scholarly journals Assessment of Input Parameters and Calibration Methods for Simulating Prairie Pothole Hydrology using AnnAGNPS

2021 ◽  
Vol 37 (3) ◽  
pp. 495-503
Author(s):  
Brady A Nahkala ◽  
Amy L Kaleita ◽  
Michelle L Soupir

HighlightsModel equifinality incurs user-driven decisions when modeling with AnnAGNPS.Prairie pothole models should be calibrated using a limited parameter search space.LiDAR-derived surface areas best represent prairie pothole hydrology in AnnAGNPS.Modeling field-scale prairie pothole spill-and-fill dynamics is currently limited.Abstract. The Annualized Agricultural Non-Point Source (AnnAGNPS) model was used to predict water volume in individual prairie potholes within the Des Moines Lobe of Iowa. AnnAGNPS can represent prairie potholes as static wetland areas located on preferential flow paths at field scale, whereas standard practice of watershed modeling is to fill depressions while preparing input data, and whereas models have lumped parameters at scales too large for individual pothole representation, or are considered too complex for widespread implementation. Here, we assess how key user inputs affect hydrologic calibration of 6 AnnAGNPS prairie pothole models, suggest methods for calibrating and modeling the impact of some potholes at field scale, and explain challenges in modeling prairie potholes with AnnAGNPS. Results indicate that user-defined pothole surface area does not significantly affect statistical calibration of the model. Nash-Sutcliffe Efficiency 0.26 to 0.79, R2 ranged from 0.37 to 0.80 and RSR ranged from 0.46 to 0.86. The area that best simulates pothole hydrology and expected physical parameters is derived from LiDAR and is considered the maximum extent of the pothole. Potholes were calibrated using a stepwise, iterative, limited search space method using multiple representations of their inundation extent. We graphically assessed statistical parameters to identify calibrated models and chose input parameters within reasonable ranges of published literature. This helped formulate our recommendation for the modeled pothole area. Finally, AnnAGNPS is limited in its ability to simulate field-scale pothole networks due to the placement of potholes within the model’s subbasin network. Investigating high-resolution subbasin delineation or more specific wetland placement may alleviate this issue. Keywords: AnnAGNPS, Farmed wetlands, Hydrology, Prairie potholes, Prairie pothole region.

Author(s):  
Sayyid Arrasyid ◽  
Zahidah Hasan ◽  
Izza Mahdiana Apriliani ◽  
Heti Herawati

Cirata Reservoir is one of the three cascade reservoirs fed by the Citarum Watershed with an area of ​​62 km2 (6.200 ha) and has a water volume of 1.900 million m3. The great potential of the waters in the Cirata Reservoir is utilized by the local community as a source of livelihood, namely by conducting aquaculture activities using floating net cages (FNC) in excess. FNC is thought to be a source of waste that reduces reservoir water quality. This research aims to determine the impact of FNC cultivation on primary productivity with different FNC densities at each station. The research was conducted in Cianjur Regency by taking on three stations, namely in the areas of Jangari, Maleber, and Patok Beusi on November 6 - December 8, 2019. The method used in the research was purposive sampling then analyzed in detail and quantitatively. The results show that reservoir waters have an average of physical parameters, namely temperature 32.2-32.6oC, transparency 0.59-0.68 meters, pH 7.1-7.3, carbon dioxide 15.4-16.1 mg / l, Dissolved Oxygen 6.9-7.3 mg / l, Biochemical Oxygen Demand 6.1-7.8 mg / l, nitrate 0.208-0.222 mg / l, ammonia 0.002833-0.003056 mg / l, phosphate 0,165-0,167 mg / l and primary productivity 240,36-277,90 mgC/m3/hour. This shows that the water indicator is still classified as good because it does not exceed the water quality standard.


1976 ◽  
Vol 72 ◽  
pp. 29-46
Author(s):  
G. Cayrel de Strobel

A few examples are given showing the utility of the catalogue of iron/hydrogen determinations for astrophysical researches. These are: (a)Histograms of dwarfs and giants analyzed in detail with spectral type between O and M.(b)Logarithmic abundances diagrams of given stars.(c)The impact on spectral classification of high-dispersion-detailed-analysis results.(d)The use of well-determined chemical and physical parameters of nearby stars for the construction of HR diagrams in the (Mbol –log Teff) plane.The spectra of F, G and K stars having the iron lines at their best visibility, special emphasis has been given to the results concerning these stars.


