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Sea salt aerosols play an important role in the radiation budget and atmospheric composition over the Arctic, where the climate is rapidly changing. Previous observational studies have shown that Arctic sea ice leads are an important source of sea salt aerosols, and modeling efforts have also proposed blowing snow sublimation as a source. In this study, size-resolved atmospheric particle number concentrations and chemical composition were measured at the Arctic coastal tundra site of Utqiaġvik, Alaska, during spring (3 April–7 May 2016). Blowing snow conditions were observed during 25 % of the 5-week study period and were overpredicted by a commonly used blowing snow parameterization based solely on wind speed and temperature. Throughout the study, open leads were present locally. During periods when blowing snow was observed, significant increases in the number concentrations of 0.01–0.06 µm particles (factor of 6, on average) and 0.06–0.3 µm particles (67 %, on average) and a significant decrease (82 %, on average) in 1–4 µm particles were observed compared to low wind speed periods. These size distribution changes were likely caused by the generation of ultrafine particles from leads and/or blowing snow, with scavenging of supermicron particles by blowing snow. At elevated wind speeds, both submicron and supermicron sodium and chloride mass concentrations were enhanced, consistent with wind-dependent local sea salt aerosol production. At moderate wind speeds below the threshold for blowing snow as well as during observed blowing snow, individual sea spray aerosol particles were measured. These individual salt particles were enriched in calcium relative to sodium in seawater due to the binding of this divalent cation with organic matter in the sea surface microlayer and subsequent enrichment during seawater bubble bursting. The chemical composition of the surface snowpack also showed contributions from sea spray aerosol deposition. Overall, these results show the contribution of sea spray aerosol production from leads on both aerosols and the surface snowpack. Therefore, if blowing snow sublimation contributed to the observed sea salt aerosol, the snow being sublimated would have been impacted by sea spray aerosol deposition rather than upward brine migration through the snowpack. Sea spray aerosol production from leads is expected to increase, with thinning and fracturing of sea ice in the rapidly warming Arctic.

The atmospheric multiphase reaction of dinitrogen pentoxide (N2O5) with chloride-containing aerosol particles produces nitryl chloride (ClNO2), which has been observed across the globe. The photolysis of ClNO2 produces chlorine radicals and nitrogen dioxide (NO2), which alter pollutant fates and air quality. However, the effects of local meteorology on near-surface ClNO2 production are not yet well understood, as most observational and modeling studies focus on periods of clear conditions. During a field campaign in Kalamazoo, Michigan, from January–February 2018, N2O5 and ClNO2 were measured using chemical ionization mass spectrometry, with simultaneous measurements of atmospheric particulate matter and meteorological parameters. We examine the impacts of atmospheric turbulence, precipitation (snow, rain) and fog, and ground cover (snow-covered and bare ground) on the abundances of ClNO2 and N2O5. N2O5 mole ratios were lowest during periods of lower turbulence and were not statistically significantly different between snow-covered and bare ground. In contrast, ClNO2 mole ratios were highest, on average, over snow-covered ground, due to saline snowpack ClNO2 production. Both N2O5 and ClNO2 mole ratios were lowest, on average, during rainfall and fog because of scavenging, with N2O5 scavenging by fog droplets likely contributing to observed increased particulate nitrate concentrations. These observations, specifically those during active precipitation and with snow-covered ground, highlight important processes, including N2O5 and ClNO2 wet scavenging, fog nitrate production, and snowpack ClNO2 production, that govern the variability in observed atmospheric chlorine and nitrogen chemistry and are missed when considering only clear conditions.

