The Effects of 3D Electrical Anisotropy on Magnetotelluric Responses: Synthetic Case Studies

2018 ◽  
Vol 23 (1) ◽  
pp. 61-75
Author(s):  
Wenxin Kong ◽  
Changhong Lin ◽  
Handong Tan ◽  
Miao Peng ◽  
Tuo Tong ◽  
...  
Keyword(s):  
Numerical Modeling ◽  
Finite Difference Method ◽  
Apparent Resistivity ◽  
Electrical Anisotropy ◽  
Staggered Grid ◽  
Qualitative And Quantitative ◽  
Resistivity Tensor ◽  
Quantitative Analyses ◽  
Prism Model ◽  
Euler’S Angles

Using the staggered-grid finite difference method, a numerical modeling algorithm for a 3D arbitrary anisotropic Earth is implemented based on magnetotelluric (MT) theory. After the validation of this algorithm and comparison with predecessors, it was applied to several qualitative and quantitative analyses containing electrical anisotropy and a simple 3D prism model. It was found that anisotropic parameters for ρ 1 , ρ 2 , and ρ 3 play almost the same role in affecting 3D MT responses as in 1D and 2D without considering three Euler's angles α S , α D , and α L . Significant differences appear between the off-diagonal components of the apparent resistivity tensor and also between the diagonal components in their values and distributing features under the influence of 3D anisotropy, which in turn help to identify whether the MT data are generated from 3D anisotropic earth. Considering the deflecting effects arising from the inconsistency between the anisotropy axes and the measuring axes, some strategies are also provided to estimate the deflecting angles associated with anisotropy strike α S or dip α D , which may be used as initial values for the 3D anisotropy inversion. [Figure: see text]

Numerical Modeling of Wave Propagation in Poroelastic Media with a Staggered-Grid Finite-Difference Method

2013 ◽  
Vol 275-277 ◽  
pp. 612-617
Author(s):  
Wen Sheng Zhang ◽  
Li Tong
Keyword(s):  
Numerical Modeling ◽  
Wave Propagation ◽  
Finite Difference ◽  
Finite Difference Method ◽  
Difference Method ◽  
Staggered Grid ◽  
Poroelastic Medium ◽  
Numerical Computations ◽  
Poroelastic Media ◽  
Biot’S Equations

In this paper, wave propagation in poroelastic medium is simulated with a staggered-grid finite-difference method. The formulation is discretized based on the second-order Biot’s equations rather than the corresponding velocity-stress form. In order to eliminate boundary reflections, the PML method is applied. Numerical computations are implemented and the results show the correctness and effectiveness of the schemes presented in this paper.

scholarly journals Performance of 3D Wave Field Modeling Using the Staggered Grid Finite Difference Method with General-Purpose Processors

Energies ◽  
2020 ◽  
Vol 13 (17) ◽  
pp. 4573
Author(s):  
Anna Franczyk ◽  
Damian Gwiżdż ◽  
Andrzej Leśniak
Keyword(s):  
Numerical Modeling ◽  
Finite Difference ◽  
Finite Difference Method ◽  
Wave Field ◽  
Difference Method ◽  
General Purpose ◽  
Staggered Grid ◽  
Computational Time ◽  
Computing Environment ◽  
General Purpose Processors

This paper aims to provide a quantitative understanding of the performance of numerical modeling of a wave field equation using general-purpose processors. In particular, this article presents the most important aspects related to the memory workloads and execution time of the numerical modeling of both acoustic and fully elastic waves in isotropic and anisotropic mediums. The results presented in this article were calculated for the staggered grid finite difference method. Our results show that the more realistic the seismic wave simulations that are performed, the more the demand for memory and the computational capacity of the computing environment increases. The results presented in this article allow the estimation of the memory requirements and computational time of wavefield modeling for the considered model (acoustic, elastic or anisotropic) so that their feasibility can be assessed in a given computing environment and within an acceptable time. Understanding the numerical modeling performance is especially important when graphical processing units (GPU) are utilized to satisfy the intensive calculations of three-dimensional seismic forward modeling.

In situ microprobe quantitation of inorganic particle burden in paraffin sections of lung tissue

1988 ◽  
Vol 46 ◽  
pp. 990-991
Author(s):  
Jerrold L. Abraham
Keyword(s):  
Lung Tissue ◽  
Quantitative Information ◽  
Particulate Material ◽  
Paraffin Sections ◽  
Tissue Samples ◽  
Qualitative And Quantitative ◽  
The Past ◽  
Quantitative Analyses ◽  
Data Result

Inorganic particulate material of diverse types is present in the ambient and occupational environment, and exposure to such materials is a well recognized cause of some lung disease. To investigate the interaction of inhaled inorganic particulates with the lung it is necessary to obtain quantitative information on the particulate burden of lung tissue in a wide variety of situations. The vast majority of diagnostic and experimental tissue samples (biopsies and autopsies) are fixed with formaldehyde solutions, dehydrated with organic solvents and embedded in paraffin wax. Over the past 16 years, I have attempted to obtain maximal analytical use of such tissue with minimal preparative steps. Unique diagnostic and research data result from both qualitative and quantitative analyses of sections. Most of the data has been related to inhaled inorganic particulates in lungs, but the basic methods are applicable to any tissues. The preparations are primarily designed for SEM use, but they are stable for storage and transport to other laboratories and several other instruments (e.g., for SIMS techniques).