Author(s):  
Lindsey Gilman ◽  
Amanda Bess ◽  
Brian Drollette ◽  
Don Danmeier ◽  
Karen Murray

Oil spill risk assessments (OSRAs) do not currently distinguish between potentially more toxic, fresh crude oil and less toxic, highly-weathered residues which limits the understanding of the highest risk areas to prioritize mitigation measures and allocate response resources. Fate and trajectory models, used commonly for OSRA, have advanced significantly over the last five years now with enhanced ability to model chemical and physical parameters at greater resolution. Using this enhanced resolution, modelers may be able to provide some indication of the weathered state of the oil as input to the OSRA. In order to evaluate the degree of certainty in such a prediction, it is necessary to better understand the uncertainty in the modeled weathering processes that influence the toxicity of the oil. Emulsification plays a significant role in modeling of oil thickness (and therefore photo-modification), evaporation, and dissolution which are important modulators of oil toxicity. In this project, the emulsification algorithms of three currently available fate and trajectory models, ADIOS, OILMAP/SIMAP, and OSCAR, were evaluated to gain a better understanding of the degree of certainty in the modeled weathered state of oil. In this work, the basis of emulsification algorithms implemented in the models referenced above were identified, and it was found that each of these models incorporates emulsification differently. ADIOS2 relies on emulsification data gathered from mixing oil and water in a food processor. An updated version of ADIOS2 (ADIOS3) is based on a new formulation that is dependent on measured SARA components of the oil, but is still under construction and is not yet implemented. OILMAP/SIMAP use the algorithm presented in Mackay and Zagorski (1982). OSCAR uses a water uptake algorithm that was calibrated to in-house laboratory experiments. Further investigation into the development of each of these emulsification algorithms provided insight into the degree of uncertainty in these models and their input parameters, and what oil types may not be appropriately characterized by the implemented emulsification model. Additionally, the impact of that uncertainty on oil fate was investigated by evaluating the changes in the amount of emulsification when modifying user input parameters within realistic assumption ranges. The findings and comparison of the implementation of these emulsification algorithms and the sensitivity of the results to different inputs is presented here.


Minerals ◽  
2021 ◽  
Vol 11 (7) ◽  
pp. 779
Author(s):  
Mohamed Gomah ◽  
Guichen Li ◽  
Salah Bader ◽  
Mohamed Elkarmoty ◽  
Mohamed Ismael

The awareness of the impact of high temperatures on rock properties is essential to the design of deep geotechnical applications. The purpose of this research is to assess the influence of heating and cooling treatments on the physical and mechanical properties of Egyptian granodiorite as a degrading factor. The samples were heated to various temperatures (200, 400, 600, and 800 °C) and then cooled at different rates, either slowly cooled in the oven and air or quickly cooled in water. The porosity, water absorption, P-wave velocity, tensile strength, failure mode, and associated microstructural alterations due to thermal effect have been studied. The study revealed that the granodiorite has a slight drop in tensile strength, up to 400 °C, for slow cooling routes and that most of the physical attributes are comparable to natural rock. Despite this, granodiorite thermal deterioration is substantially higher for quick cooling than for slow cooling. Between 400:600 °C is ‘the transitional stage’, where the physical and mechanical characteristics degraded exponentially for all cooling pathways. Independent of the cooling method, the granodiorite showed a ductile failure mode associated with reduced peak tensile strengths. Additionally, the microstructure altered from predominantly intergranular cracking to more trans-granular cracking at 600 °C. The integrity of the granodiorite structure was compromised at 800 °C, the physical parameters deteriorated, and the rock tensile strength was negligible. In this research, the temperatures of 400, 600, and 800 °C were remarked to be typical of three divergent phases of granodiorite mechanical and physical properties evolution. Furthermore, 400 °C could be considered as the threshold limit for Egyptian granodiorite physical and mechanical properties for typical thermal underground applications.


Author(s):  
Gary Sutlieff ◽  
Lucy Berthoud ◽  
Mark Stinchcombe

Abstract CBRN (Chemical, Biological, Radiological, and Nuclear) threats are becoming more prevalent, as more entities gain access to modern weapons and industrial technologies and chemicals. This has produced a need for improvements to modelling, detection, and monitoring of these events. While there are currently no dedicated satellites for CBRN purposes, there are a wide range of possibilities for satellite data to contribute to this field, from atmospheric composition and chemical detection to cloud cover, land mapping, and surface property measurements. This study looks at currently available satellite data, including meteorological data such as wind and cloud profiles, surface properties like temperature and humidity, chemical detection, and sounding. Results of this survey revealed several gaps in the available data, particularly concerning biological and radiological detection. The results also suggest that publicly available satellite data largely does not meet the requirements of spatial resolution, coverage, and latency that CBRN detection requires, outside of providing terrain use and building height data for constructing models. Lastly, the study evaluates upcoming instruments, platforms, and satellite technologies to gauge the impact these developments will have in the near future. Improvements in spatial and temporal resolution as well as latency are already becoming possible, and new instruments will fill in the gaps in detection by imaging a wider range of chemicals and other agents and by collecting new data types. This study shows that with developments coming within the next decade, satellites should begin to provide valuable augmentations to CBRN event detection and monitoring. Article Highlights There is a wide range of existing satellite data in fields that are of interest to CBRN detection and monitoring. The data is mostly of insufficient quality (resolution or latency) for the demanding requirements of CBRN modelling for incident control. Future technologies and platforms will improve resolution and latency, making satellite data more viable in the CBRN management field


2021 ◽  
Author(s):  
Stephen C. L. Watson ◽  
Adrian C. Newton ◽  
Lucy E. Ridding ◽  
Paul M. Evans ◽  
Steven Brand ◽  
...  