A gene construct encoding the mature region of Talaromyces minioluteus dextranase (EC 3.2.1.11) fused to the Saccharomyces cerevisiae SUC2 signal sequence was expressed in Pichia pastoris under the constitutive glyceraldehyde 3–phosphate dehydrogenase promoter (pGAP). The increase of the transgene dosage from one to two and four copies enhanced proportionally the extracellular yield of the recombinant enzyme (r-TmDEX) without inhibiting cell growth. The volumetric productivity of the four-copy clone in fed batch fermentation (51 h) using molasses as carbon source was 1706 U/L/h. The secreted N-glycosylated r-TmDEX was optimally active at pH 4.5–5.5 and temperature 50–60 °C. The addition of sucrose (600 g/L) as a stabilizer retained intact the r-TmDEX activity after 1-h incubation at 50–60 °C and pH 5.5. Bacterial dextran in deteriorated sugarcane juice was completely removed by applying a crude preparation of secreted r-TmDEX. The high yield of r-TmDEX in methanol-free cultures and the low cost of the fed batch fermentation make the P. pastoris pGAP-based expression system appropriate for the large scale production of dextranase and its use for dextran removal at sugar mills.

The main objective of this study was to determine the stakeholders (faculty/personnel, students, and clients) perception in the implementation of LSPUs Discipline, Safety and Security Measures. The research method used for this study is descriptive research to gather information regarding the problem. It is specifically designed for the collection of data in order to test the hypotheses and answer the questions concerning the study. The respondents of this study were fifty (50) employees, fifty (50) students, and fifty (50) clients in each of the four campuses of the Laguna State Polytechnic University comprised of six hundred (600) total respondents from Siniloan, Santa Cruz, San Pablo City and Los Baños, campuses. The following statistical tools were used; weighted mean and standard deviation and Pearson Product Moment Correlation. The Pearson’s R was used to test the individual relationship between the Faculty/Personnel, Students, and Clients/Visitors perception on the implementation of Laguna State Polytechnic University’s Discipline, Safety and Security Measures. The study revealed that all indicators of Security Policies and Procedures to wit; Miscellaneous Rules and Regulations, Norms and Decorum, and Disciplinary Measures are all significant, although respondents from Faculty/Personnel, and Students are significantly different to Client. Indicators of Security Risk Management Practices namely: Approach, Responsibilities, and Resources are all significant, although respondents from Faculty/Personnel and Students are significantly different to Client. Indicators of Security Measures namely: Preparedness, Efficiency, and Effectiveness are all significant, although respondents from Faculty/Personnel and Students are significantly different to Client.

Knowing the number of pathogenic microbes in the street foods such as Escherichia coli, coliform, and molds present in street foods around the vicinity of LSPU – SCC was the focused of the study. Determination of the quality of the street foods such as banana cue, kikiam, kwek – kwek, minane, and siomai of which has a high level of safety in the street food around the vicinity of LSPU – SCC were considered. This study utilized the Descriptive research design and the mean in testing and gathering of data. The results reveled that all the street foods tested were safe from E. coli with the mean of ocfu/g and all at lss than 10 cfu/g or 0 count which gathered Satisfactory remarks. However, the findings revealed that the banana cue, minane and siomai were safe from coliform while kwek and kikiam were not with a value of 2800 cfu/g. In addition, all the street foods tested were safe from molds and the total mean of all the microbes present were 987.47 cfu/g which means that the street foods were Unsatisfactory level with 100cfu/g and above count and revealed that only banana cue, minane, and siomai are safe for human consumption while large amount of microbes were found in kikiam, and kwek -kwek which means that they are not safe for human and may cause disease.

Isoprene is the dominant non-methane organic compound emitted to the atmosphere1-3. It drives ozone and aerosol production, modulates atmospheric oxidation and interacts with the global nitrogen cycle4-8. Isoprene emissions are highly uncertain1,9, as is the nonlinear chemistry coupling isoprene and the hydroxyl radical, OH-its primary sink10-13. Here we present global isoprene measurements taken from space using the Cross-track Infrared Sounder. Together with observations of formaldehyde, an isoprene oxidation product, these measurements provide constraints on isoprene emissions and atmospheric oxidation. We find that the isoprene-formaldehyde relationships measured from space are broadly consistent with the current understanding of isoprene-OH chemistry, with no indication of missing OH recycling at low nitrogen oxide concentrations. We analyse these datasets over four global isoprene hotspots in relation to model predictions, and present a quantification of isoprene emissions based directly on satellite measurements of isoprene itself. A major discrepancy emerges over Amazonia, where current underestimates of natural nitrogen oxide emissions bias modelled OH and hence isoprene. Over southern Africa, we find that a prominent isoprene hotspot is missing from bottom-up predictions. A multi-year analysis sheds light on interannual isoprene variability, and suggests the influence of the El Nino/Southern Oscillation.

