scholarly journals CoastalME version 1.0: a Coastal Modelling Environment for simulating decadal to centennial morphological changes

Author(s):  
Andrés Payo ◽  
David Favis-Mortlock ◽  
Mark Dickson ◽  
Jim W. Hall ◽  
Martin Hurst ◽  
...  

Abstract. Modelling coastal morphological changes at decadal to centennial time scales is required to support sustainable coastal management world-wide. One approach involves coupling of landform-specific components (e.g. cliff, beach, dunes, estuaries, etc.) that have been independently developed. An alternative, and novel approach explored in this paper is to capture the essential characteristics of the landform-specific models using a common spatial representation within an appropriate software-environment. In the proposed Coastal Modelling Environment (CoastalME), change in coastal morphology is formulated by means of dynamically linked raster and geometrical objects. A grid of raster cells provides the data structure for representing quasi-3D spatial heterogeneity and sediment conservation. Other geometrical objects (lines, areas and volumes) that are consistent with, and derived from, the raster structure represent a library of coastal elements (e.g. shoreline, beach profiles and estuary volumes) as required by different landform-specific models. As a proof-of-concept, we illustrate the potential capabilities of CoastalME by integrating a cliff-beach model. We verify that CoastalME can reproduce behaviours of each individual landform-specific model. Their integration within the framework of CoastalME reveals behaviours that emerge from landforms interaction and which have not previously been captured, such as the influence of the regional bathymetry on the local alongshore sediment transport gradient. This is the first step of the framework development, which provides an alternative to directly coupling existing models.

2017 ◽  
Vol 10 (7) ◽  
pp. 2715-2740 ◽  
Author(s):  
Andrés Payo ◽  
David Favis-Mortlock ◽  
Mark Dickson ◽  
Jim W. Hall ◽  
Martin D. Hurst ◽  
...  

Abstract. The ability to model morphological changes on complex, multi-landform coasts over decadal to centennial timescales is essential for sustainable coastal management worldwide. One approach involves coupling of landform-specific simulation models (e.g. cliffs, beaches, dunes and estuaries) that have been independently developed. An alternative, novel approach explored in this paper is to capture the essential characteristics of the landform-specific models using a common spatial representation within an appropriate software framework. This avoid the problems that result from the model-coupling approach due to between-model differences in the conceptualizations of geometries, volumes and locations of sediment. In the proposed framework, the Coastal Modelling Environment (CoastalME), change in coastal morphology is represented by means of dynamically linked raster and geometrical objects. A grid of raster cells provides the data structure for representing quasi-3-D spatial heterogeneity and sediment conservation. Other geometrical objects (lines, areas and volumes) that are consistent with, and derived from, the raster structure represent a library of coastal elements (e.g. shoreline, beach profiles and estuary volumes) as required by different landform-specific models. As a proof-of-concept, we illustrate the capabilities of an initial version of CoastalME by integrating a cliff–beach model and two wave propagation approaches. We verify that CoastalME can reproduce behaviours of the component landform-specific models. Additionally, the integration of these component models within the CoastalME framework reveals behaviours that emerge from the interaction of landforms, which have not previously been captured, such as the influence of the regional bathymetry on the local alongshore sediment-transport gradient and the effect on coastal change on an undefended coastal segment and on sediment bypassing of coastal structures.


2017 ◽  
Vol 72 (5) ◽  
pp. 254-259 ◽  
Author(s):  
I. Burlacov ◽  
S. Hamann ◽  
H.-J. Spies ◽  
A. Dalke ◽  
J. Röpcke ◽  
...  

2021 ◽  
Vol 9 (7) ◽  
pp. 1463
Author(s):  
Tamirat Tefera Temesgen ◽  
Kristoffer Relling Tysnes ◽  
Lucy Jane Robertson

Cryptosporidium oocysts are known for being very robust, and their prolonged survival in the environment has resulted in outbreaks of cryptosporidiosis associated with the consumption of contaminated water or food. Although inactivation methods used for drinking water treatment, such as UV irradiation, can inactivate Cryptosporidium oocysts, they are not necessarily suitable for use with other environmental matrices, such as food. In order to identify alternative ways to inactivate Cryptosporidium oocysts, improved methods for viability assessment are needed. Here we describe a proof of concept for a novel approach for determining how effective inactivation treatments are at killing pathogens, such as the parasite Cryptosporidium. RNA sequencing was used to identify potential up-regulated target genes induced by oxidative stress, and a reverse transcription quantitative PCR (RT-qPCR) protocol was developed to assess their up-regulation following exposure to different induction treatments. Accordingly, RT-qPCR protocols targeting thioredoxin and Cryptosporidium oocyst wall protein 7 (COWP7) genes were evaluated on mixtures of viable and inactivated oocysts, and on oocysts subjected to various potential inactivation treatments such as freezing and chlorination. The results from the present proof-of-concept experiments indicate that this could be a useful tool in efforts towards assessing potential technologies for inactivating Cryptosporidium in different environmental matrices. Furthermore, this approach could also be used for similar investigations with other pathogens.


2021 ◽  
Vol 17 ◽  
Author(s):  
Swayamprakash Patel ◽  
Ashish Patel ◽  
Mruduka Patel ◽  
Umang Shah ◽  
Mehul Patel ◽  
...  

