tables and industrial sector-level environmental and energy data, the EIO-LCA analysis allows for broad impact coverage of all sectors directly and indirectly involved with electricity generation. In this study, a brief overview of this methodology and the corresponding assumptions is presented, as well as an updated review of the different applications of the EIO-LCA approach in electricity generation, suggesting a possible classification of the many studies developed in this context. The different ways of overcoming the problem of disaggregation in the electricity sector are also addressed, namely by considering different IO table formats (i.e., symmetric or rectangular tables). This is a particularly relevant feature of our review, as the way in which electricity generation is modeled can result in different calculations of the costs and benefits of environmental policies. In this context, this paper further contributes to the literature by explaining and providing examples of distinct approaches to modeling the electricity sector in IO models on a detailed level.
The prediction of tropospheric ozone concentrations is very important due to the negative impacts of ozone on human health, climate and vegetation. The development of models to predict ozone ...concentrations is thus very useful because it can provide early warnings to the population and also reduce the number of measuring sites. The aim of this study was to predict next day hourly ozone concentrations through a new methodology based on feedforward artificial neural networks using principal components as inputs. The developed model was compared with multiple linear regression, feedforward artificial neural networks based on the original data and also with principal component regression. Results showed that the use of principal components as inputs improved both models prediction by reducing their complexity and eliminating data collinearity.
This study aims to observe the evolution of the electrode–skin interface impedance of surface EMG electrodes over the time taken to determine the time of stabilization. Eight healthy subjects ...participated in the study. Electrode–skin impedance was evaluated in the rectus abdominal muscle every five minutes, over a total period of 50 min. A reduction of 13.23% in the impedance values was observed in minute 10 (p = 0.007), and a reduction of 9.02% was observed in minute 15 (p = 0.029). No statistically significant differences were observed in the other instants evaluated. The findings obtained in the present study demonstrate a decrease in electrode–skin impedance from minute 5 to minute 15, followed by a stabilization period with a low percentage of variation till minute 50.
Principal component analysis (PCA) is a dimensionality reduction method that has identified significant differences in older adults' motion analysis previously not detected by the discrete ...exploration of biomechanical variables. This systematic review aims to synthesize the current evidence regarding PCA use in the study of movement in older adults (kinematics and kinetics), summarizing the tasks and biomechanical variables studied. From the search results, 1685 studies were retrieved, and 19 studies were included for review. Most of the included studies evaluated gait or quiet standing. The main variables considered included spatiotemporal parameters, range of motion, and ground reaction forces. A limited number of studies analyzed other tasks. Further research should focus on the PCA application in tasks other than gait to understand older adults' movement characteristics that have not been identified by discrete analysis.
Poor indoor air quality can adversely affect children's health, comfort and school performance, but existing literature on quantifying indoor air pollutants (IAP) determinants' in nursery and primary ...schools is limited. Following previous studies, this study mainly aimed to quantify determinants of selected IAP, in nursery and primary schools from both urban and rural sites, accounting for seasonal variations. In 101 indoor microenvironments (classrooms, bedrooms and canteens) from 25 nursery and primary schools, CO2, CO, HCOH, NO2, O3, total volatile organic compounds, PM1, PM2.5, PM10, total suspended particles (TSP), and meteorological/comfort parameters were continuously sampled (occupancy and background levels), from at least 24 h to 9 consecutive days (not simultaneously) in each studied room; in some cases weekend was also considered.
Children faced thermal discomfort and inadequate humidity, respectively in 60.1% and 44.1% of the studied classrooms. They were also exposed to high levels of IAP, namely PM2.5 and CO2 respectively in 69.0% and 41.3% of the studied classrooms, mostly in urban sites, depending on season and on occupancy and activity patterns (different amongst age groups). As PM2.5 and CO2 were the major concerning IAP, multivariate linear regression models were built to quantify (explained variability and relative importance) their main determinants, in both occupancy and non-occupancy (background) periods. Models for occupancy periods showed higher explained variability (R2 = 0.64, 0.57 and 0.47, respectively, for CO2, PM2.5 and PM10) than for non-occupancy. Besides background concentrations (43.5% of relative importance), relative humidity (21.1%), flooring material (17.0%), heating (6.7%) and age group of the occupants (5.3%), adjusted for season of sampling (6.4%) were predictors in CO2 occupancy model. In the cases of PM2.5 and PM10 occupancy concentrations, besides background concentrations (71.2% and 67.2% of relative importance, respectively for PM2.5 and PM10), type of school management (8.8% and 15.2%) and flooring material (13.9% and 13.9%), adjusted for season of sampling (6.1% and 3.8%), were the main predictors.
These findings support the need of mitigation measures to reduce IAP levels, and prevention actions to avoid children's exposure. Reducing the time spent indoors in the same microenvironment by doing more and/or longer breaks, improving ventilation and cleaning actions, and avoiding or making a better maintenance hardwood flooring materials, chalkboard use and VOC emitting materials, are practices that should be implemented and their impacts quantified.
•Children are exposed to poor indoor air quality in nursery and primary schools.•PM2.5 and CO2 were the major concerning indoor air pollutants (IAP).•Levels of IAP vary with age group, season and building site location.•Predictors of CO2 during occupancy included humidity, heating and age of occupants.•Flooring material and type of school management are major PM2.5 and PM10 predictors.