Inland sources of particulate chloride for atmospheric nitryl chloride (ClNO2) formation remain unknown and unquantified, hindering air quality assessments. Globally each winter, tens of millions of tons of road salt are spread on roadways for deicing. Here, we identify road salt aerosol as the primary chloride aerosol source, accounting for 80–100% of ClNO2 formation, at an inland urban area in the wintertime. This study provides experimental evidence of the connection between road salt and air quality through the production of this important reservoir for nitrogen oxides and chlorine radicals, which significantly impact atmospheric composition and pollutant fates. A numerical model was employed to quantify the contributions of chloride sources to ClNO2 production. The traditional method for simulating ClNO2 considers chloride to be homogeneously distributed across the atmospheric particle population; yet, we show that only a fraction of the particulate surface area contains chloride. Our new single-particle parametrization considers this heterogeneity, dramatically lowering overestimations of ClNO2 levels that have been routinely reported using the prevailing methods. The identification of road salt as a ClNO2 source links this common deicing practice to atmospheric composition and air quality in the urban wintertime environment., Road salt was identified as the primary source of chloride-containing aerosol in the wintertime urban atmosphere. This links deicing practices to air quality via the production of the trace gas ClNO2.

Recent advances in machine learning have enabled image-based prediction of local tissue pathology in gliomas, but the clinical usefulness of these predictions is unknown. We aimed to evaluate the prognostic ability of imaging-based estimates of cellular density for patients with gliomas, with comparison to the gold standard reference of World Health Organization grading.Data from 1181 (207 grade II, 246 grade III, 728 grade IV) previously untreated patients with gliomas from a single institution were analyzed. A pretrained random forest model estimated voxelwise tumor cellularity using MR imaging data. Maximum cellular density was correlated with the World Health Organization grade and actual survival, correcting for covariates of age and performance status.A maximum estimated cellular density of7681 nuclei/mmImage-based estimation of glioma cellularity is a promising biomarker for predicting survival, approaching the prognostic power of World Health Organization grading, with added values of early availability, low risk, and low cost.

The gut microbiome of Mytilus chilensis was analyzed using a next-generation sequencing (NGS) approach using as target the V6-V8 16S rDNA gene regions. The resident gut bacterial communities were analyzed in individuals collected from two locations, both free-living in natural conditions (Wild Type group, WT) and those found in intensive commercial cultures at a Mussel Farm (MF group) off the Chilean coast. A total of 1.2 M of non-chimeric sequences were detected, belonging to 30 phyla, including Fusobacteria, Proteobacteria, Bacteroides, Tenericutes, and 404 genera taxa. The major fraction of the sequences detected corresponded to Vibrionaceae and Fusobacteriaceae families for MF and WT groups, respectively. The gut microbiome of M. chilensis showed a wide diversity of microorganisms; however, differences were observed depending on the origin of samples, where gut samples from the mussel farm showed a lower number of genera when compared to gut tissue samples collected from the wild type individuals. The dominant bacterial are Vibrio, Psychrilyobacter, Mycoplasma, and Psychromonas, that were present with different relative abundancies among the samples analyzed. This next generation sequencing technique, applied for the first time in Chilean mussel (M. chilensis), showed that the gut is a useful tissue for the study of bacterial communities in this bivalve mollusk. The results obtained in this work provided insights into the composition of the microbiota of M. chilensis, unravelling the great bacterial diversity and the effect of habitat on the bacterial community structure.

