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This study aimed to explore the variability in nasal airflow patterns among different sexes and populations using computational fluid dynamics (CFD). We focused on evaluating the universality and applicability of dimensionless parameters R (bilateral nasal resistance) and ϕ (nasal flow asymmetry), initially established in a Caucasian Spanish cohort, across a broader spectrum of human populations to assess normal breathing function in healthy airways. In this retrospective study, CT scans from Cambodia (20 males, 20 females), Russia (20 males, 18 females), and Spain (19 males, 19 females) were analyzed. A standardized CFD workflow was implemented to calculate R‐ϕ parameters from these scans. Statistical analyses were conducted to assess and compare these parameters across different sexes and populations, emphasizing their distribution and variances. Our results indicated no significant sex‐based differences in the R parameter across the populations. However, moderate sexual dimorphism in the ϕ parameter was observed in the Cambodian group. Notably, no geographical differences were found in either R or ϕ parameters, suggesting consistent nasal airflow characteristics across the diverse human groups studied. The study also emphasized the importance of using dimensionless variables to effectively analyze the relationships between form and function in nasal airflow. The observed consistency of R‐ϕ parameters across various populations highlights their potential as reliable indicators in both medical practice and further CFD research, particularly in diverse human populations. Our findings suggest the potential applicability of dimensionless CFD parameters in analyzing nasal airflow, highlighting their utility across diverse demographic and geographic contexts. This research advances our understanding of nasal airflow dynamics and underscores the need for additional studies to validate these parameters in broader population cohorts. The approach of employing dimensionless parameters paves the way for future research that eliminates confounding size effects, enabling more accurate comparisons across different populations and sexes. The implications of this study are significant for the advancement of personalized medicine and the development of diagnostic tools that accommodate individual variations in nasal airflow. [ABSTRACT FROM AUTHOR]

In hospitals, operating rooms are energy-intensive spaces, due to the high flow of outside air required to achieve the necessary indoor air quality. Operating rooms demand ventilation continuously, despite periods of low daily surgical activity. However, by controlling ventilation during inactive periods in the operating room, significant energy savings can be achieved, avoiding penalties on IAQ levels. This paper evaluates the energy savings achieved by introducing ventilation flow control and regulation systems in operating rooms of hospitals located in different climatic zones within Spain. In addition, emissions and economic savings have also been evaluated. Two control and regulation strategies of the air flow to be supplied and extracted in the operating rooms, during periods of inactivity, are studied and include regulation by schedule and regulation by occupancy. Data from a 900-bed university hospital center are used as a reference to evaluate the average occupancy of the operating rooms, and the energy consumption, thus validating the model for calculating the demand of a typical operating room. The energy savings for the regulation by occupancy are 37.5%, and the regulation by schedule are 40% of the annual demand, with respect to an operating room working permanently. [ABSTRACT FROM AUTHOR]

The wine industry produces large quantities of wastewater that often contains high levels of organic matter and nutrients, like nitrogen and phosphorous. In particular, nitrogen pollution can be harmful, even at low levels, since infants are vulnerable to nitrates in drinking water, and excess nitrogen can harm the health of soils and waterways. Herein, an innovative compact, modular, and mobile treatment wetland (TW) using cork by product as the only granular media was used to treat the final effluents from the Codorniu winery (Sant Sadurní d'Anoia, Spain). The TW was operated during two 5-month periods with or without intermittent induced aeration (40 min cycles, 90 L/min air flow rate). Nitrate (N-NO 3) and total nitrogen (TN) removal were higher (52.8% and 46.8%, respectively, p < 0.05) during TW operation under aerated-condition. Additionally, q PCR analysis of 16S rRNA, nir S and nos Z genes revealed that intermittent induced aeration facilitates N-NO 3 reduction by the stimulation of denitrifying bacteria in the TW biofilm (11.4% increase in nir S copies number/g cork sample, p < 0.05) as well as increasing the number of heterotrophic bacteria adhered to cork (25.5% increase in 16S rRNA copies number/g cork sample, p < 0.05). Moreover, SEM images demonstrated the suitability of cork as a resistant filter media for TW after long-term system operation (1.5 years). In conclusion, our results suggest that aeration improved nitrogen compounds removal compared to the non-aerated period, without affecting phosphorous elimination. Additionally, residual cork is presented here in a circular bioeconomy view, as a suitable filling media to treat winery wastewater that can provide additional carbon source to increase C/N rate stimulating denitrification, as well as a reliable organic substrate for biomass growth. [Display omitted] • Cork filled TW could be an appropriate technology to treat and/or remediate winery wastewater with high nitrate content. • The induced aeration in a vertical TW using cork as filter medium showed higher removal rates for NO 3 -N and TN. • The saturated-aerated vertical TW increased microbial abundance with the presence of the denitrification genes nir S and nos Z. • The nir S genes showed higher relative abundance than nos Z. [ABSTRACT FROM AUTHOR]