Abstract Context Agricultural intensification is being widely pursued as a policy option to improve food security and human development. Yet, there is a need to understand the impact of agricultural intensification on the provision of multiple ecosystem services, and to evaluate the possible occurrence of tipping points. Objectives To quantify and assess the long-term spatial dynamics of ecosystem service (ES) provision in a landscape undergoing agricultural intensification at four time points 1930, 1950, 1980 and 2015. Determine if thresholds or tipping points in ES provision may have occurred and if there are any detectable impacts on economic development and employment. Methods We used the InVEST suite of software models together with a time series of historical land cover maps and an Input–Output model to evaluate these dynamics over an 85-year period in the county of Dorset, southern England. Results Results indicated that trends in ES were often non-linear, highlighting the potential for abrupt changes in ES provision to occur in response to slight changes in underlying drivers. Despite the fluctuations in provision of different ES, overall economic activity increased almost linearly during the study interval, in line with the increase in agricultural productivity. Conclusions Such non-linear thresholds in ES will need to be avoided in the future by approaches aiming to deliver sustainable agricultural intensification. A number of positive feedback mechanisms are identified that suggest these thresholds could be considered as tipping points. However, further research into these feedbacks is required to fully determine the occurrence of tipping points in agricultural systems.


2020 ◽  
Vol 8 (Suppl 3) ◽  
pp. A141-A141
Author(s):  
Yumi Ohtani ◽  
Kayleigh Ross ◽  
Aditya Dandekar ◽  
Rashid Gabbasov ◽  
Michael Klichinsky

BackgroundWe have previously developed CAR-M as a novel cell therapy approach for the treatment of solid tumors.1 CAR-M have the potential to overcome key challenges that cell therapies face in the solid tumor setting – tumor infiltration, immunosuppression, lymphocyte exclusion – and can induce epitope spreading to overcome target antigen heterogeneity. While macrophages transduced with the adenoviral vector Ad5f35 (Ad CAR-M) traffic to tumors, provide robust anti-tumor activity, and recruit and activate T cells, we sought to identify a robust non-viral method of macrophage engineering in order to reduce the cost of goods, manufacturing complexity, and potential immunogenicity associated with viral vectors.MethodsAs innate immune cells, macrophages detect exogenous nucleic acids and respond with inflammatory and apoptotic programs. Thus, we sought to identify a means of mRNA delivery that avoids recognition by innate immune sensors. We screened a broad panel of mRNA encoding an anti-HER2 CAR comprising multiplexed 5’Cap and base modifications using an optimized and scalable electroporation approach and evaluated the impact of interferon-β priming on CAR-M phenotype and function.ResultsWe identified the optimal multiplexed mRNA modifications that led to maximal macrophage viability, transfection efficiency, intensity of CAR expression, and duration of expression. Non-viral HER2 CAR-M phagocytosed and killed human HER2+ tumor cells. Unlike Ad CAR-M, mRNA CAR-M were not skewed toward an M1 state by mRNA electroporation. Priming non-viral CAR-M with IFN-β induced a durable M1 phenotype, as shown by stable upregulation of numerous M1 markers and pathways. IFN-β priming significantly enhanced the anti-tumor activity of CAR but not control macrophages. IFN-β primed mRNA CAR-M were resistant to M2 conversion, maintaining an M1 phenotype despite challenge with various immunosuppressive factors, and converted bystander M2 macrophages toward M1. Interestingly, priming mRNA CAR-M with IFN-β significantly enhanced the persistence of CAR expression, overcoming the known issue of rapid mRNA turnover. RNA-seq analysis revealed that IFN-β priming affected pathways involved in increasing translation and decreasing RNA degradation in human macrophages.ConclusionsWe have established a novel, optimized non-viral CAR-M platform based on chemically modified mRNA and IFN-β priming. IFN-β priming induced a durable M1 phenotype, improved CAR expression, improved CAR persistence, led to enhanced anti-tumor function, and rendered resistance to immunosuppressive factors. This novel platform is amenable to scale-up, GMP manufacturing, and represents an advance in the development of CAR-M.ReferenceKlichinsky M, Ruella M, Shestova O, et al. Human chimeric antigen receptor macrophages for cancer immunotherapy. Nat Biotechnol 2020;38(8):947–953.