A new design of a Differential Mobility Analyzer (DMA) was tested with medium aerosol flow rates ranging from 1.5 to 10 slm and high-density particles. The vacuum-tight construction makes it possible to classify pure metal nanoparticles from production processes. The selectable electrical mobility range is comparable to the TSI Long and Nano DMA and covers the full nanometer scale from 15–600 nm. The Medium Flow-DMA (MF-DMA) is characterized by its transfer function, which was determined by a tandem DMA setup using a SMPS with Long DMA downstream. Silver nanoparticles with a density of 10.49 g cm−3 were used to demonstrate the size-selecting performance of high-density particles. The transfer function was calculated for aerosol to sheath gas flow ratios of 1/10, 1/5, and 1/3 directly from the SMPS data by a new method using modeling approach and comparison to the theory. Sufficiently high resolution was reached by increasing the SMPS scan time of the classified size distribution to 300 s. During the investigation, a broadened transfer function could be attributed to an inhomogeneous flow field resulting from the aerosol inlet design. The aerosol inlet of the MF-DMA was optimized by the number of inlet drillings and the opening of the inlet slit to achieve a more homogeneous flow field. CFD simulations of the MF-DMA also confirmed this. The modification improved the transfer function especially for medium aerosol flow rates above 5 slm. Copyright © 2019 American Association for Aerosol Research

As human encroachment increases in the Amazon rain forest, it is important to determine how anthropogenic emissions of reactive gases affect regional atmospheric chemistry. In the present study, we investigate the extent to which urban air plumes modify the levels of ozone (O3) and nitrogen oxides (NOX) in the downwind rain forest. The median mixing ratios of the background O3, NOX, and NOX oxidation products (NOZ) were 20 (15 parts per billion on a volume basis, ppbv), 0.6 ppbv (0.6 ppbv), and 1.0 ppbv (0.5 ppbv) during the dry (wet) season at the study site. Compared to the background environment, air plumes from the city of Manaus had enhanced median mixing ratios for O3 and NOZ by 30–50% and 40–90%, respectively. However, the enhancements of NOX in the air plumes were less than 20%, indicating that the majority of NOX was chemically converted to O3 and NOZ during transport. Results from a photochemical model showed that an injection of 8 ppbv of NOX into the rain forest can cause up to 260% and 150% increases in O3 and hydroxyl radical (OH) levels compared to the background conditions, indicating the likely extent that NOX can modify the air quality and oxidative capacity in the Amazon rain forest. Slopes of the O3-temperature linear relationships increased with NOX levels from 3.7 to 6.5 ppbv per degree Kelvin during the dry season and 1.7–5.5 ppbv per degree Kelvin during the wet season. Average rates of change of the slope with respect to NOZ were approximately 1.8 and 2.3 times higher than those with respect to NOX for the dry and wet seasons. One key conclusion of this study is that NOZ substantially contributed to the O3 formation in response to temperature under enhanced NOX conditions in the forested environment.

In this paper, a design driven comparison between two 190 kVA industrial three-phase two-level voltage source converter (2L-VSC) designs based in silicon carbide (SiC) and silicon (Si) for 690 V grids is presented. These two designs were conceived to have the same nominal power, while switching at reasonable switching speeds and requiring the same case to ambient thermal impedance. Under these conditions, the designs were studied to detect the potential gains and limitations that a pragmatic converter design could feature when using these two technologies regarding cost, efficiency, size and weight. To achieve this, experimentally determined semiconductor characteristics were used to perform simulations, the results of which were then used to design the essential parts of the converter. These designed parts were then corroborated with manufacturers, from which physical characteristics of all designed components were obtained. The results show that the SiC based design presents substantial weight savings and an 11% system cost reduction, while preserving its traditional characteristics such as improved overall efficiency when compared to the silicon based design under the given design requirements and constraints.

The atmospheric multiphase reaction of dinitrogen pentoxide (N2O5) with chloride-containing aerosol particles produces nitryl chloride (ClNO2), which has been observed across the globe. The photolysis of ClNO2 produces chlorine radicals and nitrogen dioxide (NO2), which alter pollutant fates and air quality. However, the effects of local meteorology on near-surface ClNO2 production are not yet well understood, as most observational and modeling studies focus on periods of clear conditions. During a field campaign in Kalamazoo, Michigan from January–February 2018, N2O5 and ClNO2 were measured using chemical ionization mass spectrometry, with simultaneous measurements of atmospheric particulate matter and meteorological parameters. We examine the impacts of atmospheric turbulence, precipitation (snow, rain) and fog, and ground cover (snow-covered and bare ground) on the abundances of ClNO2 and N2O5. N2O5 mole ratios were lowest during periods of lower turbulence and were not statistically significantly different between snow-covered and bare ground. In contrast, ClNO2 mole ratios were highest, on average, over snow-covered ground, due to saline snowpack ClNO2 production. Both N2O5 and ClNO2 mole ratios were lowest, on average, during rainfall and fog because of scavenging, with N2O5 scavenging by fog droplets likely contributing to observed increased particulate nitrate concentrations. These observations, specifically those during active precipitation and with snow-covered ground, highlight important processes, including N2O5 and ClNO2 wet scavenging, fog nitrate production, and snowpack ClNO2 production, that govern the variability in observed atmospheric chlorine and nitrogen chemistry and are missed when considering only clear conditions.