Thermal desorption, by a rotary kiln of mercury contaminated soil and mine wastes, has been used in order to volatilize mercury from the contaminated medium. Solar thermal desorption is an innovative treatment that uses solar energy to increase the volatility of contaminants, which are removed from a solid matrix by a controlled air flow system. Samples of soils and mine wastes used in the experiments were collected in the abandoned Valle del Azogue mine (SE, Spain), where a complex ore, composed mainly of cinnabar, arsenic minerals (realgar and orpiment) and stibnite, was mined. The results showed that thermal treatment at temperatures >400 °C successfully lowered the Hg content (2070--116 ppm) to <15 mg kg-1. The lowest values of mercury in treated samples were obtained at a higher temperature and exposition time. The samples that showed a high removal efficiency (>99%) were associated with the presence of significant contents of cinnabar and an equivalent diameter above 0.8 mm. [ABSTRACT FROM AUTHOR]

In recent years, there has been growing concern regarding energy efficiency in the building sector with energy requirements increasing worldwide and now responsible for about 40% of final energy consumption in Europe. Previous research has shown that ventilated façades help to reduce energy use when cooling buildings in hot and temperate climates. Of the different ventilated façade configurations reported in the literature, the configuration of ventilated façade with window rarely has been studied, and its 3D thermodynamic behavior is deserving of further analysis and modeling. This paper examines the thermal behavior of an opaque ventilated façade with a window, in experimentally and numerical terms and its impact in energy savings to get indoor comfort. Field measurements were conducted during the winter, spring and summer seasons of 2021 using outdoor full scale test cells located in Seville (southern Spain). The modeling of the ventilated façade was carried out using a three-dimensional approach taking into account the 3D behavior of the air flow in the air cavity due to the presence of the window. The validation and comparison process using experimental data showed that the proposed model provided good results from quantitative and qualitative point of view. The reduction of the heat flux was assessed by comparing the energy performance of a ventilated façade with that of an unventilated façade. Both experimental and numerical results showed that the ventilated façade provided a reduction in annual total energy consumption when compared to the unventilated façade, being compensated the winter energy penalization by the summer energy savings. This reduction is about 21 % for the whole typical climatic year showing the ability of the opaque ventilated façade studied to reduce energy consumption to insure indoor comfort, making its suitable for use in retrofitting the energy-obsolete building stock built in Spain in the middle decades of the 20 century. [ABSTRACT FROM AUTHOR]

Abstract: The Pyrenees Mountains, the natural border between France and Spain, have experienced a large increase in road traffic in the last decade. Due to this fact, a research program named PAP (Pollution Atmospheric in the Pyrenees) was established in 2004 by several laboratories from Spain and France to address the influence of meteorological regimes on the pollution levels of two adjacent valleys, Aspe valley (France) and Canfranc valley (Spain), situated in the center of the Pyrenean range. Pollution measurements show that mean ozone concentrations increase with height. In Sarrance, the site placed at the bottom of the valleys at 335 m above sea level (ASL), the mean ozone value was 23 ppb, whereas at the Pic Midi observatory (2877 m ASL), the top of the PAP network, the value found for mean ozone values was 52 ppb. A linear trend fits this altitudinal variation with a vertical gradient of 17 ppb km−1. The data demonstrate that the observatories located over 1400 m ASL do not show the classical mean daily ozone cycle, and that mean ozone concentrations throughout the day are nearly constant. By contrast, below 1400 m ASL, the classical mean daily ozone cycle is clear, reaching a maximum around noon. These findings indicate that the photochemical reactions are almost inactive at the elevated observatories and, as a result, it can be concluded that ozone levels at those locations are mostly caused by advection of aged air masses. Consequently, we could find that the gradient inside the valleys follows a linear trend of 29 ppb km−1. Finally, it has been observed that in north Foehn situations, intrusions of polluted air coming from the Free Troposphere (FT) can be detected in the upper part of the Spanish valley of Canfranc, where the mean daily ozone cycle changes significantly and becomes similar to the ones measured at the stations situated above 1400 m ASL. However, the results also pointed out that, except for the Foehn situations, the different local air flow regimes do not strongly affect the mean diurnal cycle of ozone and the mean ozone concentrations. [Copyright &y& Elsevier]