Background: Probe sonication and High-speed homogenizer are comparatively costly equipment to fabricate the nanoparticles. Many academic and research institutions cannot afford the procurement and maintenance of such sophisticated equipment. In the present work, a newer idea is conceptualized, which can be adopted by the underprivileged research institutions to fabricate solid lipid nanoparticles (SLN) in the absence of sophisticated equipment. The current work describes the pilot-level trials of this novel approach. This study represents the preliminary proof-of-concept trials for which the Indian patent application (3508/MUM/2015) is filed. Method: A frugal piece of equipment was made using a 50 ml centrifuge tube with conical bottom and a piezoelectric mist maker or humidifier. SLNs were prepared by combining the quasi-emulsion solvent evaporation approach and ultrasonic vibration approach. A quasi-emulsion was composed by the dropwise mixing of the organic solvent containing drug & lipid with an aqueous solution containing surfactant under continuous ultrasonic vibration in the piezoelectric chamber. The size of the droplets was significantly reduced due to piezoelectric ultrasonic vibration. Under the provision of mild vacuum and heat generated by vibration, the organic solvent was evaporated, which leaves behind a suspension of SLN. In the present work, albendazole was selected as a model drug. Various trials with Compritol 888 ATO® and Precirol ATO 5® as a lipid carrier and Tween 80 and Poloxamer 188 as a surfactant were performed. Zeta potential of SLNs was improved by the addition of polyelectrolytes like K2SO4 and Na4P2O7. Result and Conclusion: The ratio of drug to lipid was optimized to 1:4 for the most favorable results. SLN with a minimum Z-average diameter of 98.59 nm, -21 mV zeta potential, and 34.064 % (SD 10.78, n=9) entrapment efficiency were developed using the Precirol ATO 5 ® as a lipid carrier. The proof of concept for this novel approach is established through the development of Albendazole SLNs. This approach must also be evaluated for the development of polymeric nanoparticles and vesicular formulations. The further sophistication of the frugal equipment may allow more control over the quality of SLN. This approach will enable underprivileged researchers to prepare Nanopharmaceuticals. Researchers and students of such institutions can focus on the application of SLN by resolving the constraint of sophisticated equipment with this novel approach. This novel approach should also be tried for polymeric and vesicular nanopharmaceuticals.


2011 ◽  
Vol 63 (1) ◽  
pp. 171-177
Author(s):  
G. T. Parker

As water quality models and their implementation have become increasingly diverse, complex and proprietary, a need for more thorough understanding of the differences between each alternative arises. The work presented here proposes a novel visualization paradigm for water quality applications which can be used to understand difference between implementations of identical and different conceptual models. A proof-of-concept visualization tool was developed and tested again three scenarios for four different conceptual models of biochemical kinetics. Results show representative figures illustrating how the approach can communicate differences in model complexity and dynamic behaviour. The proposed tool should help ensure more suitable application of water quality models in varied contexts. A discussion of quantifying model complexity in a single metric is also presented, and recommendations are made on the selection of various representational forms for communicating and exploring specific model characteristics.


Author(s):  
Santosh Tiwari ◽  
Joshua Summers ◽  
Georges Fadel

A novel approach using a genetic algorithm is presented for extracting globally satisfycing (Pareto optimal) solutions from a morphological chart where the evaluation and combination of “means to sub-functions” is modeled as a combinatorial multi-objective optimization problem. A fast and robust genetic algorithm is developed to solve the resulting optimization problem. Customized crossover and mutation operators specifically tailored to solve the combinatorial optimization problem are discussed. A proof-of-concept simulation on a practical design problem is presented. The described genetic algorithm incorporates features to prevent redundant evaluation of identical solutions and a method for handling of the compatibility matrix (feasible/infeasible combinations) and addressing desirable/undesirable combinations. The proposed approach is limited by its reliance on the quantifiable metrics for evaluating the objectives and the existence of a mathematical representation of the combined solutions. The optimization framework is designed to be a scalable and flexible procedure which can be easily modified to accommodate a wide variety of design methods that are based on the morphological chart.


2020 ◽  
Vol 6 (21) ◽  
pp. eaba5996 ◽  
Author(s):  
Yue Qiao ◽  
Fei Yang ◽  
Tingting Xie ◽  
Zhen Du ◽  
Danni Zhong ◽  
...  

Microalgae, a naturally present unicellular microorganism, can undergo light photosynthesis and have been used in biofuels, nutrition, etc. Here, we report that engineered live microalgae can be delivered to hypoxic tumor regions to increase local oxygen levels and resensitize resistant cancer cells to both radio- and phototherapies. We demonstrate that the hypoxic environment in tumors is markedly improved by in situ–generated oxygen through microalgae-mediated photosynthesis, resulting in notably radiotherapeutic efficacy. Furthermore, the chlorophyll from microalgae produces reactive oxygen species during laser irradiation, further augmenting the photosensitizing effect and enhancing tumor cell apoptosis. Thus, the sequential combination of oxygen-generating algae system with radio- and phototherapies has the potential to create an innovative treatment strategy to improve the outcome of cancer management. Together, our findings demonstrate a novel approach that leverages the products of photosynthesis for treatment of tumors and provide proof-of-concept evidence for future development of algae-enhanced radio- and photodynamic therapy.


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