In this paper, a design driven comparison between two 190 kVA industrial three-phase two-level voltage source converter (2L-VSC) designs based in silicon carbide (SiC) and silicon (Si) for 690 V grids is presented. These two designs were conceived to have the same nominal power, while switching at reasonable switching speeds and requiring the same case to ambient thermal impedance. Under these conditions, the designs were studied to detect the potential gains and limitations that a pragmatic converter design could feature when using these two technologies regarding cost, efficiency, size and weight. To achieve this, experimentally determined semiconductor characteristics were used to perform simulations, the results of which were then used to design the essential parts of the converter. These designed parts were then corroborated with manufacturers, from which physical characteristics of all designed components were obtained. The results show that the SiC based design presents substantial weight savings and an 11% system cost reduction, while preserving its traditional characteristics such as improved overall efficiency when compared to the silicon based design under the given design requirements and constraints.

3D computer vision techniques are now required for the virtual reconstruction of ancient buildings and monuments in urban environments. In this paper, we include a new subfield within the broad field of Urban Heritage that we denominate as Rural Heritage (RH), and which is focused on recovering 3D models of small buildings and facilities of significance in rural environments. We, therefore, present a multi-sensory approach whose objective is to create complete architectural documentation of the dovecotes in an extended region of central Spain. This kind of aviary construction was very common in Spanish rural environments during the 19th century and the first half of the 20th century and is representative of an RH building. Sensory fusion was developed using color cameras, 3D terrestrial laser scanners, and photogrammetric techniques with Unmanned Aerial Vehicles (UAV) and achieves precise indoor and outdoor 3D models. The sensory fusion here also refers to the fact that the information coming from different sensors is integrated into a common documentation framework. A total of 80 dovecotes have been referenced and made available to the public in open access resources. The successful results and applicability of our method lead us to believe that the current documentation and the safeguard technologies in the RH field should evolve towards the use of these 3D computer vision techniques.

Frontline service is one of the most essential factors to determine good public governance in any of its offices. An effective and efficient frontline service requires proficient and knowledgeable staff to be assigned as frontlines. For the reason that they face the clients to assist them according to their needs, frontline jobs really an important factor in the delivery of services. As mentioned, frontline services are assigned to address the clients’ needs first hand. They are required to solve clients concern with their utmost skills in services delivery. Frontline also serves as the face of an agency or office. Department of Agrarian Reform (DAR) as one of government entity is created under the Executive Branch of the Philippine Government. It is the lead government agency that upholds and implements comprehensive and genuine agrarian reform which actualizes equitable land distribution, ownership, agricultural productivity, and tenurial security for, of, and with the tillers of the land towards the improvement of their quality of life through the implementation of the Comprehensive Agrarian Reform Program (CARP) through Land Tenure Improvement (LTI), Agrarian Justice and Coordinated delivery of essential Support Services to client beneficiaries (dar.gov.ph). Among the abovementioned programs, these all require a good and impressive frontline service. This study is focused on the assessment of the frontline services of the Department of Agrarian Reform Office – Laguna (DARPO-Laguna). There were three main categories or divisions that have been assessed: 1. Legal Services Division, 2. Land Tenure Services Program (LTSP) Division, and 3. General Frontline Services of DARPO-Laguna. Using the self-constructed questionnaire formulated from the DAR Employee Handbook and Service Performance Model (ServPerf Model), the researcher was able to gather data. These data gathered were tabulated and computed using weighted mean, frequency and percentage, and F-Value and p-value computations. There were three hundred seventy-seven (377) respondents in this study randomly selected from the group of farmers, landowners, Non-Government Organizations, Employees, and Researchers. It reveals from this study that, all the division in DARPO-Laguna that has frontline services including the General Frontline Services was with a great extend when assessed by the respondents. All dimensions and aspects included in this study are acceptable, it means that, in general, DARPO-Laguna Frontline Services is doing a good practice however, still necessitates improvement. In addition, the study found out that there are significant differences in respondents’ assessment when grouped according to their types . Based on the results and findings of the study, it is generally recommended that the management of DARPO-Laguna needs to continue its good practices and may opt to further enhance delivery of services to achieve the best clients’ satisfaction.