Abstract: A combined approach using two surface geophysical methods (capacity-coupled geoelectrics and ground-penetrating radar) and careful inspection by optical televiewer probes in a network of boreholes (<30m) has been undertaken at an experimental karst site located in the immediate vicinity of the Nerja cave (S. Spain), an important show cave developed in Triassic dolomitic marbles. Our approach has proved helpful in characterizing geometrically and speleologically the vadose zone of these highly heterogeneous environments in that we have been able to identify a considerable number of caves and arrive at an idea of their approximate volume and length. Televiewer logging in the borehole network allowed us to identify a number of karst features: horizontal and vertical openings and cavities, as well as the relative degree of speleothem development. We had previously made a systematic record of the CO2 content of the air inside these boreholes and the results of this earlier study together with the present one have allowed us to further our knowledge of the ventilation patterns in the vadose zone of the research site, which suggest that high CO2 contents (up to 60,000ppm) are directly linked to the degree of karstification. The general geometrical model of karstification in the area suggests a common genesis for the Nerja cave and the numerous cavities revealed during this study. The flows of CO2-rich air and the ventilation patterns in the vadose zone in general seem to be different in the Nerja cave from those in the network of small cavities surrounding it, a circumstance that most likely derives from the fact that the main cave communicates both naturally and artificially with the outside atmosphere. The air-flow regime in the network of boreholes has still to be studied in detail however. [Copyright &y& Elsevier]

The structure and evolution of the sea breeze in the north-west part of the Mediterranean (Catalonia, north-east Spain) is studied both experimentally and, predominantly, using numerical models to increase understanding of sea-breeze structure and three-dimensional (3D) pollution distributions in coastal environments. Sea-breeze components are modelled and analyzed using the fifth-generation Pennsylvania State University-National Centre for Atmospheric Research Mesoscale Model (MM5). The results show that the growth and structure of the sea-breeze circulation is modulated by the synoptic flow and especially by the complex topography of the area. 3D pollution transport in a sea breeze is modelled by coupling the MM5 to the Community Multiscale Air Quality (CMAQ) model, with results indicating that topography and synoptic flow are the main factors modulating horizontal and vertical pollutant transport in sea-breeze episodes. In this way, horizontal dispersion is limited by the complex topography of the area, whilst the sea-breeze flow is intensified by anabatic upslope winds that contribute to vertical pollutant transport. The numerical model results also indicate that the sea-breeze circulation with a weak return flow at upper levels grows due to a synoptic onshore wind component. However, such a sea-breeze circulation is capable of transporting pollutants towards the coast. [ABSTRACT FROM AUTHOR]

Abstract: In the present work the gasification process of cork residues sourced in an industrial procedure in the regions of Extremadura (Spain) and Alentejo (Portugal) was studied. These by-products were classified as black agglomerates (low and high granulate), sandpaper dust (white agglomerate) and triturated wood. Samples of several residues obtained through different phases of the cork manufacturing process were collected and next quantified. In order to test their ability to produce energy, all the referred residues were gasified. The air flow was varied, ranging from 50 up to 400cm3 min−1. The thermal treatment temperature was also varied from 650°C up to 800°C. The experimental results indicate that the optimal conditions in terms of energy production were an air flow equal to 200cm3 min−1 and a treatment temperature of 800°C. [Copyright &y& Elsevier]

Abstract: An empirical algorithm has been developed to compute the sea surface CO2 fugacity (fCO2 sw) in the Bay of Biscay from remotely sensed sea surface temperature (SSTRS) and chlorophyll a (chl a RS) retrieved from AVHRR and SeaWiFS sensors, respectively. Underway fCO2 sw measurements recorded during 2003 were correlated with SSTRS and chl a RS data yielding a regression error of 0.1±7.5 µatm (mean±standard deviation). The spatial and temporal variability of air–sea fCO2 gradient (ΔfCO2) and air–sea CO2 flux (FCO2) was analyzed using remotely sensed images from September 1997 to December 2004. An average FCO2 of −1.9±0.1 mol m−2 yr−1 characterized the Bay of Biscay as a CO2 sink that is suffering a significant long-term decrease of 0.08±0.05 mol m−2 yr−2 in its capacity to store atmospheric CO2. The main parameter controlling the long-term variability of the CO2 uptake from the atmosphere was the air–sea CO2 transfer velocity (57%), followed by the SSTRS (10%) and the chl a RS (2%). [Copyright &y& Elsevier]

