Integrated ecological modelling for decision support in river management: a lowland river case study (Cauca river in Colombia)

Several practical concepts and software systems have been recently developed in the issue of environmental decision support. However, the application of ecological modelling approaches that integrate hydrodynamic, physical-chemical, and biological components sub-models for predicting macroinvertebrates in rivers, is rather limited and hardly described in literature. The Cauca river is one of most severe cases of contamination for domestic and industrial wastewater discharges in Colombia. One of the most sensitive problems in the Cauca river is the decrease of dissolved oxygen with concentrations near to zero (0) mg/l in some monitoring stations especially during dry season (low flows). Low DO levels affect the ecosystem equilibrium and the functioning and survival of biological communities. In this research an integration of habitat suitability models with the hydrodynamic and physical-chemical water quality model MIKE11 was performed. Ecological models (statistical models) that allow predicting the occurrence and the abundance of macroinvertebrates (Ephemeroptera, Trichoptera and Haplotaxida) in this river under different conditions were built. The integrated ecological model allows to model and to assess the ecological impact of wastewater discharges into the Cauca river and can help to calculate the needed reductions in discharges of organic matter to meet biological quality criteria in this river

Selecting relevant predictors: impact of variable selection on model performance, uncertainty and applicability of models in environmental decision making

One of the crucial steps when developing models is the selection of appropriate variables. In this research we assessed the impact variable selection on the model performance and model applicability. Regression trees were built to understand the relationship between the ecological water quality and the physicalchemical and hydromorphological variables. Different model parameterizations and three combinations of explanatory variables were used for developing the trees. Once constructed, they were integrated with the water quality model (PEGASE) and used to simulate the future ecological water quality. These simulations were summarized per combination of explanatory variables and compared. Three key messages summarize our conclusions. First, it was confirmed that different parameterizations alter the statistical reliability of the trees produced. Secondly, it was found that statistical reliability of the models remained stable when different combinations of explanatory variables were implemented. The determination coefficient (R²) ranged from 0.68 to 0.86; Kappa statistic (K) ranged from 0.15 and 0.46; and the percentage of Correctly Classified Instances (CCI) from 33 to 59%. Thirdly, when applying the models on an independent dataset consisting of future physical-chemical water quality data, different conclusions may be taken, depending on the combination of variables used

Use of habitat suitability modeling in the integrated urban water system modeling of the Drava River (Varazdin, Croatia)

The development of practical tools for providing accurate ecological assessment of rivers and species conditions is necessary to preserve habitats and species, stop degradation and restore water quality. An understanding of the causal mechanisms and processes that affect the ecological water quality and shape macroinvertebrate communities at a local scale has important implications for conservation management and river restoration. This study used the integration of wastewater treatment, river water quality and ecological assessment models to study the effect of upgrading a wastewater treatment plant (WWTP) and their ecological effects for the receiving river. The WWTP and the water quality and quantity of the Drava river in Croatia were modelled in the software WEST. For the ecological modeling, the approach followed was to build habitat suitability and ecological assessment models based on classification trees. This technique allows predicting the biological water quality in terms of the occurrence of macroinvertebrates and the river status according to ecological water quality indices. The ecological models developed were satisfactory, and showed a good predictive performance and good discrimination capacity. Using the integrated ecological model for the Drava river, three scenarios were run and evaluated. The scenario assessment showed that it is necessary an integrated approach for the water management of the Drava river, which considers an upgrading of the WWTP with Nitrogen and Phosphorous removal and the treatment of other diffuse pollution and point sources (including the overflow of the WWTP). Additionally, if an increase in the minimum instream flow after the dams is considered, a higher dilution capacity and a higher self-cleaning capability could be obtained. The results proved that integrated models like the one presented here have an added value for decision support in water management. This kind of integrated approach is useful to get insight in aquatic ecosystems, for assessing investments in sanitation infrastructure of urban wastewater systems considering both, the fulfilling of legal physical chemical emission limits and the ecological state of the receiving waters