The atmospheric boundary layer mediates the exchange of energy, matter, and momentum between the land surface and the free troposphere, integrating a range of physical, chemical, and biological processes and is defined as the lowest layer of the atmosphere (ranging from a few meters to 3 km). In this review, we investigate how continuous, automated observations of the atmospheric boundary layer can enhance the scientific value of co-located eddy covariance measurements of land-atmosphere fluxes of carbon, water, and energy, as are being made at FLUXNET sites worldwide. We highlight four key opportunities to integrate tower-based flux measurements with continuous, long-term atmospheric boundary layer measurements: (1) to interpret surface flux and atmospheric boundary layer exchange dynamics and feedbacks at flux tower sites, (2) to support flux footprint modelling, the interpretation of surface fluxes in heterogeneous and mountainous terrain, and quality control of eddy covariance flux measurements, (3) to support regional-scale modeling and upscaling of surface fluxes to continental scales, and (4) to quantify land-atmosphere coupling and validate its representation in Earth system models. Adding a suite of atmospheric boundary layer measurements to eddy covariance flux tower sites, and supporting the sharing of these data to tower networks, would allow the Earth science community to address new emerging research questions, better interpret ongoing flux tower measurements, and would present novel opportunities for collaborations between FLUXNET scientists and atmospheric and remote sensing scientists.

Knowing the number of pathogenic microbes in the street foods such as Escherichia coli, coliform, and molds present in street foods around the vicinity of LSPU – SCC was the focused of the study. Determination of the quality of the street foods such as banana cue, kikiam, kwek – kwek, minane, and siomai of which has a high level of safety in the street food around the vicinity of LSPU – SCC were considered. This study utilized the Descriptive research design and the mean in testing and gathering of data. The results reveled that all the street foods tested were safe from E. coli with the mean of ocfu/g and all at lss than 10 cfu/g or 0 count which gathered Satisfactory remarks. However, the findings revealed that the banana cue, minane and siomai were safe from coliform while kwek and kikiam were not with a value of 2800 cfu/g. In addition, all the street foods tested were safe from molds and the total mean of all the microbes present were 987.47 cfu/g which means that the street foods were Unsatisfactory level with 100cfu/g and above count and revealed that only banana cue, minane, and siomai are safe for human consumption while large amount of microbes were found in kikiam, and kwek -kwek which means that they are not safe for human and may cause disease. &nbsp

We apply different methods for detection of extreme phenomena (EP) in air-turbulent time series measured in the nocturnal boundary layer above the Amazon forest. The methods used were: (a) a Morlet complex wavelet transform, which is often used in analysis of non-linear application processes. Through the use of the wavelet, it is possible to observe a phase singularity that involves a strong interaction between an extensive range of scales, (b) recurrence plot tests, which were used to identify a sudden change between different stable atmospheric states. (c) statistical analysis of early-warning signals, which verify simultaneous increases in the autocorrelation function and in the variance in the state variable, and (d) analysis of wind speed versus turbulent kinetic energy to identify different turbulent regimes in the stable boundary layer. We found it is adequate to use a threshold to classify the cases of strong turbulence regime, as a result of the occurrence of EP in the tropical atmosphere. All methods used corroborate and indicate synergy between events that culminate in what we classify as EP of the stable boundary layer above the tropical forest.