The development of microglia
Microglia are the brain's immune cells, and they play important roles in health and neurodegenerative disease. Kracht
et al.
performed single-cell analysis of human ...microglial gene expression and chromatin accessibility and compared the results with those of other studies of human and mice microglial development. By using in situ validation, these data identify fetal microglial subsets that appear to be distinct from adult human microglia, suggesting functional differences between the developing and mature brain.
Science
, this issue p.
530
A molecular blueprint of microglia and their heterogeneity during human fetal development is generated.
Microglia, immune cells of the central nervous system (CNS), are important for tissue development and maintenance and are implicated in CNS disease, but we lack understanding of human fetal microglia development. Single-cell gene expression and bulk chromatin profiles of microglia at 9 to 18 gestational weeks (GWs) of human fetal development were generated. Microglia were heterogeneous at all studied GWs. Microglia start to mature during this developmental period and increasingly resemble adult microglia with CNS-surveilling properties. Chromatin accessibility increases during development with associated transcriptional networks reflective of adult microglia. Thus, during early fetal development, microglia progress toward a more mature, immune-sensing competent phenotype, and this might render the developing human CNS vulnerable to environmental perturbations during early pregnancy.
Assessment of shipping emissions on four ports of Portugal Nunes, R.A.O.; Alvim-Ferraz, M.C.M.; Martins, F.G. ...
Environmental pollution (1987),
December 2017, 2017-Dec, 2017-12-00, 20171201, Letnik:
231, Številka:
Pt 2
Journal Article
Recenzirano
In the last few years, ship emissions have attracted growing attention in the scientific community. The main reason is the constant increase of marine emissions over the last twenty years due to the ...intensification of port traffic. Thus, this study aimed to evaluate ship emissions (PM10, PM2.5, NOx, SO2, CO, CO2, N2O CH4, NMVOC, and HC) through the activity-based methodology in four of the main ports of Portugal (Leixões, Setúbal, Sines and Viana do Castelo) during 2013 and 2014. The analysis was performed according to ship types (bulk carrier, container, general cargo, passenger, Ro-Ro cargo, tanker and others) and operational modes (manoeuvring, hotelling and during cruising). Results indicated that tankers were the largest emitters in two of the four analysed ports. Regarding cruising emissions, container ships were the largest emitters. . CO2, NOx and SO2 estimated emissions represented more than 95% of the cruising and in-port emissions. Results were also compared with the total national emissions reported by the Portuguese Environment Agency, and if the in-port emissions estimated in the present study would have been taken into account to these totals, emissions of NOx and SO2 would increase 15% and 24% in 2013 and 16% and 28% in 2014. Summing up ships seem to be an important source of air pollution, mainly regarding NOx and SO2.
Display omitted
•An activity-based methodology was used to estimate ship emissions in Portugal.•Container ships were the largest emitters.•Largest emissions were observed during cruising.•Ships seems to be an important source of air pollution, mainly regarding NOx and SO2.•An effective political strategy is needed to control atmospheric ship emissions.
If accounted, estimated in-port NOx and SO2 emissions would increase the total national emissions reported in 14% and 19% for 2013, and 15% and 23% for 2014.
In this study, the authors used epigenetics, allelic activity, motif conservation, and other techniques to dissect the regulatory circuitry and mechanistic basis of the association between the
FTO
...region and obesity. An adipocyte thermogenesis pathway that appears important was found.
Obesity affects more than 500 million people worldwide and contributes to type 2 diabetes, cardiovascular disorders, and cancer.
1
Obesity is the result of a positive energy balance, whereby energy intake exceeds expenditure, resulting in the storage of energy, primarily as lipids in white adipocytes. Energy balance is modulated by food consumption and physical activity, as well as by the dissipation of energy as heat through constitutive thermogenesis in mitochondria-rich brown adipocytes in brown fat and through inducible thermogenesis in beige adipocytes in white fat.
2
–
6
Thermogenesis is triggered by mechanisms within the cells themselves or by the sympathetic nervous system . . .
Context.
Proxima Centauri is the closest star to the Sun. This small, low-mass, mid M dwarf is known to host an Earth-mass exoplanet with an orbital period of 11.2 days within the habitable zone, as ...well as a long-period planet candidate with an orbital period of close to 5 yr.
Aims.
We report on the analysis of a large set of observations taken with the ESPRESSO spectrograph at the VLT aimed at a thorough evaluation of the presence of a third low-mass planetary companion, which started emerging during a previous campaign.
Methods.
Radial velocities (RVs) were calculated using both a cross-correlation function (CCF) and a template matching approach. The RV analysis includes a component to model Proxima’s activity using a Gaussian process (GP). We use the CCF’s full width at half maximum to help constrain the GP, and we study other simultaneous observables as activity indicators in order to assess the nature of any potential RV signals.
Results.
We detect a signal at 5.12 ± 0.04 days with a semi-amplitude of 39 ± 7 cm s
−1
. The analysis of subsets of the ESPRESSO data, the activity indicators, and chromatic RVs suggest that this signal is not caused by stellar variability but instead by a planetary companion with a minimum mass of 0.26 ± 0.05
M
⊕
(about twice the mass of Mars) orbiting at 0.029 au from the star. The orbital eccentricity is well constrained and compatible with a circular orbit.
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