From Freight Partnerships to City Logistics Living Labs – Giving Meaning to the Elusive Concept of Living Labs

The paper discusses the growing importance of urban freight research given the increasing urban population trends. The complexity of urban freight systems means that it is essential for the public and private sectors to work together - one way to achieve this has been through freight partnerships. A short review of freight partnerships highlights the way in which they have fostered mutual understanding among urban freight stakeholders. The literature on shared situational awareness (SSA) and joint knowledge production (JKP) has been adapted to position freight partnerships and to further develop and link these partnerships to the concept of a living laboratory concerned with urban freight transport. This novel application of the living lab concept is introduced. Next, the first phases of a city logistics living lab brought in practice in Rotterdam are shortly mentioned. The living lab concept fits the complexities of the urban freight system well and has been a cornerstone of a recently started major freight project in the EU (CITYLAB)

Theoretical Study of Copper Complexes: Molecular Structure, Properties, and Its Application to Solar Cells

We present a theoretical investigation of copper complexes with potential applications as sensitizers for solar cells. The density functional theory (DFT) and time-dependent DFT were utilized, using the M06 hybrid meta-GGA functional with the LANL2DZ (D95V on first row) and DZVP basis sets. This level of calculation was used to find the optimized molecular structure, the absorption spectra, the molecular orbitals energies, and the chemical reactivity parameters that arise from conceptual DFT. Solvent effects have been taken into account by an implicit approach, namely, the polarizable continuum model (PCM), using the nonequilibrium version of the IEF-PCM model

Characterization and analysis of metropolitan freight patterns in Medellin, Colombia

This paper seeks to pilot test a novel way to collect freight and service activity data and analyze the collected data in the metropolitan area of Medellin, Colombia. This research collects data using a multi-layer and multi-actor approach that includes surveys to receivers, suppliers, carriers, and truck drivers. The data are used by the authors to describe the overall freight patterns in the area of study and to show lessons learned. The data collection resulted in 2947 establishments (4.4% of the total establishments in the city), a cordon survey of 2950 commercial vehicles (17% of the total vehicle volume) accessing the urban area, and carrier interviews to ten companies and 130 truck drivers. The results indicate that a total of 33,274 metric tons/day enter the study area, 35,240 tons/day leave the area; while 7000 tons/day are distributed in the study area. In terms of freight trips, 6600 trips/day enter the study zone and 6600 trips/day leave it. The data collection effort enabled the analyses of freight generation patterns. The freight surveys used in the study complement each other, and provided a good depiction of the freight movements in urban areas. It was found that in the Medellin Metropolitan Area, freight-intensive sector establishments generates, on average, significantly more cargo (freight attraction plus production) than the service-intensive sectors. The analyses of the surveys allow the decision makers to understand the nature of the cargo and the generation patterns in different type of establishments. This characterization of the freight patterns is vital for the forecasting of the behavior of the cargo and it is the main input to perform freight demand modeling for city planning, especially for developing countries, where there are too many budget constraints

Deletion of a Pathogenic Mutation-Containing Exon of COL7A1 Allows Clonal Gene Editing Correction of RDEB Patient Epidermal Stem Cells