The explicit coupling at meter and second scales of vegetation's responses to the atmospheric‐boundary layer dynamics drives a dynamic heterogeneity that influences canopy‐top fluxes and cloud formation. Focusing on a representative day during the Amazonian dry season, we investigate the diurnal cycle of energy, moisture and carbon dioxide at the canopy top, and the transition from clear to cloudy conditions. To this end, we compare results from a large‐eddy simulation technique, a high‐resolution global weather model, and a complete observational data set collected during the GoAmazon14/15 campaign. The overall model‐observation comparisons of radiation and canopy‐top fluxes, turbulence, and cloud dynamics are very satisfactory, with all the modeled variables lying within the standard deviation of the monthly aggregated observations. Our analysis indicates that the timing of the change in the daylight carbon exchange, from a sink to a source, remains uncertain and is probably related to the stomata closure caused by the increase in vapor pressure deficit during the afternoon. We demonstrate quantitatively that heat and moisture transport from the subcloud layer into the cloud layer are misrepresented by the global model, yielding low values of specific humidity and thermal instability above the cloud base. Finally, the numerical simulations and observational data are adequate settings for benchmarking more comprehensive studies of plant responses, microphysics, and radiation.

Las emisiones de gases contaminantes a la atmósfera constituyen tanto un problema económico como medioam-biental. En este trabajo se realiza un estudio detallado de las emisiones provocadas por las ramas del sector energético español. Para ello, hemos elaborado para la economía española una Matriz de Contabilidad Social con cuentas ambientales, considerando los seis Gases de Efectos Invernadero que señala el Protocolo de Kioto, y en la que aparece desagregado el sector energético en ocho sectores, incluyendo renovables, con el fin de poder distinguir las emisiones de cada tipo de energía. A partir de esta matriz con cuentas ambientales, se realiza un análisis mediante un modelo multisectorial de tipo lineal, que nos permite obtener las emisiones, tanto directas como indirectas, provoca-das por cada rama del sector energético español. Finalmente se evalúa el impacto que tendría en términos de emisio-nes un cambio en el consumo energético de los hogares a favor de fuentes energéticas renovables. The greenhouse gas emissions to the atmosphere are an economic and environmental problem. In this work we make a detailed study of the emissions from the branches of the Spanish energy sector. To this end, we have developed for the Spanish economy a Social Accounting Matrix (SAM) with Environmental Accounts, considering the six greenhouse gases that the Kyoto Protocol states. In this SAM, the energy sector appears disaggregated in eight sectors, including renewable branches, in order to distinguish the emissions of each type of energy. The analysis is performed using a linear multisector model applied to the SAM, which allows us to obtain the emissions, both direct and indirect, caused by each branch of the Spanish energy sector. Finally, we evaluate the impact in emissions caused by a shift in the household energy consumption towards renewable energy.

Covid-19 pandemic has originated that a great number of countries’ governments demand universities to teach online classes, presenting a challenge to redesign the courses that had construction site visits included in the curricula. The purpose of this work is to present the successful strategies employed on the teaching of building construction, applied in a third-year civil engineering program of the Pontifical Catholic University of Peru. The methodology was designed so that one can adapt the pandemic and post-pandemic stages proposing a balanced use of virtual platforms and software for video conferences and laboratories, incorporating tools like Building Information Modeling, Lean construction, among other systems. Given the sanitary emergency, the construction site visits were replaced by virtual visits to construction projects generated with scanner laser technology, photogrammetry, and BIM, generating digital twins that were stored in online platforms. Students toured the construction project virtually and in an interactive manner, and along with the description of the professionals in charge of the project they were able to reach a good level of comprehension of the organization and the construction processes. In addition, students developed the layout plans of the temporary works with BIM models. On the other hand, the course taught to generate and analyze the unit prices and quantity surveying of activities using the BIM methodology with 5D software, developing the project budget. The success of this methodology is shown through the notable quality of papers and evaluations taken, through the results of surveys taken on students--which had an effectiveness rate of 96.4 % --, and on the improvement opportunities determined. This paper presents tools relevant that may be adapted by the academia and practitioners related to building constructions, for virtual or face-to-face learning.