Catalysts ◽  
2021 ◽  
Vol 11 (6) ◽  
pp. 675
Author(s):  
Hugo Savill Russell ◽  
Louise Bøge Frederickson ◽  
Ole Hertel ◽  
Thomas Ellermann ◽  
Steen Solvang Jensen

NOx is a pervasive pollutant in urban environments. This review assesses the current state of the art of photocatalytic oxidation materials, designed for the abatement of nitrogen oxides (NOx) in the urban environment, and typically, but not exclusively based on titanium dioxide (TiO2). Field trials with existing commercial materials, such as paints, asphalt and concrete, in a range of environments including street canyons, car parks, tunnels, highways and open streets, are considered in-depth. Lab studies containing the most recent developments in the photocatalytic materials are also summarised, as well as studies investigating the impact of physical parameters on their efficiency. It is concluded that this technology may be useful as a part of the measures used to lower urban air pollution levels, yielding ∼2% NOx removal in the immediate area around the surface, for optimised TiO2, in some cases, but is not capable of the reported high NOx removal efficiencies >20% in outdoor urban environments, and can in some cases lower air quality by releasing hazardous by-products. However, research into new material is ongoing. The reason for the mixed results in the studies reviewed, and massive range of removal efficiencies reported (from negligible and up to >80%) is mainly the large range of testing practices used. Before deployment in individual environments site-specific testing should be performed, and new standards for lab and field testing should be developed. The longevity of the materials and their potential for producing hazardous by-products should also be considered.


2021 ◽  
Vol 3 (8) ◽  
Author(s):  
Ting Liu ◽  
Gabriel Lodewijks

Abstract Abstract On the basis of the influence of dry season on ship traffic flow, the gathering and dissipating process of ship traffic flow was researched with Greenshields linear flow—density relationship model, the intrinsic relationship between the ship traffic congestion state and traffic wave in the unclosed restricted channel segment was emphatically explored when the ship traffic flow in a tributary channel inflows, and the influence law of multiple traffic waves on the ship traffic flow characteristics in unclosed restricted segment is revealed. On this basis, the expressions of traffic wave speed and direction, dissipation time of queued ships and the number of ships affected were provided, and combined with Monte Carlo method, the ship traffic flow simulation model in the restricted channel segment was built. The simulation results show that in closed restricted channel segment the dissipation time of ships queued is mainly related to the ship traffic flow rate of segments A and C, and the total number of ships affected to the ship traffic flow rate of segment A. And in unclosed restricted channel segment, the dissipation time and the total number of ships affected are also determined by the meeting time of the traffic waves in addition to the ship traffic flow rate of segments. The research results can provide the theoretical support for further studying the ship traffic flow in unclosed restricted channel segment with multiple tributaries Article Highlights The inflow of tributaries' ship traffic flows has an obvious impact on the traffic conditions in the unenclosed restricted channel segment. The interaction and influence between multiple ship traffic waves and the mechanism of generating new traffic waves are explained. The expression of both dissipation time of queued ships and the total number of ships affected in the closed and unclosed restricted channel segment are given.


Author(s):  
Sofia Ainonen ◽  
Mysore V Tejesvi ◽  
Md. Rayhan Mahmud ◽  
Niko Paalanne ◽  
Tytti Pokka ◽  
...  

Abstract Background Intrapartum antibiotic prophylaxis (IAP) is widely used, but the evidence of the long-term effects on the gut microbiota and subsequent health of children is limited. Here, we compared the impacts of perinatal antibiotic exposure and later courses of antibiotic courses on gut microbiota. Methods This was a prospective, controlled cohort study among 100 vaginally delivered infants with different perinatal antibiotic exposures: control (27), IAP (27), postnatal antibiotics (24), and IAP and postnatal antibiotics (22). At 1 year of age, we performed next-generation sequencing of the bacterial 16S ribosomal RNA gene of fecal samples. Results Exposure to the perinatal antibiotics had a clear impact on the gut microbiota. The abundance of the Bacteroidetes phylum was significantly higher in the control group, whereas the relative abundance of Escherichia coli was significantly lower in the control group. The impact of the perinatal antibiotics on the gut microbiota composition was greater than exposure to later courses of antibiotics (28% of participants). Conclusions Perinatal antibiotic exposure had a marked impact on the gut microbiota at the age of 1 year. The timing of the antibiotic exposure appears to be the critical factor for the changes observed in the gut microbiota. Impact Infants are commonly exposed to IAP and postnatal antibiotics, and later to courses of antibiotics during the first year of life. Perinatal antibiotics have been associated with an altered gut microbiota during the first months of life, whereas the evidence regarding the long-term impact is more limited. Perinatal antibiotic exposure had a marked impact on the infant’s gut microbiota at 1 year of age. Impact of the perinatal antibiotics on the gut microbiota composition was greater than that of the later courses of antibiotics at the age of 1 year.


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