Recessive dystrophic epidermolysis bullosa is a severe skin fragility disease caused by loss of functional type VII collagen at the dermal-epidermal junction. A frameshift mutation in exon 80 of COL7A1 gene, c.6527insC, is highly prevalent in the Spanish patient population. We have implemented geneediting strategies for COL7A1 frame restoration by NHEJ-induced indels in epidermal stem cells from patients carrying this mutation. TALEN nucleases designed to cut within the COL7A1 exon 80 sequence were delivered to primary patient keratinocyte cultures by non-integrating viral vectors. After genotyping a large collection of vector-transduced patient keratinocyte clones with high proliferative potential, we identified a significant percentage of clones with COL7A1 reading frame recovery and Collagen VII protein expression. Skin equivalents generated with cells from a clone lacking exon 80 entirely were able to regenerate phenotypically normal human skin upon their grafting onto immunodeficient mice. These patientderived human skin grafts showed Collagen VII deposition at the basement membrane zone, formation of anchoring fibrils, and structural integrity when analyzed 12 weeks after grafting. Our data provide a proof-of-principle for recessive dystrophic epidermolysis bullosa treatment through ex vivo gene editing based on removal of pathogenic mutationcontaining, functionally expendable COL7A1 exons in patient epidermal stem cells.The study was mainly supported by DEBRA International—funded by DEBRA Austria (grant termed as Larcher 1). Additional funds come from Spanish grants SAF2013-43475-R and SAF2017-86810-R from the Ministry of Economy and Competitiveness and PI14/00931 and PI17/01747 from the Instituto de Salud Carlos III, all of them co-funded with European Regional Development Funds (ERDF)

Direct impacts of off-hour deliveries on urban freight emissions

The most significant negative environmental impacts of urban trucking result largely from travel in congested traffic. To illustrate the potential of innovative solutions to this problem, this paper presents new research on the emission reductions associated with off-hour freight deliveries (OHD). The paper uses fine-level GPS data of delivery operations during regular-hours (6 AM to 7 PM), and off-hours (7 PM to 6 AM), to quantify emissions in three major cities in the Americas. Using second-by-second emissions modeling, the paper compares emissions under both delivery schedules for: reactive organic gases, total organic gases, carbon monoxide, carbon dioxide, oxides of nitrogen, and particulate matter. The results show that the magnitude of the emission reductions depends on the extent of the change of delivery time. In the case of the “Full” OHD programs of New York City and São Paulo—where the deliveries were made during the late night and early morning periods (7 PM to 6 AM)—the emission reductions are in the range of 45–67%. In the case of the “Partial” OHD used in Bogotá (where OHD took place between 6 PM and 10 PM), the reductions were about 13%. The emission reductions per kilometer are used to estimate the total reductions for the cities studied, and for all metropolitan areas in the world with more than two million residents. The results indicate the considerable potential of OHD as an effective—business friendly—sustainability tool to improve the environmental performance of urban deliveries. The chief implication is that public policy should foster off-hour deliveries, and all forms of Freight Demand Management, where practicable

Comparison between Staphylococcus aureus, strains isolated from medical students in pre-clinical formation and clinical training

OBJECTIVE: To establish the differences between Staphylococcus aureus isolates from medical students in pre-clinical and clinical training and identify the level of susceptibility to methicillin, vancomycin and alternative antibiotics. MATERIALS AND METHODS: A cross-sectional observational design with non-random sampling was used in medical students during pre-clinical and clinical training. Samples were taken from nasal swabs and cultured on blood agar. For beta-hemolytic gram-positive cocci, catalase and coagulase tests were performed and then cultured on mannitol salt agar. Susceptibility to cefoxitin, oxacillin, linezolid, clindamycin and trimethoprim sulfamethoxazole was assessed by using the Kirby-Bauer technique, and for vancomycin, an E-test was performed (Biomerieux®). RESULTS: 51 strains of S. aureus from nasal swabs were isolated from 112 medical students. 68.6% were identifi ed as methicillinsensitive (MSSA) and 31.4% as methicillin-resistant (MRSA). Four MRSA strains showed vancomycin intermediate (VISA 4-8 μg/mL) profile, 41% of MSSA isolates was resistant to clindamycin, 31% to linezolid and 23.5% to trimethoprim sulfamethoxazole. DISCUSSION: MSSA, MRSA and VISA strains are present in nostrils of our medical students, with MRSA showing high resistance levels (>50%) to clindamycin, TMP-SMX and linezolid, and MSSA levels up to 40%. These findings reiterate the need to accomplish good nasal and hands hygiene in order to minimize the spread of S. aureus in community and healthcare facilities