Abstract: Indoor radon concentration has been measured in workplaces and dwellings of the volcanic region of La Garrotxa and in the vicinity of the recently active Amer fault, in northeastern Spain. The radon levels obtained do not constitute a relevant risk for workers. Higher indoor radon levels have been found on volcanic materials (mean 133Bqm−3, range 15–1464Bqm−3) than on non-volcanic materials (mean 67Bqm−3, range 16–327Bqm−3). A summertime elevation of radon levels that does not happen in buildings placed on non-volcanic materials has been observed as consequence of convective airflow from the soil to indoor environments through a network of subterranean channels present in volcanic materials. This effect is very important if the subterranean channel reaches the indoor environment through natural holes called blowholes. A possible influence of the Amer fault has been seen in La Vall d''en Bas, one of the five villages studied, which has a more homogeneous underlying geology. [Copyright &y& Elsevier]

• Regulatory measures are not adequate to guarantee healthy environment indoors. • In Italy air flows required in the applicable regulations are more restrictive than in Spain. • The number of renewals per hour is low, both for Italy and Spain. • The need arises to update ventilation legislation with adequate criteria to avoid aerosol contagion indoors. With the arrival of the SARS-CoV-2 coronavirus, the scientific academia, as well as policymakers, are striving to conceive solutions as an attempt to contain the spreading of contagion. Among the adopted measures, severe lockdown restrictions were issued to avoid the diffusion of the virus in an uncontrolled way through public spaces. It can be deduced from recent literature that the primary route of transmission is via aerosols, produced mainly in poorly ventilated interior areas where infected people spend a lot of time with other people. Concerning contagion rates, accumulated incidence or number of hospitalizations due to COVID-19, Spain, and Italy have reached very high levels. In this framework, a regression analysis to assess the feasibility of the indoor ventilation measures established in Spain and Italy, with respect to the European framework, is here presented. To this aim, ten cases of housing typology were and analyzed. The results show that the measures established in the applicable regulations to prevent and control the risk of contagion by aerosols are not adequate to guarantee a healthy environment indoors. The current Italian guidelines are more restrictive than in Spain, yet the ventilation levels are still insufficient in times of pandemic. [ABSTRACT FROM AUTHOR]

Historically, the olive grove has been one of the most emblematic ecosystems in Mediterranean countries. Currently, in Andalusia, Spain, the land under olive grove cultivation exceeds 1.5 million hectares, approximately 17% of the regional surface. Its exploitation has traditionally been based on the use of the available land and heterogeneous plantations, with different species adapted to southern Mediterranean climatic conditions, and to the management of the traditional olive cultivation culture. The objective of this work is to characterize the mechanical behavior of the atmospheric surface boundary layer (SBL) (under neutral stability) interacting with different olive grove configurations. Experimental tests were carried out in the Boundary Layer Wind Tunnel (BLWT) of the Andalusian Institute for Earth System Research (IISTA), University of Granada. Three representative configurations of olive groves under neutral atmospheric conditions were tested. The wind flow time series were recorded at several distances and heights downwind the olive plantation models with a cross hot wire anemometry system. Herein, this paper shows the airflow streamwise, including the mean flow and the turbulent characteristics. The spatial variability of these two mechanical magnitudes depends on, among others, the size, the agro-forest length, the layout of the tree rows, the porosity, the tree height, the crown shape and the surface vegetation cover. The aerodynamic diameter and Reynolds number for each agro-forest management unit are proposed as representative variables of the system response, as these could be related to olive grove management. The plantation, in turn, conforms to a windbreak, which affects the microclimate and benefits the elements of the ecosystem. Detailed knowledge of these variables and the interaction between the ecosystem and the atmosphere is relevant to optimize the resources management, land use and sustainability of the overall crop. Thus, this paper presents preliminary work to relate atmospheric variables to environmental variables, some of which could be humidity, erosion, evapotranspiration or pollen dispersion. [ABSTRACT FROM AUTHOR]

This work presents the analysis of weekly 7Be activity concentrations in the air measured in Bilbao (northern Spain) by collecting aerosols in filters over a ten years period (2009–2018). 7Be level is in the 0.35–7.3 mBq/m3 range, with a mean of 3.20 ± 1.12 mBq/m3. The trend, cycle, seasonal and monthly variability are evaluated using time series analysis techniques. The results indicate the impact of sunspots (24th solar cycle) on interannual 7Be activity concentrations, and a significant seasonal and monthly variation, with maximum concentrations occurring in spring-summer and minimum in the winter. The correlation of different 7Be ranges with local meteorological parameters, such as precipitation, temperature, relative humidity, and pressure, is also addressed, with precipitation having the greatest impact on 7Be activity values. The analysis of synoptic airflows, by calculating the back-trajectory clusters, and local winds at surface level reveals the important influence of the arrival of slow northwest Atlantic flows and the development of breezes on reaching high 7Be activity concentrations in this area. [ABSTRACT FROM AUTHOR]