Qualitative and quantitative analyses of some Plantago species from Serbia and Montenegro

Planta Medica ◽  
2008 ◽  
Vol 74 (09) ◽  
Author(s):  
T Jankovic ◽  
G Zdunic ◽  
K Savikin ◽  
I Beara ◽  
N Mimica-Dukić
Keyword(s):  
Serbia And Montenegro ◽  
Qualitative And Quantitative ◽  
Quantitative Analyses

scholarly journals Assessment of Photo-Induced Cytotoxic Activity of Cachrys sicula and Cachrys libanotis Enriched-Coumarin Extracts against Human Melanoma Cells

Plants ◽  
2021 ◽  
Vol 10 (1) ◽  
pp. 123
Author(s):  
Mariangela Marrelli ◽  
Maria Rosaria Perri ◽  
Valentina Amodeo ◽  
Francesca Giordano ◽  
Giancarlo A. Statti ◽  
...  
Keyword(s):  
Phenolic Content ◽  
Melanoma Cells ◽  
Therapeutic Approaches ◽  
Qualitative And Quantitative ◽  
Aerial Parts ◽  
Naturally Occurring ◽  
Quantitative Analyses ◽  
Solid Liquid ◽  
Uva Radiation

Photochemotherapy is one of the most interesting current therapeutic approaches for the treatment of melanoma. Different classes of naturally occurring phytochemicals demonstrated interesting photoactive properties. The aim of this study was to evaluate the photocytotoxic potential of two Cachrys species from Southern Italy: C. sicula and C. libanotis (Apiaceae). The enriched-coumarin extracts were obtained from aerial parts through both traditional maceration and pressurized cyclic solid-liquid (PCSL) extraction using Naviglio extractor®. Qualitative and quantitative analyses of furanocoumarins were performed with GC-MS. The photocytotoxic effects were verified on C32 melanoma cells irradiated at a dose of 1.08 J/cm2. The apoptotic responses were also assessed. Moreover, phenolic content and the in vitro antioxidant potential were estimated. Xanthotoxin, bergapten, and isopimpinellin were identified. All the samples induced concentration-dependent photocytotoxic effects (IC50 ranging from 3.16 to 18.18 μg/mL). The C. libanotis sample obtained with Naviglio extractor® was the most effective one (IC50 = 3.16 ± 0.21 μg/mL), followed by C. sicula sample obtained with the same technique (IC50 = 8.83 ± 0.20 μg/mL). Both Cachrys samples obtained through PCSL induced up-regulation of apoptotic signals such as BAX (Bcl2-associated X protein) and PARP (poly ADP-ribose polymerase) cleavage. Moreover, these samples proved to be more photoactive, giving a greater upregulation of p21 protein in the presence of UVA radiation. Obtained results suggest that investigated species could be promising candidates for further investigations aimed to find new potential drugs for the photochemotherapy of skin cancer.

scholarly journals A framework for identifying and learning from countries that demonstrated exemplary performance in improving health outcomes and systems

2020 ◽  
Vol 5 (12) ◽  
pp. e002938
Author(s):  
Austin Carter ◽  
Nadia Akseer ◽  
Kevin Ho ◽  
Oliver Rothschild ◽  
Niranjan Bose ◽  
...  
Keyword(s):  
Mixed Methods ◽  
Global Health ◽  
Health Outcomes ◽  
Mixed Methods Research ◽  
Multidisciplinary Teams ◽  
Ongoing Research ◽  
Qualitative And Quantitative ◽  
Success Stories ◽  
Quantitative Analyses ◽  
Comprehensive Framework

This paper introduces a framework for conducting and disseminating mixed methods research on positive outlier countries that successfully improved their health outcomes and systems. We provide guidance on identifying exemplar countries, assembling multidisciplinary teams, collecting and synthesising pre-existing evidence, undertaking qualitative and quantitative analyses, and preparing dissemination products for various target audiences. Through a range of ongoing research studies, we illustrate application of each step of the framework while highlighting key considerations and lessons learnt. We hope uptake of this comprehensive framework by diverse stakeholders will increase the availability and utilisation of rigorous and comparable insights from global health success stories.

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