• Small test setups for both pure and hybrid solar chimney system are built. • A numerical simulation method for the hybrid system is proposed and validated. • Hybrid systems greatly increase the total power output. • Hybrid systems can reduce land requirement of the solar-assisted air cleaning system. Under the background of global energy shortage and environment deterioration, researchers of the world pay high attention to develop renewable energy. This paper proposes a hybrid solar chimney and photovoltaic system for the novel solar-assisted air cleaning system. Small-scale laboratory setups are designed and fabricated. Experimental results reveal that replacing 50.60% acrylic glass of the collector top with photovoltaic panels will reduce the thermal air flow rate only by 14%, but generate significant electric power output. A three-dimensional numerical simulation model is established and validated by experimental results (air flow rate, temperature distribution). The model includes solar ray tracing model, surface to surface radiation model, buoyancy-driven flow and heat transfer model and power generation model. Then, this model is used to predict a large-scale system based on the Manzanares pilot power plant in Spain. For the large-scale system, the electrical energy generated by the photovoltaic panels can be used to drive suction fans to increase air input. Covering the entire top surface of the collector by photovoltaic panels (113-meter-wide), the total air flow rate would increase to 2.21 times compared with the system without photovoltaic panels. And setting photovoltaic panels on the collector bottom with 113-meter-wide, the total air flow rate would increase to 2.42 times. Thus, adding photovoltaic panels for the collector can greatly improve the utilization of solar energy. It can increase the amount of air purification, or reduce land requirement for the same flow rate. [ABSTRACT FROM AUTHOR]

The exposed surface of the eye is richly innervated by sensory nerve fibers originated at trigeminal ganglion neurons. They reach the cornea and bulbar conjunctiva as thin myelinated or unmyelinated nerve fibers lacking of morphological terminal specialization. However, electrophysiological studies have shown that sensory neurons innervating the eye are functionally heterogeneous. Based upon their response to specific stimuli, different functional types of sensory nerve fibers have been identified in the cornea and bulbar conjunctiva. Mechanonociceptor fibers (~20% of the total) react only to mechanical forces; polymodal nociceptor fibers (~70%) respond to mechanical forces but also to heat, exogenous chemical irritants and endogenous inflammatory mediators. Cold‐sensitive fibers (~10‐15%) display an ongoing impulse activity at basal corneal temperatures and increase markedly their firing frequency with moderate cooling. Differences in transduction capacity among ocular sensory fibers are attributable to the variable expression of different types of transduction channels (members of the TRP superfamily, ASICs, 2P domain K channels..) HCN channels and of voltage‐dependent Na+ K+ and Ca2+ channels. Under pathological conditions (inflammation, surgical injury, dryness of the ocular surface) activity of ocular sensory nerve fibers changes markedly as the result of short‐term changes in ion channel expression secondary to local release of inflammatory agents and growth factors, and of long‐lasting modifications in gene expression. This leads to the development of spontaneous activity and of abnormal responsiveness to natural stimuli. Each of the functional types of corneal sensory fibers can be stimulated selectively in humans, using an instrument (the Belmonte esthesiometer) that delivers gas pulses of variable flow at neutral temperature (mechanical stimuli), CO2 concentrations (acidic stimuli) and cooled or warmed air at subthreshold flow levels (cold and heat stimuli) onto the ocular surface. Stimulation of the different functional populations of nerve fibers of the ocular surface evokes a specific quality of sensation that includes a variable component of unpleasantness. The relationship between activation of the different classes of ocular surface sensory fibers under normal and pathological conditions and the quality of the experienced sensation is now being elucidated. In addition to their role in the production of conscious innocuous and noxious sensations referred to the eye surface, sensory fibers appear to play a role in the maintenance of the ocular surface homeostasis, including basal and reflex modulation of tearing and trophic maintenance of corneal and conjunctival tissues. Supported by grants BFU2005‐08741 and CONSOLIDER‐INGENIO 2010 CSD2007‐00023 from the Government of Spain. [ABSTRACT FROM AUTHOR]